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01 - ASSESSMENT OF WATER MIGRATION IN MULTI-COMPONENT SNACKS BY MAGNETIC RESONANCE IMAGING
02 - STRUCTURAL CHARACTERIZATION OF THE POLYSACCHARIDE PRODUCED BY LACTOBACILLUS HELVETICUS CNRZ32 BY HIGH-RESOLUTION NMR SPECTROSCOPY: EVIDENCE OF A PHOSPHOETHANOLAMINE SUBSTITUENT
 
03 - NMR INVESTIGATIONS OF INDUSTRIAL DOUGH PROCESSING AND STORAGE BY NMR
 
04 - LOW-FIELD NMR T2 RELAXOMETRY APPLIED TO MONITOR PHASE TRANSITIONS DURING COOLING OF CREAM
 
05 - CHANGES IN CHEMICAL-PHYSICAL PROPERTIES OF MYOFIBRILLAR PROTEINS AND MYOWATER DURING COOKING OF MEAT- COMBINED LOW-FIELD NMR RELAXAOMETRY AND FT-IR SPECTROSCOPY
 
06 - IMPROVEMENT OF SPECTRAL RESOLUTION BY CO-ADDITION OF ALIGNED SPECTRA FROM SELECTED VOXELS OF THE SAMPLE
07 - T1-T2 CORRELATION SPECTROSCOPY OF COMPLEX FOOD
 
08 - SEPARATION AND IDENTIFICATION OF EXTRACTS OF TOMATO JUICE PULP BY 1H NMR
 
09 - USING LOW RESOLUTION NMR FOR THE DETERMINATION OF TOTAL LIPID CONTENT IN VARIOUS TYPES OF ANIMAL FEED
 
10 - 1H HR-MAS NMR AND CHEMOMETRIC ANALYSIS TO STUDY COMMERCIAL PHYTOTERAPIC PLANTS
 
11 - CORRELATION OF POROUS AND FUNCTIONAL PROPERTIES OF FOOD MATERIALS BY NMR RELAXOMETRY AND MULTIVARIATE ANALYSIS
 
12 - USE OF SNIF-NMR IN VINEGAR ANALYSIS
 
13 - GM SOYBEAN CROPS RECOGNIZE BY 1H HR-MAS NMR AND CHEMOMETRIC ANALYSIS
 
14 - LOSS OF MOISTURE FROM HARVESTED RICE SEEDS ON MRI
 
15 - 77SE NMR USING A 1 MM PROBE - A NEW HOPE
 
16 - QUALITY CONTROL OF BEER USING HIGH-RESOLUTION NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY AND MULTIVARIATE ANALYSIS
 
17 - ESR and NMR Spectroscopy Studies on Emulsions Containing β-Lactoglobulin and Oxidised Methyl Linoleate
 
18 - NUTRITIONAL COMPONENTS IN COD (GADUS MORHUA) MUSCLE AND CHANGES DUE TO FREEZING AND THAWING EXAMINED BY HR 1H MR SPECTROSCOPY
 
19 - SIMULTANEOUS MAPPING OF STRUCTURAL- AND TEMPERATURE-CHANGES DURING HEATING OF FOOD IN WATER BY MRI
20 - WHEAT FLOUR ENZYMATIC AMYLOLYSIS MONITORED BY IN SITU 1H-NMR SPECTROSCOPY
 
21 - IDENTIFICATION OF PHENOLIC COMPOUNDS IN OLIVE OIL BY LIQUID CHROMATOGRAPHY WITH NUCLEAR MAGNETIC RESONANCE (LC NMR)
 
22 - APPLICATION OF FTIR AND NMR SPECTROSCOPY FOR THE DETERMINATION OF ORIGIN AND DATE OF PRODUCTION OF BEER
 
23 - STUDIES OF FISH FREEZING USING MR IMAGING
 
24 - BLENDS ANALYSIS OF ARABICA AND ROBUSTA RAW COFFEES SPECIES THROUGH 1H NMR AND CHEMOMETRIC METHODS
 
25 - SODIUM AND FAT DISTRIBUTION IN SMOKED SALMON IN RELATION WITH WATER DYNAMICS ACCESSED BY 1H AND 23Na MRI
26 - INVESTIGATION OF MARINE BIVALVES MORPHOLOGY BY IN VIVO MRI. FIRST ANATOMICAL RESULTS OF A PROMISING TECHNIQUE
27 - COMPARATIVE STUDIES OF FOOD POLYMER HYDRATION BEHAVIOR
 
28 - NUCLEAR MAGNETIC RESONANCE IMAGING (MRI) – DETECTION OF INTERIOR DEFECTS IN PROCESSED PORK
 
29 - HIGH RESOLUTION IMAGING OF FAT DISTRIBUTION IN MEAT USING 3D-PGSE
30 - THE USE SOLUTION NMR TO THE STUDY OF COUMA UTILIS – SORVA FRUIT
 
31 - USE OF HR-MAS AND X-RAY TO STUDY THE GELATINIZATION PROCESS OF FRUIT SEED STARCHES
 
32 - MULTIVARIATE CHEMOMETRIC ANALYSIS OF MAGNETIC RESONANCE IMAGES IN RELATION TO FOOD QUALITY
33 - METABONOMICS STRATEGY FOR THE DETECTION OF THE EFFECTS OF THE CHAMOMILE (MATRICARIS RECUTITA L) IN TAKES
 
34 - COOKING EFFECTS ON WATER DISTRIBUTION AND MOBILITY IN POTATOES USING NMR RELAXATION
 
35 - NON-DESTRUCTIVE DETECTION OF INTERNAL BRUISE AND SPRAING DISEASE SYMPTOMS IN POTATOES USING MAGNETIC RESONANCE IMAGING (MRI)
 
36 - APPLICATIONS OF OLFACTOMETRY IN FOOD SCIENCE
37 - THE EFFECTS OF EMULSION FORMATION ON NMR SPECTRA
(PDF)
38-40 - STUDY OF THE BEHAVIOR OF AMINO ACIDS IN AQUEOUS SOLUTIONS BY TIME DOMAIN-NMR AND HIGH RESOLUTION NMR (3 POSTERS)

41 - CHANGES IN PROTON AND CARBON-13 NMR OF WHEAT AND SOY BREADS DURING STORAGE

 

42 - ON THE USE OF LOW FIELD NMR METHODS FOR THE DETERMINATION OF TOTAL LIPID CONTENT IN MARINE PRODUCTS

 

43 - MRI and NMR spectroscopy study of post-harvest maturing coconut

 

44 - BALASAMIC VINEGAR AND AGE MARKERS: 1H NMR STUDIES

 

45 - 1H HR–MAS NMR FOR DETECTION OF FISH MEAL ADULTERATION

 

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01 - ASSESSMENT OF WATER MIGRATION IN MULTI-COMPONENT SNACKS BY MAGNETIC RESONANCE IMAGING

Pedro Ramos Cabrer, John P. M. van Duynhoven*, Hans Timmer, Gerard van Dalen, Klaas Nicolay
Utrecht University, Unilever R&D Vlaardingen, Eindhoven University of Technology

Consumer appreciation of snacks is often provided by contrast in texture between different components of the product. For almost all of the known multi-component snacks, this implies contrast in water abundance and activity. Without proper precautions, this inevitably leads to water migration and loss in texture (quality) during shelf life of the product. Hence, a major challenge in the development of snacks with ambient stable texture contrast is to find strategies to control water migration. When the efficacy of such strategies could be assessed in a non-invasive manner this could aid significantly in the development of novel snack products.
Therefore we have developed two MRI protocols that can assess water transport phenomena in multi-component systems in a non-invasive manner. Both protocols can be used for systems of realistic dimensions (7 cm), but differ in their emphasis on molecular mobility information and temporal resolution.
The first protocol, emphasizing molecular mobility information (at the cost of temporal resolution) was successfully applied to a snack consisting of a bread roll filled with cheese and sausages. The slow migration of water in this system (weeks) could be monitored at three molecular mobility levels, i.e. glassy/crystalline, semi-solid and liquid like. In order to span the width of molecular mobility regimes, recourse was taken to a combined use of Single Point Imaging and ‘conventional’ Spin Echo MRI techniques.
A second protocol, tailored to monitoring relatively rapid (hours/days) water transport phenomena, was used to study stability of a sandwich snack, consisting of bread filled with components with high water activity (tomato, ham and cheese). In order to monitor components with low molecular mobility (i.e. bread), a Single Point Imaging MRI approach was used.
Both protocols were successfully applied for non-invasive assessment of the efficacy of experimental ‘water migration control’ technologies, such as edible barriers. These results were used to enable ‘snack engineering’ in a rational manner.

