Recent Progress and Recommendations on Celiac Disease From the Working Group on Prolamin Analysis and Toxicity
Scherf, Katharina A. ; Catassi, Carlo ; Chirdo, Fernando ; Ciclitira, Paul J. ; Feighery, Conleth ; Gianfrani, Carmen ; Koning, Frits ; Lundin, Knut E.A. ; Schuppan, Detlef ; Smulders, Marinus J.M. ; Tranquet, Olivier ; Troncone, Riccardo ; Koehler, Peter - \ 2020
Frontiers in Nutrition 7 (2020). - ISSN 2296-861X
barley - celiac disease - gluten - gluten-free diet - Prolamin Working Group - rye - wheat
Celiac disease (CD) affects a growing number of individuals worldwide. To elucidate the causes for this increase, future multidisciplinary collaboration is key to understanding the interactions between immunoreactive components in gluten-containing cereals and the human gastrointestinal tract and immune system and to devise strategies for CD prevention and treatment beyond the gluten-free diet. During the last meetings, the Working Group on Prolamin Analysis and Toxicity (Prolamin Working Group, PWG) discussed recent progress in the field together with key stakeholders from celiac disease societies, academia, industry and regulatory bodies. Based on the current state of knowledge, this perspective from the PWG members provides recommendations regarding clinical, analytical and legal aspects of CD. The selected key topics that require future multidisciplinary collaborative efforts in the clinical field are to collect robust data on the increasing prevalence of CD, to evaluate what is special about gluten-specific T cells, to study their kinetics and transcriptomics and to put some attention to the identification of the environmental agents that facilitate the breaking of tolerance to gluten. In the field of gluten analysis, the key topics are the precise assessment of gluten immunoreactive components in wheat, rye and barley to understand how these are affected by genetic and environmental factors, the comparison of different methods for compliance monitoring of gluten-free products and the development of improved reference materials for gluten analysis.
How Looking for Celiac-Safe Wheat Can Influence Its Technological Properties
Boukid, Fatma ; Mejri, Mondher ; Pellegrini, Nicoletta ; Sforza, S. ; Prandi, Barbara - \ 2017
Comprehensive Reviews in Food Science and Food Safety 16 (2017)5. - ISSN 1541-4337 - p. 797 - 807.
celiac disease - gluten - wheat quality - wheat safety - wheat technology
Because of the continuous increase in the prevalence of gluten-related disorders, selection of wheat with a low content of immunogenic gluten epitopes could be an innovative alternative for prevention. In this review, the focus is on literature data concerning the deallergenization tools of wheat, which are mainly related to breeding approaches (classic and advanced) and processing operations (germination and fermentation). Until now, no safe wheat genotype has been identified, whereas decreasing wheat allergenicity is possible. On the other hand, the decrease of gluten or some of its epitopes can strongly affect technological properties. Thus, obtaining celiac-safe gluten without affecting the technological properties of wheat could be considered as a new challenge that scientists will be facing. Celiac-safe wheat-based product development could be a great revolution in the market of foods for special medical purposes. The present paper is aiming to: (a) review the strategies and the approaches used, or that can be used, for developing low allergenic wheat: their utilities and limits were also discussed and (b) screen the impact of gluten reduction or removal on the quality of wheat end-use products.
Glutenvrij ? Pils onde de loep
Sleutels, I. ; Meer, I.M. van der; Broeck, H.C. van den - \ 2014
Voedingsmiddelentechnologie 7 (2014). - ISSN 0042-7934 - p. 10 - 11.
gluten - coeliakie - glutenvrije diëten - bieren - alcoholische dranken - gerst - lc-ms - analytische methoden - coeliac syndrome - gluten free diets - beers - alcoholic beverages - barley - liquid chromatography-mass spectrometry - analytical methods
Gluten meten in gehydrolyseerde en gefermenteerde voedingsmiddelen – zoals pils – is lastig. De door de Codex Alimentarius gevalideerde test onderschat het gehalte gluten in deze producten. Een uitgebreide LC-MS/MS-analyse geeft gedetailleerde informatie over de aanwezige coeliakie-stimulerende gluten in pils. Met deze gegevens is een geschikte test te ontwikkelen.
