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Summary Home-scale and commerical mawe samples produced in urban Benin were very similar in composition, particle size, dough viscosity, and microbial loads, with titratable acidity 1.2-1.4% w/w (as lactic acid); home-produced mawe had a slightly higher pH (4.2), protein, fat, fibre, and ash than commercial mawe. Lactobacilli and yeasts predominated in both.

Summary Iota carrageenan, carboxymethyl cellulose and xanthan were used as additives (5 g/kg) in the manufacture of different types of minced fish products (fish chips and fish sticks). Samples of these products were stored at — 18°C and were evaluated at regular intervals for weight loss, fat uptake, physical properties, formation of dimethylamine and formaldehyde and sensory properties. All additions had a significant cryoprotective effect on weight loss and texture during frozen storage. Sensory attributes correlated well with the instrumental measurements of texture and weight loss. After 8 months of frozen storage, the fish chips with carboxymethyl cellulose and xanthan were significantly preferred to the controls. After 14 weeks of frozen storage, the fish sticks with iota carrageenan were not significantly preferred to the control. Xanthan was not a suitable additive for this type of product. Iota carrageenan, and to some extent carboxymethyl cellulose, decreased fat uptake during frying.

Curculigo pilosa is traditionally used in the manufacture of sorghum beer in West Africa. β-Amylase was purified 100-fold with 38% yield from a crude extract, giving final specific activities of 4850 U/mg and 5650 U/mg using soluble starch and p-nitrophenyl maltopentaoside, respectively, as substrates. The molecular mass of the monomeric enzyme was 64 kDa and its pI 4.2. Both activity and thermostability are higher than reported for other plant β-amylases. The catalytic efficiency was lower for amylose than for starches and amylopectin. In contrast to other plant amylases, the β-amylase from C. pilosa is able to degrade raw starches from wheat, corn, potato and rice. In this respect, it resembles β-amylases from microbial origin. This property, and its high activity and stability, explain its traditional use in the manufacture of infant food and sorghum beer in Burkina Faso and could make it applicable for other biotechnological purposes.

Pectins are a class of heterogeneous polysaccharides used in the food industry as a result of their ability to form gels. They are primarily composed of a (1→4)-α-D-galactopyranosyluronic acid backbone where the carboxylic acid group is methyl esterified at a level which depends on the source of the pectin and processing conditions used to isolate the material. Of considerable interest is the distribution of the free acid and methyl ester groups along this polymer chain. NMR spectroscopy, coupled with statistical analysis, is a powerful technique for the study of sequence distribution of monomers. Experimental conditions (temperature, pD) are reported which are appropriate for the analysis of pectic polysaccharides. Results are presented from a study of sequence distribution in native, modified, and fractionated pectins using 1 H and 13 C solution NMR methods. The triad sequence information was examined using Bernoullian and Markovian probability models in conjunction with continuous Gaussian distribution and discrete models. Intermolecular heterogeneity in pectins results in triad frequencies which reflect the distribution of acid and ester monomers for native and base saponified pectins. Fractionation of pectin through physicochemical methods and subsequent spectroscopic analysis provide insight into this heterogeneity. Segregation into discrete polymer populations shows a structural diversity best approximated by a 3-component statistical model.

Feruloylated arabinoxylans isolated from wheat flour and wheat bran were compared in their cross-linking behaviour with respect to viscosity properties and cross-linking products formed when various oxidative agents were applied to dilute solutions. Optimal conditions for each oxidative agent were investigated. In case of hydrogen peroxide and peroxidase, similar conditions were found for both types of arabinoxylans but wheat bran arabinoxylans gave a larger viscosity increase upon cross-linking than those of wheat flour. When glucose, glucoseoxidase and peroxidase or ammonium persulphate were used as oxidative agents, differences in the concentration of reagent needed to induce cross-linking and in viscosity increase were observed. The distribution of coupling products for both types of arabinoxylans and the different oxidative treatments was approximately 5 : 3 : 1 : 1 for 8-5, 8-O-4, 8-8 and 5-5, respectively. The low ferulate recovery after oxidative treatment was assumed to be caused by formation of unknown compounds, such as higher oligomers and lignin-linked products. A 1 : 1 mixture of flour arabinoxylan and feruloylated pectin showed a maximum synergistic effect on viscosity upon oxidative treatment using hydrogen peroxide and peroxidase. Both polysaccharides were shown to participate in cross-linking.