  

 
02 - STRUCTURAL CHARACTERIZATION OF THE POLYSACCHARIDE PRODUCED BY LACTOBACILLUS HELVETICUS CNRZ32 BY HIGH-RESOLUTION NMR SPECTROSCOPY: EVIDENCE OF A PHOSPHOETHANOLAMINE SUBSTITUENT

Marie–Rose Van Calsteren 1, Danièle Atlan 2 and Christophe Gilbert 2
1 Centre de recherche et de développement sur les aliments, Agriculture et Agroalimentaire Canada, Saint–Hyacinthe, Québec, Canada
2 Unité de Microbiologie et Génétique, UMR 5122, CNRS, Université de Lyon 1, Villeurbanne, France

Strain CNRZ32 of Lactobacillus helveticus was grown in milk or chemically defined medium, and its exocellular polysaccharide was isolated from the supernatant or the whole culture and purified by TCA and acetone precipitations, solvent extractions, dialysis, and lyophilization. Purity was checked by gel permeation chromatography. Structural characterization was performed by chemical methods and with 1H, 13C, and 31P NMR spectroscopy. Essentially identical spectra were obtained under all culture and purification conditions.
Sugar analysis by TLC or GC revealed the presence of rhamnose, galactose, glucose, and an amino sugar. C, H, N, and P were found by elemental analysis.
13C NMR spectra displayed 46 signals, seven of which were in the anomeric region, three could be attributed to rhamnose methyls, two to an acetyl substituent, one to C2 of an acetamido sugar, and two were found to belong to phosphoethanolamine. Of the four methylene belonging to C6 of hexoses, two were nonsubstituted, one was glycosylated, and one was substituted with phosphoethanolamine.
On the 1H NMR spectra, seven signals were present in the anomeric region, the methyl region contained signals for three rhamnose and one acetyl, and two signals could be attributed to phosphoethanolamine. Two rhamnose and one galactose had the α anomeric configuration, whereas the third rhamnose, the second galactose, one glucose, and one acetamido sugar were β linked. NOESY, ROESY and HMBC spectra gave linkage information.
The data were consistent with a multibranched heptasaccharide repeating unit. Phosphoethanolamine has never been reported to occur in a polysaccharide produced by lactic acid bacteria.
 
03 - NMR INVESTIGATIONS OF INDUSTRIAL DOUGH PROCESSING AND STORAGE BY NMR

John van Duynhoven, Eddy Esselink, Peter Weegels
Unilever R&D Vlaardingen, The Netherlands

It is well recognised that the quality of industrial bakery products strongly depends on dough processing and supply chain conditions. The industrial conditions can differ significantly from the artisanal manufacturing process. Industrial dough processing typically involves large-scale kneaders, extruders and moulders. Furthermore, in contrast to the artisanal process, the industrial supply chain of bakery products often involves the storage and transport of frozen dough to bakers. In order to enable a rational design of industrial dough processing and storage conditions, a good understanding of the involved microstructural phenomena is required. Many microstructural and rheological studies on dough have already been reported. However, most of them pertain to laboratory scale processing and storage experiments, using either rheology, microscopy or spectroscopy. In our studies we have deployed NMR in conjunction with rheology and microscopy, in order to study the microstructural phenomena as they occur during processing at industrial manufacturing lines. The same techniques were also used to study the microstructural effects as they occur during frozen storage of dough.

In the microstructural assessment of an industrial dough processing line [1] the impact of industrial kneading, extrusion and moulding was monitored by NMR relaxometry, rheology and electron microscopy. Also the effect of proofing and resting steps was studied. These processing steps had a considerable impact on the structure and cohesiveness of the gluten/starch/water components of the dough. NMR relaxometry showed how a molecular biopolymer (gluten) network was being formed, disrupted and restored during the different stages of industrial manufacturing. These NMR observations were well in line with results from electron microscopy and rheology.
During frozen storage of dough, NMR relaxometry [2] indicated that water is released from the gluten network. This is in agreement with Infrared spectroscopy, which shows conformational changes in the gluten proteins. In line with these observations, electron microscopy showed that the released water migrated to the gas cells in the dough, where ice crystals were formed. At the macroscopic scale, MRI measurements indicate that these ice crystals are not evenly distributed over the dough.

[1] Esselink, E, van Aalst, H, Maliepaard, M, Henderson, T, Hoekstra, N, van Duynhoven, JPM, Impact of dough processing on structure: a rheology, NMR and EM approach, Cereal Chem 80(4): 419-423 (2003)

[2] Esselink, E, van Aalst, H, Maliepaard, M, van Duynhoven, JPM, Long term storage effect in frozen dough by spectroscopy and microscopy, Cereal Chem 80(4): 396-403 (2003)
 
04 - LOW-FIELD NMR T2 RELAXOMETRY APPLIED TO MONITOR PHASE TRANSITIONS DURING COOLING OF CREAM

Hanne Christine Bertram, Lars Wiking, Jacob Holm Nielsen, Henrik J. Andersen
Department of Food Science, Danish Institute of Agricultural Sciences, Research Centre Foulum

Milk fat crystallizes during cooling. The crystallization temperature depends on the content of saturated and unsaturated fatty acids in the milk (1-2). Milk fat is very susceptible to compositional changes, and the fatty acid composition of milk is directly affected by the diet of the cow. Knowledge of crystallization temperature of milk fat would enable development of superior cooling strategies in storage and pumping of raw milk before pasteurisation to preserve superior quality of the milk for further use. Low-field 1H NMR has shown potential as a future at-/on-line method in several foods.

Low-field 1H NMR transverse relaxation (T2) was measured during cooling (31C to 4C) of cream with low and high content of palmitate (C16) induced by different feeding strategies (3). Distributed analysis of the T2 relaxation data revealed marked differences in the T2 relaxation characteristics of the liquid fat population (10-100 ms), which could be ascribed to differences in the size of the fat globules in the two types of cream. Principal component analysis (PCA) on the obtained T2 relaxation decays showed clear shifts in NMR relaxation behaviour at 17˚C and 22C in cream with a low and high content of palmitate, respectively. DSC measurements on the creams revealed that these shifts are taking place at the onset of crystallization of fat. Consequently, the present study demonstrates that potential of low-field 1H NMR can to measure phase transitions in a medium-fat containing matrix as cream.

1. Shi et al. (2001). Journal of Dairy Science, 84, 2392-2401.
2. Steffensen et al. (2004). Milchwissenschaft, 59, 176-179.
3. Wiking et al. (2003). International Dairy Journal, 13, 799-803.
 
05 - CHANGES IN CHEMICAL-PHYSICAL PROPERTIES OF MYOFIBRILLAR PROTEINS AND MYOWATER DURING COOKING OF MEAT- COMBINED LOW-FIELD NMR RELAXAOMETRY AND FT-IR SPECTROSCOPY

Hanne Christine Bertram 1), Achim Kohler 2), Henrik J. Andersen 1), Ragni Ofstad 2)
1) Department of Food Science, Danish Institute of Agricultural Sciences, Research Centre Foulum, 2) MATFORSK, Norwegian Food Research Institute

Meat quality is affected by multiple and mutual interacting factors from gene to fork. Especially, fresh meat characteristics and the cooking process are substantial for the sensory perception of meat. Consequently, a basic understanding of physical-chemical properties in fresh meat and during cooking is important to elucidate and optimise perceived meat quality. In the present study low-field NMR T2 relaxation measurements were combined with FT-IR spectroscopy during cooking of pork in order to investigate the changes in water characteristics, protein structures, and the relationship between the progressions in these two features in two meat qualities (normal and high ultimate pH).

Measurements were performed during cooking from 28˚C to 81˚C. Pronounced changes in both T2 relaxation data and FT-IR spectroscopic data were observed during cooking, revealing severe changes in the water properties and structural organization of proteins. Upon distributed analysis of the T2 relaxation data the changes during cooking were displayed as broader populations with faster relaxation times corresponding to water being confined within smaller more heterogeneous structures upon cooking. The FT-IR data revealed increases in α-sheet and decreases in β-helix structures of the myofibrillar proteins upon cooking. Distributed NMR T2 relaxation data and FT-IR spectra were compared by partial least square regression. This revealed correlation between the FT-IR peaks reflecting α-sheet and β-helix structures and the NMR relaxation population reflecting myofibrillar water and also expelled ‘bulk’ water (T2 relaxation times >500 ms). Accordingly, the present study demonstrates that structural changes in proteins during cooking of meat are associated with simultaneous alterations in the chemical-physical properties of the water within the meat.
 
06 - IMPROVEMENT OF SPECTRAL RESOLUTION BY CO-ADDITION OF ALIGNED SPECTRA FROM SELECTED VOXELS OF THE SAMPLE

Ana Sepe, Igor Serša
Jozef Stefan Institute, Ljubljana, Slovenia

A spectrum from a sample has often limited resolution because of poor magnetic filed inhomogeneity within the sample. This can improved by magnet shimming when variations of magnetic field within the sample are moderate. In many samples the magnetic field is highly inhomogeneous due to large internal magnetic field gradients that have origin in susceptibility effects within the sample. If that is the case, magnet shimming can usually not help to improve magnetic field homogeneity. This situation is typical also in NMR of food samples when we want to acquire a spectrum from a part of the sample in an undestructive way. Standard spectroscopic methods that are based on nonselective excitation or cubic localization produce poor results because a spectrum is acquired from a large part of the sample where magnetic field is unhomogeneous. Spectroscopic imaging (SI) methods allow acquisition of spectra from much smaller parts (voxels) of the sample with much better magnetic field homogeneity and the spectra have therefore better resolution. However, the signal to noise ratio (SNR) may be low. To regain the SNR of the standard spectroscopic methods and to preserve spectral resolution of the SI method we propose co-addition of SI spectra with their prior alignment. Spectral alignment is needed because spectra from an uniform part of the sample look identical except they are differently shifted because of the magnetic field variations between different voxels. Our preliminary measurements indicate that by this method spectral resolution may be improved by a factor up to 3.