Phase segregation through transient network formation in a binary particle suspension in simple shear: Application to dough
Opheusden, J.H.J. van; Molenaar, J. - \ 2014
Physical Review. E, Statistical nonlinear, and soft matter physics 89 (2014). - ISSN 1539-3755 - 8 p.
brownian dynamics simulations - wheat doughs - flow - microstructure - gluten - deformation - separation - migration
In this paper we describe a viscoelastic type of phase separation in a simulated binary fluid with a sticky and an inert component, without any external gradients. Phase segregation under simple shear occurs due to transient network formation of the sticky component, expelling the inert particles from the network. When model parameters are adjusted to reduce network formation and rearrangement, the segregation effect is significantly smaller or absent. The behavior is independent of shear rate; segregation increases mainly with shear strain. The model is applied to wheat dough. Recent experiments have shown that prolonged shear flow of wheat dough can even give macroscopic segregation.
Enzyme-assisted separation and hydrolysis of gluten : options for intensification
Hardt, N.A. - \ 2014
Wageningen University. Promotor(en): Remko Boom, co-promotor(en): Atze Jan van der Goot. - Wageningen : Wageningen University - ISBN 9789462571228 - 165
gluten - graaneiwitten - scheiding - enzymen - hydrolyse - voedseltechniek - watergehalte - watergebruik - gluten - cereal proteins - separation - enzymes - hydrolysis - food engineering - water content - water use
The food industry is one of the largest water consumers in industry. Using large amounts of water, however, is undesirable from an environmental point of view because freshwater is a scarce good in many regions of the world and undesirable from an economic point of view because high water loadings require high amounts of energy for dehydration and signify high amounts of wastewater. This thesis uses wheat, one of the major crops in human nutrition, to study the influence of low water concentrations on two relevant processes in wheat processing:
The separation of starch and gluten. Separation is often performed using 10–15 L water per kg dry matter. Instead, starch and gluten can be separated by inducing shear using 0.5 L water per kg dry matter. In this thesis we make use of xylanases to hydrolyze arabinoxylan present in wheat, thereby releasing the water associated with arabinoxylan. In doing so, shear-induced starch–gluten separation is performed at even more concentrated conditions. The influence of arabinoxylan hydrolysis in wheat dough at low water contents is studied in chapters 2 and 3.The hydrolysis of gluten. Hydrolysis is currently performed using approximately 4 L water per kg dry mater. In this thesis we perform gluten hydrolysis at solid concentrations of up to 70%, thereby investigating the changes in the hydrolysis reaction and the functionality of the resulting hydrolysates. Wheat gluten hydrolysis at low water contents is studied in chapters 4, 5 and 6.
This thesis consists of seven chapters. Chapter 1 gives a general introduction of the thesis. In chapter 2, wheat dough rheology at low water contents below 40% and the influence of xylanases is studied. A reduction in water content from 43.5–44.8% (representing optimal Farinograph water absorption) to 34% (the lowest water content where a dough forms) results in a non-linear increase in the dough consistency, elastic modulus G’, and a decrease in the maximum creep compliance Jc,max of 1–2 orders of magnitude. Addition of xylanases has the same effect on the dough consistency, G’ and Jc,max as an increase in water content of 2–5% (on a water basis). Tan δ is hardly and Jel not influenced by xylanase addition showing that the influence of xylanases on the mechanism of hydration is negligible.
In chapter 3, shear-induced starch–gluten separation with the help of xylanases is studied at water contents from 43.5% to 34%. Addition of xylanases at the standard water content of 43.5% results in a slurry without any separation. As a result, lower water contents are used. At water contents below 40%, the local formation of gluten clusters is observed with and without xylanases addition. However, opposed to shear-induced separation at 43.5% water without xylanase, the gluten patches do not migrate to the center of the cone because of the densely packed dough and an inhomogeneity in the shear field. Nevertheless, gluten clusters can be concentrated up to 60% (N×5.7) protein. Similar to chapter 2, xylanase addition allows water savings of 3–5% (on a water basis).