Soybean meal, soybean water unextractable solids (WUS) and extracts thereof, which contain particular cell wall polysaccharides, were incubated with a number of cell wall degrading enzymes. The intact cell wall polysaccharides in the meal and WUS were hardly degradable, while the extracts from WUS were well degraded. The arabinogalactan side chains in the pectin-rich ChSS fraction (Chelating agent Soluble Solids) could to a large extent be removed from the pectins by the combined action of endo-galactanase, exo-galactanase, endo-arabinanase and arabinofuranosidase B. The remaining polymer was isolated and represented 30% of the polysaccharides in the ChSS fraction. Determination of the sugar composition showed these polymers to be very highly substituted pectic structures. It still contained 5 mol% of arabinose and 12 mol% of galactose, representing 7% and 12%, respectively, of the arabinose and galactose present in the ChSS fraction before degradation. Further, the presence of uronic acid (50 mol%) and of xylose (18 mol%) indicated the presence of a xylogalacturonan.

In the present study the influence of plasmin hydrolysis of β -casein ( β CN) on the foam and emulsion properties was tested. The hydrophilic, amphipathic and hydrophobic fractions produced by plasmin hydrolysis of β CN and fractionation of the hydrolysate, show clear differences in emulsion, foam and surface-active properties. The hydrophilic peptide possessed poor functional properties. The hydrophobic peptides from β CN showed interesting foam properties, especially at acidic pH. The amphipathic peptides exhibited improved emulsion-forming properties, compared to intact β CN. It seemed that the presence of the hydrophilic N-terminus (i.e. fragment 1–28) in these amphipathic peptides was important for their stabilising properties.

Carotenoid bioavailability depends, amongst other factors, on the food matrix and on the type and extent of processing. To examine the effect of variously processed spinach products and of dietary fiber on serum carotenoid concentrations, subjects received, over a 3-wk period, a control diet (n = 10) or a control diet supplemented with carotenoids or one of four spinach products (n = 12 per group): whole leaf spinach with an almost intact food matrix, minced spinach with the matrix partially disrupted, enzymatically liquefied spinach in which the matrix was further disrupted and the liquefied spinach to which dietary fiber (10 g/kg wet weight) was added. Consumption of spinach significantly increased serum concentrations of all-trans-beta-carotene, cis-beta-carotene, (and consequently total beta-carotene), lutein, alpha-carotene and retinol and decreased the serum concentration of lycopene. Serum total beta-carotene responses (changes in serum concentrations from the start to the end of the intervention period) differed significantly between the whole leaf and liquefied spinach groups and between the minced and liquefied spinach groups. The lutein response did not differ among spinach groups. Addition of dietary fiber to the liquefied spinach had no effect on serum carotenoid responses. The relative bioavailability as compared to bioavailability of the carotenoid supplement for whole leaf, minced, liquefied and liquefied spinach plus added dietary fiber for beta-carotene was 5.1, 6.4, 9.5 and 9.3%, respectively, and for lutein 45, 52, 55 and 54%, respectively. We conclude that the bioavailability of lutein from spinach was higher than that of beta-carotene and that enzymatic disruption of the matrix (cell wall structure) enhanced the bioavailability of beta-carotene from whole leaf and minced spinach, but had no effect on lutein bioavailability.

Graded ethanol precipitation of a wheat bran extract resulted in four fractions of glucuronoarabinoxylans, the physicochemical properties of which were investigated in relation to their structure and molecular weight. Two fractions, consisting of lowly-substituted arabinoxylans, appeared to be very sensitive to aggregation, and gave hardly any viscosity to solutions. Moreover, the viscosity of these arabinoxylans was not affected by addition of salt, nor by changes in temperature. Interaction with other polysaccharides, such as xanthan and κ-carrageenan, based on observations with quite similar lowly-substituted galactomannans, was not observed. Additionally, these arabinoxylans gave no stabilising effects to emulsions. The other two fractions consisted of highly-substituted glucuronoarabinoxylans, which had intrinsic viscosities of approximately 2.5 dL/g in 0.1 M potassium chloride. The viscosities were affected by temperature and addition of salt; the latter observation is in agreement with their polyelectrolyte nature. These polysaccharides appeared to be semi-flexible and not very sensitive to aggregation, although some aggregation was observed upon partial removal of arabinose substituents. Again, no interaction with xanthan and κ-carrageenan was observed for these fractions. However, they were very effective in stabilising emulsions.