  

 
07 - T1-T2 CORRELATION SPECTROSCOPY OF COMPLEX FOOD

N Marigheto, S Benamira, S Duarte, A Costa, K Wright, B Hills,
Institute of Food Research, Norwich Research Park, Colney, Norwich, UK

The potential use of NMR two-dimensional T1-T2 correlation spectroscopy [1-3] is explored for two different aspects of food science, namely processing effects on raw food materials and quality changes on storage. The inversion recovery sequence is inserted immediately in front of a CPMG sequence and by systematically varying the recovery time t1 we arrive at the two-dimensional T1-T2 pulse sequence. The two independent variables are the recovery time, t1 and the CPMG acquisition time, t2. The t1 period is dominated by longitudinal relaxation, whereas t2 is dominated by transverse relaxation processes. The T1-T2 cross-correlation spectrum of raw and cooked egg white and yolk showed peaks corresponding to the pools of exchangeable and non-exchanging protons. Peaks corresponding to the non-exchanging CH protons of the more rigid gel network formed by the denaturation of major protein components are seen in the spectrum of cooked egg white and yolk [4]. T1-T2 correlation spectroscopy is also shown to be a powerful tool for monitoring the effect of high pressure and microwave processing on the microscopic water distribution and starch chain dynamics in potato and waxy maize starch [5]. The potential for distinguishing storage disorders in fruit such as mealiness in apples is explored. Avocado maturity can also be monitored from the increase in oil content determined from the relative water and oil peak areas [6].

References:

1. Song, Y.-Q., Venkataramanan, L., Hurlimann, M.D., Flaum, M., Frulla, P., and Straley, C., J. Magn. Reson. 154:261-268, 2002.
2. Hurlimann, M.D., and Venkataramanan, L., J. Magn. Reson. 157:31-42, 2002.
3. Godefroy, S., Creamer, L.K., Watkinson, P.J., and Callaghan, P.T., The use of 2D Laplace Inversion in Food Material, page 85 in Magnetic Resonance in Food Science, Ed Belton, P. S., Gil, A. M., Webb, G.A. and Rutledge, D., The Royal Society of Chemistry, Cambridge, 2002.
4. Hills, B., Benamira, S., Marigheto, N. and Wright, K., T1-T2 Correlation Analysis of Complex Food, Applied Magnetic Resonance (in press)
5. Hills, B., Costa A., Marigheto, N., and Wright,K., T1-T2 Correlation Studies of High Pressure Processed Starch and Potato Tissue, Applied Magnetic Resonance (submitted)
6. Hills, B., Duarte S. and Marigheto, N., An NMR Relaxation Study of Avocado Quality, Magnetic Resonance Imaging (submitted)
 
08 - SEPARATION AND IDENTIFICATION OF EXTRACTS OF TOMATO JUICE PULP BY 1H NMR

Stefano Tiziani, Yael Vodovotz
Food Science & Technology Department, The Ohio State University, Columbus, USA

Epidemiological studies have shown the health benefits of tomato consumption for the preventionof chronic diseases. Antioxidants, such as lycopene and β-carotene, are the health promoting compounds in tomato products. In this study, different tomato pulp fractions were analyzed by 1H NMR using a Bruker DRX-600 spectrometer. The hydrophilic components of tomato pulp were extracted with D2O and analyzed by COSY, TOCSY, HSQC and HMBC 2D sequences. The combination of these techniques enabled to distinguish and identify several sugars, organic acids and amino acids. Hydrophobic compounds, once extracted by 1:1 acetone/hexane and dried by flushing nitrogen, were dissolved in CDCl3 and analyzed by COSY, TOCSY, and HSQC 2D spectroscopy. Diffusion ordered 2D NMR spectroscopy (DOSY) helped to identify different carotenoid isomers. This work confirms that NMR spectroscopy is a powerful noninvasive technique that allows a characterization not only of sugars, proteins and organic acids but also the identifications of minor compounds such as carotenoids.
 
09 - USING LOW RESOLUTION NMR FOR THE DETERMINATION OF TOTAL LIPID CONTENT IN VARIOUS TYPES OF ANIMAL FEED

Geir Humborstad Sørland, Frank Lundby, Chrisitan Jepsen, Anita Rosen
Anvendt Teknologi A/S, Matforsk, DLG-Centrallaboratorium, Felleskjøpet, Norway

An optimized Carr Purcell Meiboom Gill (CPMG) pulse sequence has been applied for determining the total lipid content in various types of animal feed. It has been found that even with low resolution equipment it is not only possible to quantify the total amount of lipids present in the sample, but also discriminate between two classes of lipids in samples where the moisture has been dried out; lipids with short T2 (~ 0.2 ms) and lipids with long T2 (~100 ms). The NMR results are compared against chemical extraction methods.

Keywords: Quantification, lipid, phospholipid, animal feed, low field NMR
 
10 - 1H HR-MAS NMR AND CHEMOMETRIC ANALYSIS TO STUDY COMMERCIAL PHYTOTERAPIC PLANTS

Cristina Daolio 1, Antonio Gilberto Ferreira 1, Marcia M.C. Ferreira 2,
1 DQ/UFSCAR-São Paulo-Brazil 2 IQ/UNICAMP-São Paulo-Brazil

Catuaba is a commercial phytoterapic product and has a long history of using in Brazilian popular medicine as physical and mental tonic and especially as a sexual stimulant. However, there is a big confusion regarding to the correct species sold commercially as Catuaba. One species is Anemopaegma arvense (Bignoniaceae) called the “official Catuaba” wich principal active compounds are the alkaloids. Nevertheless, recent studies showed that in the herbal commerce today the species Trichilia catigua (Meliaceae) is the most consumed species and the limonoids are the chemical markers for this family.
In this work we analyse samples with official botanical classification of both species and eight commercial samples by using 1H HR/MAS and liquid 1H NMR. The spectra data showed that after PCA analysis the samples sold in commercial market are not from Anemopaegma arvense like we will spect. We can also saw that most of them are very close with Trichilia catigua and few one are completely different from this two species. In this case, probably it will be a mixture of differents plants species. The spectral analysis indicated that both methods, líquid and HR/MAS, lead to the same results. In 1H HR/MAS NMR technique we used the crude bark tree without any pretreatment and for liquid experiments a crude methanol extract.
The 1H NMR data were acquire in BRUKER 9.4 Tesla equipment and all measurements were done in triplicate using a 4 mm rotor and 5 mm inverse detection probe, respectively and we use the PCA for chemometric analysis.
 
11 - CORRELATION OF POROUS AND FUNCTIONAL PROPERTIES OF FOOD MATERIALS BY NMR RELAXOMETRY AND MULTIVARIATE ANALYSIS

Adrian Haiduc, A.A. Reska, John van Duynhoven
Unilever R&D Vlaardingen, The Netherlands

The porous properties of food materials are known to determine important macroscopic parameters such as water-holding capacity and texture. The measurement of these macroscopic and functional parameters stands as a considerable challenge. In conventional approaches, understanding is built from a long process of establishing macrostructure-property relations in a rational manner. Only recently, multivariate approaches were introduced for the same purpose.
We tested this approach for model systems consisting of oil in water emulsion gels stabilised by protein, form complex structures built from fat droplets, protein aggregates, dispersed water droplets, all of which have an influence on the final product properties. NMR time domain decay curves were recorded for emulsions with varied levels of fat, protein and water. Hardness, dry matter content and water drainage were determined by other means and analysed for correlation with the NMR data with multi variate techniques. Partial Least Squares (PLS) can calibrate and predict these properties directly from the continuous NMR exponential decays. Orthogonal Signal Correction filters from the overlapping signals the uncorrelated information and yields regression coefficients higher than 95%. The PLS coefficients themselves belong to the continuous exponential domain and explain the connection between NMR data and emulsion properties after multiexponential fitting. Transformation of the NMR decays into a discreet domain with non-negative least squares permits the use of multi linear regression (MLR) on the resulting amplitudes as predictors and hardness or water drainage as responses.
 
12 - USE OF SNIF-NMR IN VINEGAR ANALYSIS

Elisangela Fabiana Boffo 1, Antonio Gilberto Ferreira 2
1 UNIVERSIDADE FEDERAL DE SÃO CARLOS, 2 UNIVERSIDADE FEDERAL DE SÃO CARLOS, BRAZIL

In Brazil one of the most use of vinegar is in the industrial foods but we also use with a bactericidal propose. In this case we do not need to care wich is the sugar source to start the fermentation process but the final product change dramatically if it is from sugar cane or grapes for instance.
This work describe the use of SNIF-NMR techniques to classified vinegar comercial samples using the 1H/2H isotopic relation by NMR. All the eighteen comercial sample were obtained from the local shopping and submited a liquid/liquid extraction using 80/150 (v.v. vinegar/diethyl ether) during 24 hours. The 1H/2H NMR spectra were recorded in a BRUKER 9.4 Tesla equipment without fluorine lock and all measurements were done in triplicate in a 5 mm probe at 298K.The internal reference was TMS for 1H NMR spectra and TMU for stablish the isotopic relationship.
The results show that it is possible to predict unequivocally the isotopic 1H/2D relationship in the comercial vinegar samples wich were originated from plants that they use the C3 and C4 but not clearlly from CAM biossinthetic metabolism. The 1H/2D relationship founded are: C3 (99 –112 ppm), C4 (aprox. 130 ppm) and CAM (aprox. 106 ppm). We can also distinguish acetic acid from C3 (grapes) and C4 (sugar cane) when they are mixture togheter in a agrins comercial sample. The isotopic relationship for others vinegars originated from: apple (C3), rice (C3), orange juice (C3), pineaple (CAM), honey (C3) and sinthetic acetic acid were also found.
 