Chapter 4 introduces enzymatic wheat gluten hydrolysis at high solid concentrations and describes the influence of high-solid hydrolysis on the resulting functional properties of the gluten hydrolysates. Wheat gluten can be hydrolyzed at solid concentrations of up to 60% (w/w). The water solubility of the dried hydrolysates is independent of the solid concentration during hydrolysis, just like the foam stabilizing properties at degrees of hydrolysis (DH%) below 8% At DH% above 8%, high solid concentrations even increase the foam stabilizing properties of the resulting hydrolysates, which is related to the presence of more peptides with a molecular mass >25 kDa. Furthermore, an increase in solid concentration results in an increase of the volumetric productivity.
Despite the advantages of high-solid gluten hydrolysis, we also observe lower hydrolysis rates in high-solid gluten hydrolysis compared to low-solid gluten hydrolysis at constant enzyme-to-substrate ratios. The factors causing this hydrolysis rate limitation are investigated in chapter 5. It is shown that enzyme inhibition, the water activity, and mass transfer limitations do not impede the hydrolysis up to 50% solids. However, the hydrolysis rate limitation can be explained by a second-order enzyme auto-inactivation rate along with the higher enzyme concentrations used. At solid concentrations above 50%, the hydrolysis rate further decreases due to mass transfer limitations. Furthermore, the addition of enzyme after 24 h at high solid concentrations hardly increases the DH%, suggesting that the maximum attainable DH% decreases at high solid concentrations. This DH% limitation is explained by a reduced enzyme activity due to a decline in water activity.
Based on the findings in chapters 4 and 5, a direct hydrolysis of gluten present in wheat flour at high solid concentrations is investigated in chapter 6, thereby omitting the starch–gluten separation. At a constant protein concentration, the protease activity is higher for wheat flour hydrolysis (at 40% total solids) than for vital wheat gluten hydrolysis (at 7.2% total solids) in the initial 6 h of hydrolysis, despite the high starch content in wheat flour and consequently lower water content. This is related to the starch granules in wheat flour, preventing the aggregation of (native) gluten. At wheat flour concentrations above 50% and for longer reaction times the positive effect of starch disappears. This is explained by mass transfer limitations and reduced water activities in the wheat flour slurry or dough, respectively.
Chapter 7 summarizes and generalizes the main findings of this thesis and compares the current status in starch–gluten separation and gluten hydrolysis with the concentrated separation and hydrolysis processes developed in this study. Water and energy savings of at least 50% are possible when separating and hydrolyzing at concentrated conditions. In the end, future prospects in high-solid wheat gluten hydrolysis are briefly discussed.
Analysis of electrostatic powder charging for fractionation of foods
Wang, J. ; Wit, M. de; Schutyser, M.A.I. ; Boom, R.M. - \ 2014
Innovative Food Science and Emerging Technologies 26 (2014). - ISSN 1466-8564 - p. 360 - 365.
polymer particles - glass-transition - metal plate - separations - electrification - solids - sorption - impacts - gluten - size
Electrostatic separation based on different tribo-electric charging behaviours of components has emerged as a novel, sustainable dry fractionation process. This study aims to characterise charging behaviour of single-component particles in nitrogen gas flowing through aluminium tubes. Experiments were carried out with polystyrene (PS) particles and wheat gluten as model particles. Results indicated that specific charge increased linearly with gas velocity up to 28 m/s for both materials. It was found that surface charge densities of different-sized PS particles overlapped for laminar gas flow, whereas for higher stronger gas flow rates, surface charge density of the smallest particles deviated from that of larger particles. Specific charge of PS particles increased linearly with increasing tube length from 125 to 225 mm. Additionally, charging of PS particles was unaffected by relative humidity (RH) of gas; however, specific charge of wheat gluten decreased for RH > 80%. Concluding, these results provide insight in critical parameters affecting charging behaviour, thus facilitating the development of electrostatic separation processes to fractionate food ingredients.