In this study, predictions for growth rate of Listeria on food products were evaluated by both general applicable models and specific growth models. Literature values, obtained from a large number of publications, for growth rates in/on a variety of foods were compared by graphical and mathematical analysis with predictions given by various models. Apart for the great advantage of being generally applicable, the general models performed best. However, only small differences between the various models were observed. Model predictions were accurate within a factor of about two to four, depending on the type of product. The predictions should therefore not be considered as absolute; it is important to understand the limitations of the performance of models. All results and all assumptions should be criticised, but in many cases the accuracy will be sufficient to use these types of models as a tool in management decisions.

The interest in functional foods, probiotics and prebiotics requires a proper method to determine specific bacterial groups in the intestinal flora, especially bifidobacteria and lactobacilli. Three media for lactobacilli (MRS, Rogosa, LAMVAB), three media for bifidobacteria (RB, NPNL, Beerens medium) and nine media for total anaerobes have been tested for selectivity and recovery. For total anaerobes Faecal Reinforced Clostridial Agar (FRCA) showed the highest cfu/g, followed by Columbia Blood Agar and BHI Blood agar. There were no significant differences between the media tested. Reduced physiological salt solution was found to be the best dilution medium. For bifidobacteria and lactobacilli samples of human faeces, cat faeces and pig ileal contents were used. Bifidobacteria could reliably be determined on all three media tested in human faeces, but not on pig ileal contents or cat faeces. Absolute counts were highest in human samples. No lactobacilli could be isolated on MRS in either sample, none of the colonies in the countable plates were lactobacilli. For Rogosa over 90% of the colony types observed in human samples were not lactobacilli. For cat faeces this was 58%, but no false positives were observed in the pig ileal samples. For LAMVAB the percentages of false positive colony types were 9, 14 and 0% for human, cat and pig samples. It can be concluded that for bifidobacteria RB and Beerens medium show comparable results, and can be used to quantify bifidobacteria in human faeces, but none of the media tested is suitable for reliably counting bifidobacteria from pig and cat samples. For lactobacilli LAMVAB shows the highest sensitivity.

The formation of odor active compounds resulting from initial lipid oxidation in sunflower oil-in-water emulsions was examined during storage at 60 degrees C. The emulsions differed in initial pH, that is, pH 3 and 6. The volatile compounds were isolated under mouth conditions and were analyzed by gas chromatography/sniffing port analysis. The lipid oxidation rate was followed by the formation of conjugated hydroperoxide dienes and headspace hexanal. The initial pH affected the lipid oxidation rate in the emulsions: the formation of conjugated diene hydroperoxides and the hexanal concentration in the static headspace were increased at pH 6. Pentanal, hexanal, 3-pentanol, and 1-octen-3-one showed odor activity in the emulsions after 6 days of storage, for both pH 3 and 6. Larger amounts of odor active compounds were released from the pH 6 emulsion with extended storage. It was shown that this increased release at pH 6 was not due to increased volatility because an increase in pH diminished the static headspace concentrations of added compounds in emulsions.

Histatin 5 is a human basic salivary peptide with strong fungicidal properties in vitro. To elucidate the mechanism of action, the effect of histatin 5 on the viability of Candida albicans cells was studied in relation to its membrane perturbing properties. It was found that both the killing activity and the membrane perturbing activity, studied by the influx of a DNA-specific marker propidium iodide, were inhibited by high salt conditions and by metabolic inhibitors, like sodium azide. In addition, exposure to histatin 5 resulted in a loss of the mitochondrial transmembrane potential in situ, measured by the release of the potential-dependent distributional probe rhodamine 123. Localization studies using tetramethylrhodamine isothiocyanate-labeled histatin 5 or fluorescein isothiocyanate-labeled histatin 5 showed a granular intracellular distribution of the peptide, which co-localized with mitotracker orange, a permeant mitochondria-specific probe. Like the biological effects, uptake of labeled histatin 5 was inhibited by mitochondrial inhibitors and high salt conditions. Our data indicate that histatin 5 is internalized, and targets to the energized mitochondrion.