13 - GM SOYBEAN CROPS RECOGNIZE BY 1H HR-MAS NMR AND CHEMOMETRIC ANALYSIS

Andersson Barison 1, Glaucia Braz Alcantara 2, Antonio Gilberto Ferreira 2, José Franciso Feraz de Toledo 3, Marcia Miguel Castro Ferreira 4
1 Universidade Estadual de Mato Grosso do Sul – UEMS, 2 Universidade Federal de São Carlos – UFSCar, 3 Empresa Brasileira de Pesquisa Agropecuária – Embrapa, 4 Universidade Estadual de Campinas - UNICAMP

In the last few years genetically modified (GM) crops, mainly herbicide tolerant soybean, had a rapidly acceptance by producers in several places in the world. Because genetic modification in food crops is a relatively new technology we must to concern about its environmental and human beings impact. Moreover, the use of GM crops in many countries, mainly in European Union, must follow regulations and it is very important to have tools for this.
In this work we show a new methodology to recognize GM soybean crops by 1H HR-MAS NMR and chemometric analysis. For this propose we use two samples of GM and one of “conventional” soybean varieties with identical origin and cultivated at the same conditions. The 1H HR-MAS NMR spectra, and the PCA allowed to distinguish the GM samples from their traditional specimens with a good results. This data also were used to built a classify model which was able to classify some unknown samples. This results show us that NMR could be a very attractive analytical technique because its permits to obtain a fast spectra with resolution enough to distinguish samples with small differences without sample pretreatment. Moreover, 1H NMR interpretation of observed differences in the spectra of GM and no GM crops could give important informations about the compounds involved in this discrimination.
The 1H NMR data were acquired in BRUKER 9.4 Tesla equipment and all measurements were done in triplicate using a 4 mm rotor at 298K and we use the PCA for chemometric analysis.
 
14 - LOSS OF MOISTURE FROM HARVESTED RICE SEEDS ON MRI

Nobuaki Ishida, Shigehiro Naito
National Food Research Institute, Japan

The drying process of harvested rice seeds greatly affects the rice grain quality. In rice seeds, water content is already very low at harvest, just over 20 %. Therefore, it has been difficult to trace water distribution in a seed by ordinary MRI measurement. The recently developed SPI (single point mapping imaging) method can detect water in a seed with low water content. In this study, the decrease of water in rice seeds after harvesting at various drying temperatures was traced by the SPI method, and the decrease of image intensity, which is proportional to removable water content, was compared with the results of the oven method.
Most of the water was present in the embryo and endosperm. The water reduction rate was larger on the outside than in the central position of the rice seeds at 50oC, although this discrepancy was not obvious at 40oC. Water reduction was brought about with time according to the kinetics of the multiple components, for both MR imaging and the ventilated-oven method. Images were continuously measured (10 min per image for 100 min). The reduction rate of water from rice kernels increased rapidly with temperature near 60oC then rose slowly above 60oC. Latent heat was calculated as 15 kcal/mol•deg from the changes of drying rate at temperatures below 60oC.
 
15 - 77SE NMR USING A 1 MM PROBE - A NEW HOPE

Claus Cornett a, Bente Gammelgård a, Till Kühn b
a Danish University of Pharmaceutical Sciences, Department of Analytical chemistry
b Bruker Biospin, Fällenden, Switzerland

A selenium metabolite previously isolated from rat urine is for the first time shown to be found in human urine also. The metabolite was "purified" from 15 L human urine yielding what corresponds to about 10 mg of selenium and idenfied using ICPMS, LC-MS and 1H-, 13C-, and 77Se NMR using a 1 mm microprobe.
 
16 - QUALITY CONTROL OF BEER USING HIGH-RESOLUTION NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY AND MULTIVARIATE ANALYSIS

Dirk W. Lachenmeier, Willi Frank, Eberhard Humpfer, Manfred Spraul
Chemisches und Veterinäruntersuchungsamt (CVUA) Karlsruhe, Chemisches und Veterinäruntersuchungsamt (CVUA) Karlsruhe, Bruker BioSpin GmbH, NMR Division, Rheinstetten, Bruker BioSpin GmbH, NMR Division, Rheinstetten, Germany

NMR spectroscopy is introduced for the quality control and authenticity assessment of beer in official food control. Measurements were performed at a F 400 MHz NMR spectrometer using flow injection technology for automatic sample changing. For preparation of the beer samples, only degassing and addition of buffer (pH 5.6 in D2O with 0.1% TSP) is required. Each spectrum was acquired at a temperature of 303K, using various Pre-Saturation pulse sequences.
The variability of the spectral profile of beers differing in type and origin was studied by principal component analysis (PCA) considering the spectrum as a characteristic fingerprint. For the first time, the high throughput of a Flow-Injection NMR system allowed the efficient establishment of a comprehensive database of beer spectra for PCA classification. Beers made with barley malt and wheat malt could be distinguished. A clustering of beers from the same brewing sites was observed. Deteriorated beers with flavour taints or bacterial contamination could be discriminated from normal products. Using the Partial Least Squares (PLS) method to correlate NMR spectra with results from reference methods (refractometry/densitometry and enzymatic analysis), models for calculation of ethanol, original gravity and lactic acid content of the beer samples were established.
The results obtained suggest that NMR is a useful tool for the quality control of beer samples, since quantitative determination of all essential compounds as well as chemometric classification is possible by a single experiment. Compared to conventional methods, 1H NMR spectroscopy is faster and requires only simple sample preparation.
 
17 - ESR AND NMR SPECTROSCOPY STUDIES ON EMULSIONS CONTAINING Β-LACTOGLOBULIN AND OXIDISED METHYL LINOLEATE

Suhur Saeed, Nazlin Howell, D. Gillies
School of Biomedical and Molecular Sciences, University of Surrey, Guilford, Surrey GU2 7XH, United Kingdom

Proteins including β-lactoglobulin (β-LG) contribute to the emulsification and gelling properties of food products due to their specific structure as well as interactions with other components during processing.  The effect of lipids, especially oxidising lipids, on the structure and function of -LG has not been investigated in detail.

 

Spin label 2-methyl-2-nitrosopropane in 25mM DMSO was incubated with the emulsion containing β-LG (15%) and oxidised methyl linoleate (ML) (10%) in the presence or absence of antioxidants.   ESR spectra, recorded on a Jeol RE IX X-band spectrometer indicated a spin trap radical adduct initially in the lipid phase; this was subsequently transferred to the protein layer. After 24 h this immobilised nitroxide radical reached its maximum intensity and remained stable at -20˚C, but decreased when stored at 22˚C. Antioxidants prevented the transfer of the radical to the protein. ESR signals were not detected in the absence of oxidised ML or with fresh ML, indicating that the detected nitroxide radical depends on the hydroxyl radical produced from oxidised ML. Only a three-line ESR spectrum was observed, with no additional hyperfine coupling, indicating that the radical is centred on a tertiary carbon. Tyrosine and tryptophan residues provide two likely possibilities for the formation of a radical adduct that would yield the primary triplet observed in this study.

 

2D 1H NMR spectra showed changes in structural flexibility and amide groups and interactions between β-lactoglobulin and oxidised ML.  Changes in the amide 1 and 111 regions, tryptophan and tyrosine doublet bands were also confirmed by FT-Raman spectroscopy.

This study highlights the significant effect of lipid oxidation products on protein structure and function.

 

Acknowledgements: BBSRC funding to Prof. Nazlin Howell is gratefully acknowledged.

 
18 - NUTRITIONAL COMPONENTS IN COD (GADUS MORHUA) MUSCLE AND CHANGES DUE TO FREEZING AND THAWING EXAMINED BY HR 1H MR SPECTROSCOPY

Standal, I.,Gribbestad, I S., Bathen, T., Halvorsen, J, Aursand, M, Martinez, I.
SINTEF Fisheries and Aquaculture, Ltd, Cancer Clinic, St. Olav Univerisity Hospital, SINTEF Unimed, Norway

Lipids (PUFAs) and metabolites (anserine, carnosine, taurine, betaine, choline) determine the mouth feel and taste of seafoods. They also have positive effects on human health. All these components can be identified by HR 1H MR spectroscopy, a sensitive technique with short acquisition times that produces a fingerprint with the potential to be used to identify the sample and its history.
Our group is involved in the development of methods for the (1) non-destructive compositional analyses and (2) authentication of seafoods. We present here the results corresponding to the characterization by 1D and 2D 500MHz 1H MR spectral analyses of perchloric acid extracts (PCAE) from pre-rigor white muscle of cod (Gadus morhua) and the effect of freezing and thawing on the metabolite content of cod muscle.
We could identify single components including: lactate, alanine, anserine, TMA, TMAO, creatine, choline, glycine, β-alanine, taurine, hypoxanthine and formate. The singlet arising from TMAO and the numerous signals from anserine dominated the spectra. The present study also showed that freezing and thawing affects the metabolite content in cod fillets as well as the components lost as "drip-loss".
Currently, a database is being constructed in order to classify unknown samples according to their biochemical composition: by suitable multivariate data-analyses of the spectra we intend to extract information such as species, origin, feed, production method, processing and nutritional value of seafood products.
 
19 - SIMULTANEOUS MAPPING OF STRUCTURAL- AND TEMPERATURE-CHANGES DURING HEATING OF FOOD IN WATER BY MRI

Kevin P. Nott 1, Andreas Hauri 2, Laurance D. Hall 1
1 University of Cambridge, UK, 2 Swiss Federal Institute of Technology, Zurich, Switzerland

Although, a large amount of research has involved modelling of the often interrelated heat- and mass-transfer processes associated with thermal processing [1] as well as the moving boundary associated with structural- and phase-changes [2], the limited processing power of computers often requires assumptions to decrease calculation times. Therefore, there is a need for measurement techniques that can acquire data for processes that are too complicated to model, as well as to validate the models themselves. Fortunately, Magnetic Resonance Imaging (MRI) can map temperature distributions [3] as well as other heat induced changes; as shown in a previous study of microwave heating off-line [4]. This current study demonstrates that MRI can be used to acquire multivariate data associated with heating by water on-line. Specifically, not only to map temperature, but simultaneously visualise the gelatinisation front during cooking of potato, or the thawing front during heating of a frozen ‘boil in the bag’ bolognese sauce. The future prospects for other experimental studies as well as for using such data are discussed.