Glutamic acid production from wheat by-products using enzymatic and acid hydrolysis
Sari, Y.W. ; Alting, A.C. ; Floris, R. ; Sanders, J.P.M. ; Bruins, M.E. - \ 2014
Biomass and Bioenergy 67 (2014). - ISSN 0961-9534 - p. 451 - 459.
bio-based chemicals - amino-acids - protein - gluten - deamidation - biomass - solubility
Glutamic acid (Glu) has potential as feedstock for bulk chemicals production. It has also been listed as one of the top twelve chemicals derived from biomass. Large amounts of cheaper Glu can be made available by enabling its production from biomass by-products, such as wheat dried distillers grains with solubles (DDGS) derived from ethanol production. The aim of this study was to develop a new method for Glu production from biomass. Wheat gluten was used to represent wheat DDGS. To reduce chemicals usage, several methods were evaluated. These included enzymatic, dilute acid, and a combination of enzymatic and dilute acid hydrolysis. The separate enzymatic and dilute acid hydrolysis (1 M HCl; 95 °C) resulted in yields of 48% and 46% Glu, respectively. However, the combination of enzymatic and dilute acid hydrolysis resulted in a much higher yield of 70% Glu and 10% pyroglutamic acid thereby opening up new possibilities for the industrial production of Glu from biomass
Development of a standard test for dough-making properties of oat cultivars
Londono Cardona, D.M. ; Smulders, M.J.M. ; Visser, R.G.F. ; Gilissen, L.J.W.J. ; Hamer, R.J. - \ 2014
Journal of Cereal Science 59 (2014)1. - ISSN 0733-5210 - p. 56 - 61.
hydrostatic-pressure - celiac-disease - gluten - bread - quality - wheat - ultrastructure - batters
Bread is consumed all over the world. However, so far, production of large volume bread is only possible with wheat. Alternatives, such as oats, are less suitable but this is partly due to the lack of knowledge about their functionality for other purposes than porridge, which is their most common use. Existing standard tests for the dough making characteristics of wheat flour are not suitable for oat flour, hampering research to optimize oats for bread-making purposes. We therefore set out to develop a test to evaluate oat in relation to mixing and dough making properties using wheat as a model. It was possible to reproduce the profile of various qualities of wheat flour using mixtures of oat flour and gluten in different proportions. Our standard test was based on a dough system composed of 87.2% oat flour and 12.8% gluten and it presented similar properties to a wheat flour with regard to resistance to extension. This dough system was sensitive and reliable (coefficient of variation lower than 10%) for detecting differences among oat cultivars, and it can be used to screen oat varieties and individual oat components in relation to relevant properties for bread-making purposes.
Cracks in bread crust cause longer crispness retention
Hirte, A. ; Hamer, R.J. ; Hoffmann, L. ; Primo Martin, C. - \ 2013
Journal of Cereal Science 57 (2013)2. - ISSN 0733-5210 - p. 215 - 221.
making process - behavior - quality - starch - gluten - baking - crumb - state
Crispness is among the most important factors that the consumer uses to assess the quality of crispy bread. However, this quality attribute is rapidly lost after baking. It is known that crispness retention can be increased more than eight times by enhancing the water vapor permeability of the crust. Current methods to achieve this, i.e., puncturing the bread before baking, require an extra process step. We hypothesize that cracks that appear spontaneously on the crust surface after baking can also enhance water vapor permeability and therefore improve crispness retention. We were able to confirm this hypothesis by preparing composite breads containing the same crumb but different crusts, with crust recipes of varying starch/protein ratios. Crusts systems that were generally high in gelatinized starch content and poor in evenly distributed gluten were more prone to crack after the whole process of part-baking, freezing, and baking off. These cracks led to an increased water vapor permeability of the crust and an eight times longer instrumental crispness retention compared to standard bread. In this paper we also discuss possible causes for crack formation in the crust. We hypothesize that effective cracks are caused by thermal shock in materials with a low ability to dissipate energy.