Two novel arabinofuranohydrolases (AXH-d3 and AXH-m23) were purified from Bifidobacterium adolescentis DSM 20083. Both enzymes were induced upon growth of Bi. adolescentis on xylose and arabinoxylan-derived oligosaccharides. They were only active with arabinoxylans and therefore denoted as arabinoxylan arabinofuranohydrolases. Their optimal activity was at pH 6 and 30–40 °C. They were very specific in their mode of action and were clearly different from AXH-m from Aspergillus awamori. AXH-m23 released only arabinosyl groups, which were linked to the C-2 or C-3 position of singly substituted xylose residues in arabinoxylan oligomers. AXH-d3 hydrolysed C-3-linked arabinofuranosyl residues of doubly substituted xylopyranosyl residues of arabinoxylans and arab- inoxylan-derived oligosaccharides. No activity was observed with C-2-linked arabinofuranosyl residues of these doubly substituted xylopyranosyl residues, or against C-2- and C-3-linked arabinofuranosyl residues of singly substituted xylopyranosyl residues. The combination of AXH-d3 and AXH-m showed low debranching activity with highly substituted glucurono-arabinoxylans. However, arabinoxylan from wheat flour was debranched almost completely.

In this work dynamic light scattering was used to study the thermal aggregation of patatin in situ, to elucidate the physical aggregation mechanism of the protein and to be able to relate the aggregation behavior to its structural properties. The dependence of the aggregation rates on the temperature and the ionic strength suggested a mechanism of slow coagulation, being both diffusion and chemically limited. The aggregation rate dependence on the protein concentration was in accordance with the mechanism proposed. The aggregation rates as obtained at temperatures ranging from 40 to 65 degrees C correlated well with unfolding of the protein at a secondary level. Small-angle neutron scattering and dynamic light scattering results were in good accordance; they revealed that native patatin has a cylindrical shape with a diameter and length of 5 and 9.8 nm, respectively.

Water-extractable arabinogalactan-peptides (WE-AGP) were isolated from flour of eight different wheat cultivars (harvest year 1996). Little structural variation in WE-AGP of flour of the different wheat cultivars was observed. The arabinose-to-galactose (A/G) ratio of WE-AGP varied between 0.66 and 0.73. Methylation analysis showed that the proportion of β-1,3-galactopyranosyl residues is almost equal for the different WE-AGP samples (10.2–11.1%). More variation was observed for the proportion of the β-1,6-galactopyranosyl residues (9.4–13.0%) and β-1,3,6-galactopyranosyl residues (76.0–80.1%). The 1H-nuclear magnetic resonance spectra (D2O, 85°C, 300 MHz) were comparable, and gel permeation analysis consistently yielded a narrow peak with an apparent molecular weight between 5.0 × 104 and 10.0 × 104. Interpretation of the results was facilitated by α-L-arabinofuranosidase debranching of WE-AGP. For flour samples of 18 wheat cultivars (10 from 1994 harvest, eight from 1996 harvest), the variation...

Alcohol insoluble solids from lemon albedo were extracted to obtain a chelating agent soluble pectin fraction (ChSS), a diluted sodium hydroxide soluble pectin fraction (ASS) which was separated into a water soluble and water insoluble part (ASSws and ASSwi), and an insoluble residue (Residue). ChSS, ASSws, ASSwi and Residue represented 64.3%, 10.4%, 0.4% and 8.1% of the galacturonic acid residues present in the lemon albedo, respectively. The pectin fractions and the residue were characterised by their sugar composition, degrees of methylation and acetylation, and molecular weight distribution. After extensive digestion with polygalacturonase and pectinesterase, the remaining high molecular weight fragments, representing the so-called pectic hairy regions (HR), were isolated and further characterised. After cold alkaline treatment (de-esterification), HR shown to be accessible to a further degradation by rhamnogalacturonan hydrolase (RGase) and the digests were analysed by high-performance size-exclusion chromatography (HPSEC) and high-performance anion-exchange chromatography (HPAEC). The various HR fractions differed in their degradation pattern: typically 2–4% of all glycosidic linkages were hydrolysed. The amount of RGase oligomers formed from the various fractions decreased in the order these were extracted while the degree of galactose substitution of the oligomers increased. Indications were found for the presence of small quantities of xylogalacturonan fragments within the pectic hairy regions of lemon albedo. On the basis of these results the structure of lemon pectin is compared with the structure of pectins extracted from other sources.