1. Wang, L.J. and D.W. Sun, Trends in Food Science & Technology, 14, 408-423, 2003.
2. Singh, R.P., Food Technology, 54, 44-54, 2000.
3. Nott, K.P. and L.D. Hall, Trends in Food Science & Technology, 10, 366-374, 1999.
4. Nott, K.P., S.M. Shaarani, and L.D. Hall, in Magnetic Resonance in Food Science: Latest Developments, P.S. Belton, et al., Editors, Royal Society of Chemistry: Cambridge. p. 38-45, 2003.

  

 
20 - WHEAT FLOUR ENZYMATIC AMYLOLYSIS MONITORED BY IN SITU 1H-NMR SPECTROSCOPY

Maria E. Amato a, Giuliana Ansanelli b, Salvatore Fisichella a, Raffaele Lamanna b, Giuseppe Scarlataa, Anatoli P. Sobolev c, Annalaura Segre c
a) Dipartimento di Scienze Chimiche Università Viale A.Doria 6 - 95125 Catania, Italy
b) CR ENEA Trisaia UTS Biotec-Agro SS 106 Jonica Km 419.5 - 75026 Rotondella (Mt), Italy
c) Institute of Chemical Methodologies, CNR, M.B. 10, 00016 Monterotondo Stazione (Rome), Italy

Starch enzymatic degradation caused by endogenous hydrolases is studied by in situ NMR spectroscopy on a set of hard and soft wheat flours. The results obtained by two different techniques (HR-MAS and 1H-NMR in solution) are analyzed in term of a Michaelis-Menten kinetic phenomenological model taking into account the presence of endogenous enzymes and their eventual inactivation. The parameters resulting from the best fit of all experimental data to the kinetic model equations are submitted to a multivariate statistical analysis in order to assess the role of the oligosaccharides release in distinguishing between hard and soft wheats.
 
21 - IDENTIFICATION OF PHENOLIC COMPOUNDS IN OLIVE OIL BY LIQUID CHROMATOGRAPHY WITH NUCLEAR MAGNETIC RESONANCE (LC NMR)

Photis Dais*, Stela Christoforidou, Manfred Spraul
NMR Laboratory, Department of Chemistry, University of Crete, Bruker-Biospin GmbH, Germany

This work describes the first application of LC-NMR to the direct identification of phenolic compounds in the polar part of virgin olive oil. This hyphenated analytical technique, which combines the properties of the most powerful separation technique (HPLC) with the most information-rich spectroscopic technique (NMR), was able to identify a large number of phenolic compounds, including simple phenols (hydroxytyrosol, hydroxytyrosol acetate, tyrosol, tyrosol acetate, p-coumaric acid, vanillic acid, vanillin), secoiridoids (oleuropein and ligstroside derivatives of hydrolysis), lignans [(+) pinoresinol, (+) 1-acetoxypinoresinol], and flavonoids (apigenin and luteolin). Through the time-sliced 1D 1H NMR spectra, and a few TOCSY and HMQC experiments, a comprehensive assignment of the various signals was obtained for most of the isomers of the secoiridoids carboxylated and decarboxylated derivatives, and those of elenolic acid. Moreover, new chromatographic peaks were identified and attributed to homovanillyl alcohol, syringaresinol and maslinic acid.
 
22 - APPLICATION OF FTIR AND NMR SPECTROSCOPY FOR THE DETERMINATION OF ORIGIN AND DATE OF PRODUCTION OF BEER

Cláudia Almeida, Iola F. Duarte, António Barros, Ana M. Gil
Department of Chemistry, University of Aveiro, Portugal.

In this work, Principal Components Analysis (PCA) is applied to the FTIR-ATR and 1H NMR spectra of a set of beers manufactured in 3 different countries, at different dates, in order to find out if the spectral parameters of beer may be consistently correlated to origin and date of production.
PCA of FTIR data separated beers from site 1 from the remaining ones, this separation being based mainly on differences in alcoholic content. No significant differences were found as a function of production date, with the exception of the beers of site 2 which seem to differ slightly in terms of dextrins composition.
Performing PCA on separated NMR regions, the scores scatter plot of PC1 vs. PC2 of the aliphatic spectral region indicates very good separation of all samples according to their production sites. The corresponding loadings indicate that such clear distinction is due to changes in some amino acids, alcohols and organic acids, thus indicating these compounds as exquisitely dependent on variables related to the production sites. Secondly, the PCA of the sugar region shows that the average number of dextrins branching points/molecule also correlates to production site and, in some cases, to manufacturing date. Finally, PCA of aromatic region is successful in separating beers according to both their production site and date.
These results open the interesting possibility that tandem use of chemometrics and spectroscopy may provide rapid information about the origin of beer (geographical and production date), which may be of great value in accessing the reproducibility (and thus for quality control) within different brewing sites.

ACKNOWLEDGEMENT
The authors thank Bruker BioSpin GmbH for funding support.
 
23 - STUDIES OF FISH FREEZING USING MR IMAGING

A. Borge 1, T. Singstad 1, V. Hardarson 2, L. Jørgensen 3, I. S. Gribbestad 4
1) Dept of Radiology, St. Olavs Hospital, Trondheim, Norway.
2) Dept of Energy and Process Technology, NTNU, Trondheim, Norway.
3) SINTEF Energy Research, Trondheim, Norway.
4) The Cancer Clinic, St. Olavs Hospital, Trondheim, Norway.

MR imaging offers a unique tool for calibrating mathematical models and numerical simulations of thermal processes in food products. A quantitative understanding and the development of on-line measuring methods of freezing and thawing, are of crucial importance for the fish farming industry. Dynamic MR temperature and ice content maps will facilitate this and may thus lead to optimised production parameters and improved quality and processing properties of the fish. The aim with this study was to map the feasibility of MRI as a method for producing this kind of images.

A home-made nitrogen cooling device for small fish samples was used inside a Bruker Biospec 2.4 T scanner. Thermoelements were used to registrate sample and cooling temperatures. We stepped through a range of temperatures to take MR pictures at stationary temperature conditions. Also one big temperature step was performed to “film” an ordinary transient freezing procedure. Samples of cod and Atlantic salmon were studied in the typical ranges (+10ºC,-10ºC/-20ºC), respectively. In the stepwise regime an image with very short echo time (2-3 ms) was obtained and T1 and T2 maps made (ROI-level). Spin density and ice fraction maps were calculated (cod). Both T1, T2, and spin density drop in a hyperbolic way when reducing temperature beyond freezing. Probably this is connected to gradual freezing point depression due to increased concentration of salts and macromolecules. Correspondingly, a more or less sharp “ice-front” is seen moving in our transient measurements. For salmon the MR fat signal component survives very cold conditions.

 
24 - BLENDS ANALYSIS OF ARABICA AND ROBUSTA RAW COFFEES SPECIES THROUGH 1H NMR AND CHEMOMETRIC METHODS

Leila Aley Tavares 1, Elisangela Fabiana Boffo 1, Antonio Gilberto Ferreira 1, Márcia Miguel Castro Ferreira 2, Luiz Henrique Capparelli Mattoso 3, Alessandra Alves Corrêa 3
1 UNIVERSIDADE FEDERAL DE SÃO CARLOS, 2 UNIVERSIDADE DE CAMPINAS, 3 EMBRAPA, BRAZIL

The drink coffee is prepared from arabica or robusta variety grain, or even from blends of them. Arabica variety presents flavor more pronounced and refined, so it can get a best price than robusta in the international trade. This increase the chance of frauds and require techniques that have power to discriminate both varieties in a blend.
In this work was used chemometric methods and 1H NMR spectroscopy data to discriminate arabica and robusta blends as much as classificatory and quantitative analysis.
The 1H NMR data were aquire in BRUKER 9.4 Tesla equipment and all measurements were done in triplicate. Were used eleven coffee samples without roast and with different contents of arabica and robusta specie. The chemometric methods used were: PCA and HCA for exploratory analysis, KNN and SIMCA for classificatory analysis, PCR and PLS for quantitative.
Results obtained showed that the methods of exploratory and classificatory analysis can group the blend samples correctly in two groups, one content less and the other high proportion of arabica specie. However the method KNN shows be better than SIMCA because it can discriminate the samples in two groups (arabica and robusta) without any error using ten neighbours. To predict the proportion of each variety in the coffee blend were used PLS and PCR methods and PLS showed better than the PCR . The same were done with roast coffee sample but the results were not so good because the roast degree made a strong influence in the chemometric analysis.
 
25 - SODIUM AND FAT DISTRIBUTION IN SMOKED SALMON IN RELATION WITH WATER DYNAMICS ACCESSED BY 1H AND 23Na MRI

L. Foucat 1, R. Ofstad 1, 2, J.P. Donnat 1, J.P. Renou1
1 INRA Theix. STIM. 63122 Saint-Genès Champanelle. France.
2 MATFORSK, Oslov1, 1430 Ås, Norway.