Nanoweegschaal voor gluten
Beek, T.A. van - \ 2011
Kennis Online 8 (2011)dec. - p. 8 - 8.
voedseltechnologie - nanotechnologie - gluten - tests - gezondheid - allergenen - food technology - nanotechnology - gluten - tests - health - allergens
Wageningse chemici werken aan de ontwikkeling van een minuscule weegschaal op een chip. Mocht hij de verwachtingen waarmaken, dan kan de nanoweegschaal kleine hoeveelheden allergenen in voedsel meten, en misschien ook stoffen in het bloed die in een vroeg stadium auto-immuunziektes verraden.
Europese markt voor humane haver : haver, voedingsbron voor iedereen, inclusief Coeliakie patiënten?
Kamp, J.A.L.M. ; Reeuwijk, P. van - \ 2011
Lelystad : PPO AGV (PPO publicatie 416) - 38
avena sativa - haver - gluten - coeliakie - marketing - voedselindustrie - avena sativa - oats - gluten - coeliac syndrome - marketing - food industry
Haver uit een (gegarandeerd) glutenvrije keten blijkt wel veilig te zijn voor coeliakiepatiënten. Haver vormt tevens een goede aanvulling op het dieet van een coeliakiepatiënt, zowel qua smaak als qua voedingsstoffen. Dit wordt bekrachtigd door de gezondheidsclaim van de EFSA. De waarschuwingen van coeliakieverenigingen over de mogelijke besmetting van haver met gluten werkt echter negatief op de introductie van haver als glutenvrij alternatief. Gezien de positie van haver in het Verenigd Koninkrijk en de Scandinavische landen, ligt er ook in Nederland, Duitsland en Frankrijk een markt open voor glutenvrije haverproducten.
Naar een glutenvrije haverketen
Kamp, J.A.L.M. ; Reeuwijk, P. van - \ 2011
Lelystad : Praktijkonderzoek Plant & Omgeving, Business Unit Akkerbouw, Groene Ruimte en Vollegrondsgroenten (Publicatie / Praktijkonderzoek Plant & Omgeving nr. 409)
gluten - haver - markten - oppervlakte (areaal) - marktverkenningen - gluten - oats - markets - acreage - market surveys
project PPO 3250209111
Natural variation in avenin epitopes among oat varieties: implications for Celiac
Mujico, J.R. ; Mitea, C. ; Gilissen, L.J.W.J. ; Ru, A. ; Veelen, P. van; Smulders, M.J.M. ; Koning, F. de - \ 2011
Journal of Cereal Science 54 (2011)1. - ISSN 0733-5210 - p. 8 - 12.
t-cells - gliadin - gluten - wheat - peptides - prevalence - antibodies - toxicity - children - hla-dq2
Celiac disease (CD) is a chronic inflammatory disease affecting the small intestinal mucosa. The causative agents have been identified as gluten proteins from wheat, barley and rye, and the only available treatment for CD patients is a lifelong gluten-free diet. Non-gluten containing cereals would be a valuable contribution to the gluten-free diet. In this respect, oats are a good choice. However, commercial lots of oat flakes and flour frequently are contaminated with wheat, barley and rye, and two studies have reported that some peptides derived from the gluten-like avenin storage proteins of oat can trigger an immune response in some CD patients. In the present study we have initiated the investigation whether all oat varieties contain similar amounts of potentially harmful sequences by biochemical and immunological methods. We confirm that commercial oat preparations are contaminated with other cereals that contain gluten or gluten-like proteins. Moreover, our results demonstrate that contamination-free oat varieties differ in their capacity to stimulate an avenin-sensitive gamma-gliadin specific T cell line derived from a patient with CD, indicative for differences in the two known avenin epitopes among oat varieties, implying that selection and breeding of completely safe oat varieties for all CD patients may be a realistic possibility.