Cell wall material was isolated as water unextractable solids (WUS) from soybean meal. The isolation of WUS yields a fraction that contains 92% of the polysaccharides present in soybean meal and only a few other components. Arabinose, galactose, uronic acids and glucose (cellulose) were the major constituent sugars. WUS was sequentially extracted with chelating agent (chelating agent soluble solids, ChSS), dilute alkali (dilute alkali soluble solids, DASS), 1 m alkali (1 m alkali soluble solids, 1 m ASS) and 4 m alkali (4 m alkali soluble solids, 4 m ASS) to leave a cellulose-rich residue (RES). ChSS was the major extract, yielding 38% of the polysaccharides present in the WUS. All extracts and the residue were characterised by their sugar composition and their molecular-weight distribution. The extracts ChSS and DASS were fractionated by anion exchange chromatography. They showed identical elution patterns: an unbound fraction, five bound fractions of which one fraction eluted only with alkali. Anion exchange chromatography was also performed after saponification of both pectin-rich extracts, again resulting in identical elution patterns.

Gel filtration studies demonstrate that the heptameric complex of yeast cpn10 (pI around 8.8) reversibly disassembles into monomers when lowering the pH to 4.5, whereas its secondary structure is retained as demonstrated by circular dichroism. Monomeric yeast cpn10 does not bind to GroEL in the presence of nucleotides, whereas under identical conditionsE.colicpn10 (GroES), having a strong sequence homology to the yeast form but a pI of 5.2, shows no pH-dependent dissociation and is able to complex with GroEL at both pH 7.5 and 4.5. Using circular dichroism it is shown that, unlikeE.colicpn10, yeast cpn10 is not able to refold spontaneously after first being fully unfolded in 8 M urea. However, refolding of yeast cpn10 to a complex that can be recognised by GroEL depends on the presence of a lipid-water interface with a specificity for negatively charged lipids. We suggest that the requirements for refolding of yeast cpn10 are related to its post-translational transport and subcellular localization.

In our previous studies, the yeast Endomyces fibuliger LU677 was found to degrade amygdalin in bitter apricot seeds. The present investigation shows that E. fibuliger LU677 produces extracellular beta-glycosidase activity when grown in malt extract broth (MEB). Growth was very good at 25 degrees C and 30 degrees C and slightly less at 35 degrees C. When grown in MEB of pH 5 and pH 6 with addition of 0, 10 or 100 ppm amygdalin, E. fibuliger produced only slightly more biomass at pH 5, and was only slightly inhibited in the presence of amygdalin. Approximately, 60% of the added amygdalin was degraded (fastest at 35 degrees C) during an incubation period of 5 days. Supernatants of cultures grown at 25 degrees C and pH 6 for 5 days were tested for the effects of pH and temperature on activity (using amygdalin, linamarin and prunasin as substrates). Prunase activity had two pH optima (pH 4 and pH 6), amygdalase and linamarase only one each at pH 6 and pH 4-5 respectively. The linamarase activity evolved earlier than amygdalase (2 days and 4 days respectively). The data thus indicate the presence of at least two different glycosidases having different pH optima and kinetics of excretion. In the presence of amygdalin, lower glycosidase activities were generally produced. However, the amygdalin was degraded from the start of the growth, strongly indicating an uptake of amygdalin by the cells. The temperature optimum for all activities was at 40 degrees C. Activities of amygdalase (assayed at pH 4) and linamarase (at pH 6) evolving during the growth of E. fibuliger were generally higher in cultures grown at 25 degrees C and 30 degrees C. TLC analysis of amygdalin degradation products show a two-stage sequential mechanism as follows: (1) amygdalin to prunasin and (2) prunasin to cyanohydrin.

A method using immobilised yeasts has been developed and successfully applied for production of alcohol-free beer. The influence of environmental conditions present during alcohol-free beer production on the flocculation and immobilisation of the yeast Saccharomyces cerevisiae var. uvarum was investigated in the present study. In wort, the cells developed flocculation at the end of exponential growth, according to the NewFlo phenotype. In defined medium, the flocculation capacity appeared to be temporary and was lost rapidly during the stationary phase. No increase in cell wall hydrophobicity at the onset of flocculation was observed in either medium. Low growth temperatures increased flocculation capacity approximately four-fold, compared to growth at high temperatures. The optimum temperature for flocculation was at 25°C with cells grown at low or high temperature. A novel method using carboxyfluorescein-stained cells was developed to analyse the initial adhesion of cells to carrier. This method also allowed rapid analysis of the effects of immobilisation to DEAE-cellulose carrier during alcohol-free beer production process. It appeared that a high flocculation capacity stimulated adhesion to the DEAE-carrier.