1H and 23Na MRI offer a unique opportunity to access non-invasively and concomitantly the distribution of fat and sodium. The aim of this work was to investigate the incidence of the fat distribution on the heterogeneity of the salt content in smoked salmon filet. To characterize the water dynamics in function of the salt distribution, parametric images of the transverse relaxation time T2 of water proton were also recorded.
MRI experiments were performed at 53 MHz (23Na) and 200 MHz (1H) on a Bruker Biospec imager (4.7 T). A homemade 105 mm 23Na/1H double tune NMR probe was specially designed for this investigation. Fat selective images were acquired with a pulse sequence based on the difference of longitudinal relaxation time T1 and chemical shifts between fat and water signals1. Because the rapid decline of the NMR sodium signal due to the very short relaxation time T2 (in the order of the ms), a gradient echo imaging sequence was used. 23Na MRI approach was preliminary validated on a phantom constituted by a series of tubes containing NaCl solutions of known salt concentration (ranging from 0 to 5 % w/w).
Study on smoked salmon filets with different salt and fat contents are reported, and relationships between fat, salt and T2 distributions are discussed.

  

 
26 - INVESTIGATION OF MARINE BIVALVES MORPHOLOGY BY IN VIVO MRI. FIRST ANATOMICAL RESULTS OF A PROMISING TECHNIQUE

L. Foucat 1, S. Pouvreau 2, M. Rambeau 3, J.P. Renou1
1 INRA Theix. STIM. 63122 Saint-Genès Champanelle. France.
2 IFREMER. Laboratoire de Physiologie des Mollusques Marins. Site Expérimental d'Argenton. Presqu'île du Vivier. 29840 Argenton en Landunvez. France.
3 Association pour les Technologies Nouvelles en Radiologie. Département de Radiologie et Imagerie Médicale. Hôpital Sud. 16, bd de Bulgarie. BP 90347. 35203 Rennes cedex 2. France.

Marine bivalves and especially the Pacific Oyster, Crassostrea gigas, are economically important in the French aquaculture. Now, its production has become a major industry with a production above 100 000 metric tons in 2002. Nevertheless, the ecology and the physiology of this bivalve are not really well known and consequently their growth and reproduction in field but also in hatcheries remain still empirical. Several scientific projects aim to improve this basis knowledge but new tools need to be discovered in order to take a step in knowledge acquisition rate.
Classically, the investigation of soft tissue in marine mollusks and especially in marine bivalves relies on destructive methods, since a hermetic shell protects the animal. These common techniques give precious information in marine mollusks biology and ecology but present two main inconveniences which may constitute a limiting step in specific studies: these methods are (1) really time consuming and (2) necessarily destructive. Therefore, noninvasive and quantitative procedures have recently become of interest. Among them and after preliminary trials, NMR imaging appears to be a promising way. The aim of the present study was (1) to provide the first results in NMR imaging on oyster (2) depict the anatomy with an optimal MR contrast parameter with the use of two NMR imagers (1.5 and 4.7 T) and (3) show the feasibility and the potentialities of this technique for future investigation of metabolism by 1H and 31P localized spectroscopy.

  

 
27 - COMPARATIVE STUDIES OF FOOD POLYMER HYDRATION BEHAVIOR

Catherine Shawl, Bruce Campbell
Kraft Foods R&D, USA

Time domain 1H NMR spectroscopy is used to study a range of food polymer systems, including flours, meat proteins, and dairy proteins. NMR relaxation rates are analyzed to determine the kinetics of polymer hydration. The influence of factors such as temperature, pH, and ionic strength are investigated. The relaxometry results are compared to traditional solubility measures as well as rheological data for these systems.
 
28 - NUCLEAR MAGNETIC RESONANCE IMAGING (MRI) – DETECTION OF INTERIOR DEFECTS IN PROCESSED PORK

Gunilla Lindahl 1, Hans Stødkilde-Jørgensen 2, Margit Dall Aaslyng 3, Michael Aagard 4, Anders H. Karlsson 5, Henrik J. Andersen 1
1 Department of Food Science, Danish Institute of Agricultural Sciences, Tjele;
2 Skejby University Hospital MR Research Centre, Aarhus;
3 Danish Meat Research Institute, Roskilde; 4Tulip Food Company, Vejle
4 Department of Food Science, Meat Science Unit, The Royal Veterinary and Agricultural University, Frederiksberg C. Denmark

The ever-increasing demand for high quality products has made it extremely important for the food industry to be able to supply products of pre-specified quality. In most food raw materials including meat, a high biological variation exists both within and between samples. This results in a high variation in processed products based on such raw materials. Porosity or a loose structure is often seen in cooked meat products. These features are important quality defects in the production of sliced meat products. The reason for formation of holes is far from understood. Consequently, development of non-destructive methods for detection of interior quality defects is therefore highly desirable. MRI is one of the few available imaging techniques, which can identify interior defects in a non-destructive way.

The present study aimed to clarify the possibility to detect porosity in cooked cured ham using MRI. Cooked hams (n=76) were scanned in 3 mm slices with 6 mm distances in a whole body magnet (GE, 1.5 Tesla). The porosity was detected in T1 weighted images (T1 Flair sequence). The hams were then sliced in 3 mm slices and the quantity and the size of the pores were visually judged by a sensory panel. The correlation between the number of holes assessed by the sensory panel and the MRI images is investigated.

The study is part of the project ‘Characterization of technological and sensory quality in food by NMR’, which is supported by the research program ‘Food technology, safety and quality’ and funded by the Ministry of Food, Agriculture and Fisheries.
 
29 - HIGH RESOLUTION IMAGING OF FAT DISTRIBUTION IN MEAT USING 3D-PGSE

J.M. BONNY, J.P. RENOU
STIM, INRA, France

MRI has no equivalent for analyzing the intramuscular fat (imf) distribution in a non-destructive manner. Imf influences some important meat quality characteristics e.g. marbling, sensory properties and keeping qualities as well as diffusion of water and salt in cured/smoked products.
A large number of sequences have been proposed for generating images of fat distribution which exploit the differences in T1 (e.g. inversion recovery) or/and resonance frequencies between fat and water (e.g. CHESS or Dixon phase-sensitive technique) 1.
We propose a new approach which takes advantage of the large difference between the apparent diffusion coefficients of myofibers and imf 2. Using a sufficiently large b-value, it is possible to attenuate the signal of water so that only the one of fat becomes detectable. The manner for selecting the adequate b-value according to the other MR parameters are discussed and an example of isotropic high resolution acquisition using a 3D-PGSE sequence is shown.

1. Laurent, W., Bonny, J.M., and Renou, J.P. Imaging of water and fat fractions in high field MRI with multiple slice chemical shift selective inversion recovery. Journal of Magnetic Resonance Imaging 12, 488-496 (2000).
2. Bonny, J.M., and Renou, J.P. Multiexponential modeling of diffusion in meat at large b-values by MRI. 7th ICAMRFS, Copenhagen (2004).

  

 
30 - THE USE SOLUTION NMR TO THE STUDY OF COUMA UTILIS – SORVA FRUIT

A. M. R. Nascimento a, M. I. B. Tavares a, R. S. Nascimento b
a Instituto de Macromoléculas Eloisa Mano, Universidade Federal do Rio de Janeiro, Cid. Univer., Ilha do Fundão, Rio de Janeiro, RJ, CP 68525, CEP 21945-970, Brasil
b Universidade do Estado do Amazonas, Manaus, AM, Brasil

Sorva, is a native fruit of Amazons State in Brazil. It has been very much used in gum industry. In order to maximise the uses of this fruit it is important to obtain information on chemical components present in it. Based on it, the main purpose of this work, is to investigated the fruit components using 13C {1H} solution nuclear magnetic resonance (NMR). For that, solvents with different polarities were used to extract the different fruit components at ambient temperature. Interesting and important data have been obtained to get information on chemical components of this fruit. We first extracted the components from the during ripening. The total fruit were put in different separation funnels and the solvents such as chloroform, water, dimethylsulfoxide and methanol were put in each one to extract the chemical components. Each extract were analysed by normal 13C solution NMR and some interesting data were obtained. From dimethylsulfoxide extract only polysaccharides were extracted. From chloroform extract signal from triacylglycerols and other components were collected. When water was used signals related to polysaccharide and triacylglycerol were acquired and for methanol the signals already detected for water were assigned.
 
31 - USE OF HR-MAS AND X-RAY TO STUDY THE GELATINIZATION PROCESS OF FRUIT SEED STARCHES

Paula de Miranda Costa, Maria Inês Bruno Tavares, Antônio Gilberto Ferreira, Cristina Daolio, Lucineia Vizzotto, Anderson Barison
IMA/UFRJ, - IQ/UFSCar, BRAZIL

Gelatinization process of native starches is an important point to understand some of the starches properties for food applications. The tropical fruits seeds starches gelatinization process has been follow by HR-MAS, using a 4 mm rotor in 9.4 Tesla Bruker equipment, and by X-ray. The natives starches as they are heterogeneous amorphous materials they present domains that are constituted by ordered and non-ordered polysaccharides chains. As far as we know that fruits seeds starches arrangements and compositions depend on the regions and clime, the gelatinization process was carried out after optical microscopic analysis and differential scanning calorimetry (DSC) measurements. The melting transition of starches crystals was determined by DSC and the values found for those were about 150°C. The gelatinization process was carried out at 150°C, which was higher than the gelatinization temperature used for potato and maize for instance. The samples were investigated by HRMAS and X-ray before and after being gelatinized and the HR-MAS showed more detailed information about this process concerning to the changes in the polysaccharides crystal structure than was observed by X-ray. The results obtained by HRMAS indicates that this analysis can be a new technique to be used as a absolute method to follow the changes in starches structure.
 