Evaluatie “Gezond met Haver” (IN-062)
PRI, ; PPO Akkerbouw, Groene Ruimte en Vollegrondsgroente, - \ 2010
avena sativa - haver - agro-industriële sector - gezondheidsvoedsel - gezondheidszorg - gluten - coeliakie - nieuwe voedingsmiddelen - voeding en gezondheid - avena sativa - oats - agroindustrial sector - health foods - health care - gluten - coeliac syndrome - novel foods - nutrition and health
In dit project was het de ambitie om een nieuwe verbinding te creëren tussen de agrosector en gezondheidssector om zo nieuwe producten en nieuwe product-markt te ontwikkelen. Het beoogde resultaat was een haverketen die hoogwaardige producten levert en die daarmee bij kan dragen aan de vermindering van enkele belangrijke maatschappelijke gezondheidsproblemen (coeliakie, obesitas, hart- en vaatziekten, diabetes, kanker). Dit project had tevens moeten leiden tot de ontwikkeling van een glutenvrije keten op basis van haver. Allergie voor gluten (coeliakie) vormt een toenemend gezondheidsprobleem. Haver vormt een goed alternatief voor mensen die allergisch zijn voor gluten.
Bread crispness and morphology can be controlled by proving conditions
Primo Martin, C. ; Dalen, G. van; Meinders, M.B.J. ; Don, A. ; Hamer, R.H. ; Vliet, T. van - \ 2010
Food Research International 43 (2010)1. - ISSN 0963-9969 - p. 207 - 217.
water activity - moisture migration - mechanical-properties - food-products - cereal foods - solid food - crust - gluten - crumb - redistribution
Bread crust crispness is lost when water migrates from crumb to crust during storage. To what extent water migration is influenced by morphology is not known. Therefore, the effect of crispy rolls morphology on crust crispness was studied. Crispy rolls were prepared at three proving volumes: 300 mL (short proving), 500 mL (control) and 800 mL (long proving). X-ray microtomography was used to characterize morphology. Water transport from crumb to crust was determined. Short proved crispy rolls showed lower rate of crust water uptake while longer proved rolls showed faster uptake during cooling down. Sensory analysis revealed higher crispness for short proved crispy rolls after the same storage time at low RH. We hypothesize that shorter proved crispy rolls with finer crumb morphology, more closed structure, smaller gas cells with less gas cells interconnections and a thicker crust have a significant positive effect on water uptake kinetics and crispness retention.
Relations between sensorial crispness and molecular mobility of model bread crust and its main components as measured by PTA, DSC and NMR
Nieuwenhuijzen, N.H. van; Tromp, R.H. ; Mitchell, J.R. ; Primo-Martin, C. ; Hamer, R.J. ; Vliet, T. van - \ 2010
Food Research International 43 (2010)1. - ISSN 0963-9969 - p. 342 - 349.
glass-transition temperature - wheat-starch - fracture-behavior - pulsed h-1-nmr - water-content - gluten - foods - state
Consumer appreciation of brittle cellular foods, like bread crusts, depends on textural properties such as crispness. This crispy character is lost above a certain water activity. It is not known what exactly is happening in these crusts when water enters. So is it unclear whether it is the change in the starch or the gluten that initiates the loss of crispness with ageing time. In this paper the effect of water on the glass transition of model bread crusts was studied using two complementary techniques: phase transition analysis (PTA) and temperature modulated differential scanning calorimetry (TMDSC). The mobility of water was studied with nuclear magnetic resonance (NMR). The results were compared with sensory data. Bread crusts prepared with different types of flour were tested to evaluate the effect of flour composition on the crispness of model crusts equilibrated at different relative humidities. In addition the single flour components starch and gluten were studied. Sensory crispness scores decreased with increasing aw from 0.55 upwards. At aw 0.70 sensory crispness was completely lost. Both DSC and PTA showed a transition point at an aw of 0.70-0.75. NMR gave a transition point in the mobility of the protons of water at aw 0.58. This supports the hypothesis that loss of crispness starts as a result of processes at a molecular level, before the macroscopic glass transition. This also suggests that the presence of water that is not directly attached to the solid matrix causes the loss of crispness at low aw. At higher aw increased mobility of the macromolecules will start to play a role. NMR experiments with the separate flour components indicate that the T2 transition point in starch samples occurs at a lower RH than for gluten. This could imply that starch loses crispness at lower aw than gluten. Increased mobility of small components and side chains might induce increased energy dissipation upon deformation of the material resulting in less available energy for fracture propagation and with that in a less crispy product.