Oligosaccharides derived from alkali-extracted sorghum glucuronoarabinoxylan by digestion with a combination of (1--4)-beta-D-arabinoxylan arabinofuranohydrolase (AXH) and endo-(1--4)-beta-D-xylanase (Xyl I), both from Aspergillus awamori, were purified by size-exclusion chromatography followed by preparative high-performance anion-exchange chromatography. Structural studies including monosaccharide analysis, methylation analysis, 1H NMR spectroscopy, and mass spectrometry were carried out, resulting in the characterisation of four novel oligosaccharides, namely, alpha-D-GlcpA-(1--2)-beta-D-Xyl p-(1--4)-beta-D-Xyl p-(1--4) -beta-D-Xyl p, alpha-D-GlcpA-(1--2)-beta-D-Xyl p-(1--4) [alpha-L-Araf-(1--3)]-beta-D-Xyl p-(1--4)-beta-D-Xyl p, alpha-D-GlcpA-(1--2)-beta-D- Xyl p-(1--4)-beta-D-Xyl p-(1--4)[alpha-L-Araf-(1--2)-alpha)-alpha- L-Araf-(1--3)]-beta-D-Xyl p-(1--4)-beta-D-Xyl p, and alpha-D-GlcpA-(1--2) -beta-D-Xyl p-(1--4)[alpha-L-Araf-(1--3] beta-D-Xyl p-(1--4)[alpha-L-Araf-(1--2)-alpha-L-Araf-(1--3)] -beta-D-Xyl p-(1--4)-beta-D-Xyl p. The various oligosaccharides identified provide additional insight into the structure of sorghum glucuronoarabinoxylan. Furthermore, novel data were generated with respect to the substrate specificity of AXH and Xyl I towards glucuronoarabinoxylans in general.

Aroma release from a cream style dressing, consisting of a thickening agent dispersed in the water phase of an oil in water (o/w) emulsion, has been studied by a purge-and-trap (PT) and a dynamic headspace mastication (DHM) model using two representative volatile compounds, viz. diacetyl and 2-heptanone. These isolations have been carried out from three systems: the dressing, the thickening agent dispersion and the o/w type of emulsion after adding different volumes of artificial saliva. Dilution of the samples with artificial saliva influences the amounts released for diacetyl and 2-heptanone differently: diacetyl decreases upon dilution of the thickening agent dispersion, emulsion and dressing. However, the amount of released 2-heptanone decreased only in the case of the thickening agent dispersion. These differences are caused by the distribution of diacetyl and 2-heptanone between the water and the oil phases. The distribution is not so important, when the DHM model is used for the release from dressings. The viscosity of the mixture of dressing and artificial saliva then plays an essential role. In general, the viscosity is considered to suppress the release of flavour. However, it has been found that the amount of volatile compounds released from the more viscous dressing was greater than from the emulsion. Most probably, the DHM model creates a large surface area by adhesion of the dressing on the wall of the sampling flask and the plunger head. This result suggests that the DHM equipment, which mimics the mouth movement, might be used to predict the real release of flavour in the mouth more precisely than other mouth models.

Maisbevattende voedingsmiddelen kunnen voor mensen met een glutenintolerantie ongunstig zijn omdat dit toxine een carcinogene werking heeft

The effect of toasting and extrusion at different shear levels on protein interactions in soybean meal was studied by extraction methods using buffers containing urea and dithiothreitol (DTT). It is suggested that noncovalent interactions were the main forces in protein structure formation during the toasting process but are less important during extrusion. After extrusion, both noncovalent interactions and disulfide bonds may be involved during low-shear extrusion. At higher shear levels, other covalent cross-linking reactions may also occur. After extrusion, mainly polypeptides of glycinin were found in the protein fractions obtained after extraction with DTT, especially the acidic polypeptide. In combination with in vitro protein digestibility results, it was concluded that glycinin is less digestible compared with β-conglycinin. It appeared that after toasting and especially after extrusion, an increasing amount of still active trypsin inhibitors could be detected after extraction with DTT, urea, and ...