32 - MULTIVARIATE CHEMOMETRIC ANALYSIS OF MAGNETIC RESONANCE IMAGES IN RELATION TO FOOD QUALITY

Elisabeth Micklander 1, Frans van den Berg 1, Anette K. Thybo 2, Sune Jespersen 3, Hans Stødkilde-Jørgensen 3
1 The Royal Veterinary and Agricultural University, Department of Food Science, Food Technology, Frb. C., Denmark
2 Danish Institute of Agricultural Sciences, Department of food Science, Plant Food Science, Aarslev, Denmark
3 Aarhus University Hospital, MR Research Centre, Aarhus N, Denmark

Water characteristics and the anatomical interior of raw materials have been identified as the physical/chemical parameters of most importance for the technological and sensory properties of final (processed) food products. Magnetic Resonance Imaging (MRI) has potential for non-destructive determination of the water distribution in food-stuffs and non-invasive characterization of the inner structures. Accordingly MRIs contain potentially information on the sensory quality of the products.

In this study multiple MRIs (M0, T1, T2, Dx maps) were obtained on different potato varieties, which were simultaneously evaluated on 7 sensory texture attributes. The aim is to investigate the relation between the sensory qualities of the potatoes as determined by the trained panel and the complex MRI data using different chemometric factor models.

As often done in more traditional image analysis information is extracted from the images by estimating different features or intensity-distributions. The output from these image decompositions/transformations is used as input to chemometric multivariate factor models for comparison with individual sensory attributes or product maps based on all attributes.

  

 
33 - METABONOMICS STRATEGY FOR THE DETECTION OF THE EFFECTS OF THE CHAMOMILE (MATRICARIS RECUTITA L) IN TAKES

Yulan Wang 1, Huiru Tang 1, Jeremy K. Nicholson 1, Peter J. Hylands 2, J. Sampson 2, Elaine Holmes 1
1 Imperial College, 2 Oxford natural products, UK

We have applied an NMR-based metabonomics technique, utilising high-resolution 1H NMR spectroscopy in conjunction with advanced chemometric methods, to study human biological response to ingestion of chamomile tea. It was found that the biological response to chamomile tea intake was a weak event and was often obscured by the great diversity in physiological state and diet of the subjects. Application of Orthogonal Signal Correction (OSC) data filtration technique was necessary to remove such variations. A partial least square (PLS) model was subsequently built using OSC filtered data and the model was validated by successfully predicting a new dataset, which played no role in OSC filtration or model construction. The subtle changes induced by chamomile ingestion were extracted and characterised mainly by the increase in hippurate and the decrease in creatinine excretion. This study highlighted the benefits of applying data filtering methods to complex multiparametic biological data and demonstrated the sensitivities of NMR based metabonomic strategy in the application of studying subtle metabolic responses to food supplements

Keywords: NMR based metabonomics, chamomile, Matricaria recutita L, Orthogonal Signal Correction
Abbreviations: PCA: principal components analysis;
OSC: orthogonal signal correction;
PLS: partial least square;
TMAO: trimethylamine N-oxide;
DMA: dimethylamine;
TMA: trimethylamine;
 
34 - COOKING EFFECTS ON WATER DISTRIBUTION AND MOBILITY IN POTATOES USING NMR RELAXATION

Margit C. Mortensen 1, Anette K. Thybo 1, Hanne C. Bertram 1, Søren B. Engelsen 2, Henrik J. Andersen 1,
1 Dept. of Food Science, Danish Institute of Agricultural Sciences
2 Centre of Advanced Food Studies, Dept. of Food Science, Food Technology, The Royal Veterinary and Agricultural University, Denmark

The purpose of the present study was to follow the changes in distribution and mobility of water in potatoes during cooking using continuous low-field (LF) NMR T2 relaxation measurement on two bins of the potato cultivar Cv. ‘Sava’ with different dry matter content. The continuous LF-NMR relaxation measurements were carried out during heating (25°C to 99°C) over a period of 20 minutes using 22 temperatures points.
Principal component analysis (PCA) on the obtained NMR relaxation curves showed that the major changes in water mobility during the cooking took place at 53.2°C and 59.7°C for potatoes with high and low dry matter content, respectively. This transition temperature may be attributed to a softening of cell walls and an initiation of the gelatinisation process. In contrast changes in water mobility in both potato bins stopped at the same temperature (70.4°C), which most probably reflect termination of the gelatinisation process.
A more descriptive interpretation of data was obtained using discrete bi-exponential fitting on the obtained NMR data. The progress in the two identified relaxation components T21 and T22 throughout the cooking process indicated that the slowest relaxing relaxation component (T22) originates from relatively free water representing the vascular tissue used for water transport in the potato during growth. In contrast, the more complex behaviour of the fastest relaxing component T21 seems to reflect intracellular water in the relative non-restricted environment before gelatinisation of the starch (‘raw potato’) and intracellular water in a more restricted environment after gelatinisation (‘cooked potato’).
In conclusion, the present study demonstrates that continuous LF-NMR measurements is an excellent and sensitive method to determine changes in water mobility and water populations during cooking of potatoes, which moreover allow differentiation of these events in potatoes of different qualities. This study reveal the potential of LF-NMR to obtain information of considerable importance for a basic understanding the influence of processing on gelatinisation and texture of cooked potatoes in relation to variability in raw material quality.
 
35 - NON-DESTRUCTIVE DETECTION OF INTERNAL BRUISE AND SPRAING DISEASE SYMPTOMS IN POTATOES USING MAGNETIC RESONANCE IMAGING (MRI)

Anette K. Thybo 1, Sune N. Jespersen 2, Poul Erik Lærke 3, Hans J. Stødkilde-Jørgensen 2,
1 Dept. of Food Science, Danish Institute of Agricultural Sciences, DK-5792 Aarslev,
2 Aarhus University Hospital, MR Research Centre, DK-8200 Aarhus N.
3 Dept. of Agroecology, Danish Institute of Agricultural Sciences, DK-8830 Tjele, Denmark

Magnetic resonance imaging (MRI) was applied to detect non-visible internal bruise and spraing symptoms and to get insight in the chemical and anatomical cause for such defects. Cv Saturna with internal bruise and cv Estima with spraing symptoms were investigated by comparison of different MR images as proton density-, T1 weighted- and T2 weighted images and T2 maps. Each of the MR images was able to probe the presence of internal bruise and spraing spots. When combining the information in the MR images the interior of the internal bruise was characterised as being very dry (low signal in the proton weighted image) with a small amount of highly mobile water in the rim around the bruise (high signal in T2 weighted image and high relaxation time in T2 map). The appearance of the spraing spots were more diffuse, however a dry interior and presence of highly mobile water around the spraing dots was somewhat similar to the appearance of internal bruise but resembled more the appearance of human brain disorders than bruise disorders in e.g. fruits. In conclusion, this study showed that MRI detected non-visible internal bruise and spraing symptoms in potatoes, which has not been published before. MRI may therefore be an appropriate method for detecting and for studying developmental changes of such disorders and related disorders during postharvest storage in future experiments.
 
36 - APPLICATIONS OF OLFACTOMETRY IN FOOD SCIENCE

Isabel O. Lopez 2, Per Møller 2, Lise R. Nissen 2, Ep Köster 1, Frans van den Berg 2, Magni Martens 2, Wender L. P. Bredie 2
1 (Professor Emeritus) Utrecht University, Utrecht, The Netherlands
2 The Royal Veterinary and Agricultural University, Department of Food Science, Denmark

A computer-interfaced dynamic olfactometer has been developed at the Sensory Science group, KVL. The olfactometer is a versatile odour mixing machine, with a capacity of 54 odour-intensity combinations, originating from six channels each at nine different concentrations. The equipment allows changes in odour composition or intensities to be delivered instantaneously to human subjects. Examples of on-going research projects are presented, showing the versatile applications of the olfactometer both in applied and basic sensory research.

Interaction of memory and perception. This fMRI-study is aimed at localizing brain areas involved in incidental learning and memory of odours in young and elderly human subjects.

Odour threshold determination. This study measured odour detection thresholds for a series of structurally-related monoterpenes by recording the percentage correct responses from subjects at different odorant concentrations and by measuring the subject’s time needed to respond.

Quantification of odorant delivery. In this study an odorant trapping GC-MS method was developed to estimate the concentration of the odorants in the air-stream reaching the subjects’ nostrils.

Odour adaptation. This study investigated odour adaptation and recovery after odour stimulation for a series of structurally-related monoterpenes using a time-intensity method. Large individual differences in adaptation as well as recovery times were observed. Further work is undertaken to study the effect of the odorants.

Odorant mixtures. The objective of this study was to investigate the contribution of six odorants known from lipid oxidation to the total perceived mixture intensity and their impact on specific sensory attributes.

  

 
37 - THE EFFECTS OF EMULSION FORMATION ON NMR SPECTRA

Poul Erik Hansen, Philip W. Kuchel
Department of Life Sciences and Chemistry, Roskilde University, P.O.Box 260 DK-4000 Roskilde, Denmark
School of Molecular and Microbial Biosciences, University of Sydney, New South Wales 2006, Australia

Emulsions are a widely occurring phenomenon in foods and related to that as compartments of spherical shape in tissues.  The effects of emulsion formation on 1H chemical shifts will be discussed in terms of differences in magnetic susceptibility and a simple method describes how to estimate such effects using the Frei-Bernstein set up.

Effects of changing from a diamagnetic to a paramagnetic environment are illustrated as this may be of relevance to measurements of meat.

The use of 19F NMR in such measurements is discussed.

   (PDF)

 
38-40 - STUDY OF THE BEHAVIOR OF AMINO ACIDS IN AQUEOUS SOLUTIONS BY TIME DOMAIN-NMR AND HIGH RESOLUTION NMR (3 POSTERS)
M. Khallouk, D. N. Rutledge*, B. P. Hills
M. Khallouk, D. N. Rutledge*
M. Khallouk, D. N. Rutledge*, A. M. S. Silva, I. Delgadillo
INRA / INA P-G, UMR Ingénierie Analytique pour la Qualité des Aliments (IAQA)
BBSRC Institute of Food Research, Colney Lane, Norwich NR4 7UA, U.K.
Universdad de Aveiro, Departemento de Quimica, 3810-193 Aveiro, Portugal

Amino acids, peptides and the proteins are significant components of food. In this study, we concentrated more particularly on the characterization of the behaviour of amino acids as a function of pH in aqueous solutions, using Time Domain-Nuclear Magnetic Resonance (TD-NMR) and High Resolution NMR spectroscopy. The chemical exchange of protons between water and solutes with labile protons such as amino acids is a significant mechanism affecting the proton transverse relaxation of water.

The interest of this research is to characterize the phenomenon of proton exchange between the solvent (water) and the groupings of exchangeable protons of amino acids. This exchange is controlled by the intermolecular interactions existing between the various groupings of the molecules and the solvent. These interactions can be very important in biological processes such as enzymatic catalysis, and in determining the structure and function of proteins.

Measurements of transverse relaxation rates of the water protons (R2 = 1/T2) in aqueous solutions of amino acids such as L-glycine, L-asparagine and L-arginine were done in order to study the effects of chemical exchange and diffusion on the amplitude of R2. The relaxation curves were acquired using a Time Domain-NMR apparatus at a frequency of 20 and on a 100 MHz spectrometer.

R2 values are measured using the Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence at different values of pH, temperature and concentration, using a range of inter-pulse delays for both magnetic field intensities.

The same samples are used to acquire the corresponding protons spectra using a 300 MHz NMR spectrometer.

 

Three posters are presented showing different results obtained during this series of experiments. 

1) Characterization of the phenomenon of proton exchange and molecular diffusion in aqueous solutions of glycine by Time Domain-NMR at 20 and 100 MHz.

2) Effect of the pH and the temperature on chemical exchange and diffusion in aqueous solutions of glycine by Time Domain-NMR at 20 MHz.

3) Study of the behaviour of amino acids in aqueous solution by Time Domain-NMR and High Resolution NMR.

        

 
41 - CHANGES IN PROTON AND CARBON-13 NMR OF WHEAT AND SOY BREADS DURING STORAGE

Stefano Tiziani, Yu Chu Zhang, Yael Vodovotz
Food Science & Technology Department, The Ohio State University, Columbus, Oh 43210, USA

Addition of soy to wheat bread has been shown to affect the physico-chemical properties of the final product. To better understand the molecular changes during storage imparted by the addition of soy to bread, NMR was used. The changes in proton and carbon-13 NMR of a wheat (control) bread and a soy containing (60% of wheat flour replaced by soy ingredients) bread during storage at 4°C for 7 days were studied. Bread samples were placed in 5 mm tubes and 1H Cross Relaxation measurements were performed on a Bruker 300 MHz liquid NMR and 1H T1 and 13C measurements were performed on a 600 MHz NMR. There were more solid like 1H’s and decreased 13C mobility in wheat bread than soy bread. The solid like protons and 13C in wheat bread did not change during storage while this proton population decreased after 4 days of storage in the soy bread. Wheat bread had a greater 1H T1 than soy bread and its value did not change much during storage. The soy bread 1H T1 increased slightly during the first few days of storage. These results indicate that the addition of soy to bread significantly influence the proton and carbon-13 mobility and therefore will impact storage stability.
 

42 - On the use of low field NMR methods for the determination of total lipid content in marine products

Geir Humborstad Sørland, Per Magnus Larsen, Frank Lundby, Henrik W. Anthonsen, Bente Jeanette Foss

Anvendt Teknologi A/S, Matforsk, Norwegian University of Science and Technology, NTNU, Norway

Anvendt Teknologi A/S, Hagebyv. 32, N-9404 Harstad, Norway

Carr Purcell Meiboom Gill (CPMG) pulse sequences and multi Pulsed Field Gradient Spin Echo (PFGSE) sequences have been applied to determine the total lipid content in fish, fish feed, and marine powders. It was found that with low resolution equipment and the use of an optimized CPMG sequence it is possible to quantify the total amount of lipids present in the sample. Further, it is possible to discriminate between two classes of lipids in dried samples: Lipids with short T2 (~ 0.3 ms) and lipids with long T2 (~100 ms). We also show that there is a correlation between the lipids with short T2 and the amount of lipids bound to the solid matrix in the sample while the lipids with long T2 can be assigned to the amount of lipids in a liquid state.

 

Keywords: Quantification, lipid, phospholipid, marine products, low field NMR

 
43 - MRI and NMR spectroscopy study of post-harvest maturing coconut
Nikolaus Nestle a, Arthur Wunderlich b, Reinhard Meusinger c
a TU Darmstadt, Institute of solid state physics
b University Ulm, Division of Diagnostic Radiology
c TU Darmstadt, NMR division, department of chemistry
The coconut (Cocos nucifera) is a major agricultural product of many tropical regions of the world. It is consumed both in green stage (where the coconut water provides an excellent refreshing beverage) and in mature stage (when the fibrous, fatty pulp is the product of interest). Dried coconut pulp is used for the extraction of its oil which is for nutritional, cosmetic and other purposes. Despite its economic importance and its convenient size for MRI studies in clinical MR systems, only very few MRI studies on coconuts can be found in the literature [1,2] In both cases, only images obtained on mature coconuts were published. Furthermore, only cursory remarks on the structure of the pulp layer in coconuts can be found in [1], and no study of the maturation process on one coconut is known to us.

We have studied the maturation process of green coconuts still contained in their outer, fibrous pericarp by various MRI contrasts. Notable findings include the slow and spatially very inhomogenous drying of the pericarp, the internal structure of the pulp layer and the observation of the deposition of the pulp layer within the maturing coconut. Furthermore, the onset of the germination process in the maturing nut could be observed, too.

In addition to MRI studies, coconut water and pulp samples were taken from two MRI-examined coconuts at different maturation stages and subjected to 1H and 13C high-resolution and solid-state spectroscopy experiments. In these experiments, a striking similarity between the spectra of the young, immature pulp and of the water in a more mature coconut was observed. The main components in the green coconut water were identified as glucose and fructose, while the major part of the sugars in the mature coconut’s water was found to be saccharose.

[1] Jagannathan N.R., Govindaraju V, Ragunathan P 1995 In vivo magnetic resonance study of the histochemistry of coconut (Cocos nucifera) Magnetic Resonance Imaging 13 885-892
[2] Schick F 2001 Excitation of narrow frequency bands with reduced relaxation-related signal losses: Methodology and preliminary applications Magnetic Resonance Imaging 17 527-536
 
44 – BALASAMIC VINEGAR AND AGE MARKERS: 1H NMR STUDIES

Roberto Consonni1, Alberto Gatti2

1 Laboratorio di NMR, ISMAC, CNR Milano, Via Bassini 15, 20134 Milano, Italy

2 Divisione Sensory & Costumer Analysis, NEOTRON S.p.A. Stradello Aggazzotti 104, 41010 S.MARIA DI MUGNANO – Modena, Italy

 

Vinegars are typically produced by microbiological fermentation of ethanol containing substrates, whose origin composition characterize different vinegar types. The Italian traditionally produced balsamic vinegars require specific wine matrixes and well defined production methodologies.

Due to the nature of the production, traditional balsamic, balsamic and commercial vinegars contain substances that can be use as age markers. Here we present the use of 1H NMR studies combined with statistical approaches for the age determination.

 
 45 – 1H HR–MAS NMR FOR DETECTION OF FISH MEAL ADULTERATION

Marc Bassompierre, Petersen D.G., Nørgaard L., Viereck N., Humpher E. and Engelsen S.B.

Food Technology, Department of Food Science, The Royal Veterinary and Agricultural University, Denmark

This study represents a preliminary investigation of the potential of 1H HR–MAS NMR and NIR for alternative, rapid and objective assessments for detection of fish meal (FM) adulteration by meat and bone meal (MBM). Currently, the official method is a cumbersome near-subjective microscopic analysis of acid-boiled samples aimed at detecting illicit bone fragments of bovine origin in FM samples. This microscope-based analysis relies on skilled and experienced technicians, takes hours and its reliability may be questioned. The BSE crisis resulted in 1999 in a full ban of MBM and a partial ban concerning the use of FM in plants manufacturing bovine feeds (99/517/EC). This latest ban was a consequence of illegal practices, adulterating FM with MBM and the related lack of efficient detection methods. Consequently, we investigated several analyses in combination with chemometric analyses as potential control methods. The alternative methods studied were: 1) Nuclear Magnetic Resonance (1H HR-MAS NMR), 2) visible and 3) Near Infrared Reflectance Spectroscopy (NIR) and 4) lipid pattern recognition by GC-FID.

 

For this purpose, five FM from different origins (Denmark, Norway and Peru) and five Danish manufactured MBM were mixed together. The investigated set represented different combinations of the following concentrations: (0, 0.1, 0.5, 2, 5, 10, 15, 20, 60 and 100% MBM). Interval Partial Least Squares Regression (iPLS) was employed for screening and evaluation of the different analyses investigated. In conclusion, it appeared that the main variation between samples was due to differences in the lipid composition. Moreover, whereas NIR did not perform as well, 1H HR-MAS NMR appeared to be of potential interest for detecting adulteration of FM by MBM.

  

 

 

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