Coeliakie, gluten en de ontwikkeling van granen met verlaagde toxiciteit
Gilissen, L.J.W.J. ; Meer, I.M. van der; Smulders, M.J.M. - \ 2009
Patient Care 12 (2009). - ISSN 0770-4224 - p. 19 - 23.
coeliakie - gluten - tarwegluten - graansoorten - toxiciteit - overgevoeligheid - eiwitten - voeding en gezondheid - voedselintolerantie - coeliac syndrome - gluten - wheat gluten - cereals - toxicity - hypersensitivity - proteins - nutrition and health - food intolerance
Coeliakie is een voedingsgerelateerd probleem, veroorzaakt door een overgevoeligheidsreactie op gluten. De diagnose is moeilijk te stellen wegens de grote verscheidenheid aan symptomen. Een levenslang glutenvrij dieet is tot op heden de enige remedie. Gluten is echter een product dat in toenemende mate in een breed scala aan voedingsmiddelen gebruikt wordt, waardoor het steeds moeilijker wordt om gluten te vermijden. Granen met een verlaagde coeliakietoxiciteit kunnen uitkomst bieden.
Sensory Crispness of Crispy Rolls: Effect of Formulation, Storage Conditions, an Water Distribution in the Crust.
Primo Martin, C. ; Vliet, T. van - \ 2009
Journal of Food Science 74 (2009)8. - ISSN 0022-1147 - p. S377 - S383.
breakfast cereals - fracture-behavior - bread crust - foods - texture - products - deformation - gluten - model
Crispness is an important sensory quality parameter that strongly influences the acceptability of cellular solid foods such as the crust of many types of breads. Crispness of the bread crust depends particularly on its water content. In this study, the relationship between sensory crispness of crispy rolls and the average water content of the crust was studied for different bread formulations (control, amylase, glucose-oxidase, and protease) and storage conditions (40% and 80% RH). From the different formulations used, only protease treatment increased the crispness of the crust and its retention at both storage conditions. The positive effect of the protease treatment was due to a lower water content of the crust of these breads compared to the other formulations. The relationship between sensory attributes, formulation, and storage conditions was found to be dominated by the dependence on storage conditions. When combining data for low and high humidity storage it showed that crusts with equal water contents could exhibit different scores for crispness. The results led to the hypothesis that a gradient of water content exists within the crust. At high humidity, the crust will take up water from both crumb and environment and a relative smaller gradient of water will exist within the crust. At low humidity on the other hand, the crust will take up water from the crumb only, resulting in a larger gradient of water within the crust.
Tetraploid and hexaploid wheat varieties reveal large differences in expression of alpha-gliadins from homoelogous Gli-loci
Salentijn, E.M.J. ; Goryunova, S.V. ; Bas, N. ; Meer, I.M. van der; Broeck, H.C. van den; Bastien, T.A. ; Gilissen, L.J.W.J. ; Smulders, M.J.M. - \ 2009
BMC Genomics 10 (2009). - ISSN 1471-2164 - p. 48 - 48.
single-nucleotide polymorphisms - celiac-disease patients - t-cell epitope - gene family - dna pools - protein - gluten - pyrosequencing(tm) - diversity - genomes
Background - A-gliadins form a multigene protein family encoded by multiple ¿-gliadin (Gli-2) genes at three genomic loci, Gli-A2, Gli-B2 and Gli-D2, respectively located on the homoeologous wheat chromosomes 6AS, 6BS, and 6DS. These proteins contain a number of important celiac disease (CD)-immunogenic domains. The ¿-gliadins expressed from the Gli-B2 locus harbour fewer conserved CD-epitopes than those from Gli-A2, whereas the Gli-D2 gliadins have the highest CD-immunogenic potential. In order to detect differences in the highly CD-immunogenic ¿-gliadin fraction we determined the relative expression level from the homoeologous Gli-2 loci in various tetraploid and hexaploid wheat genotypes by using a quantitative pyrosequencing method and by analyzing expressed sequence tag (EST) sequences. Results - We detected large differences in relative expression levels of ¿-gliadin genes from the three homoeologous loci among wheat genotypes, both as relative numbers of expressed sequence tag (EST) sequences from specific varieties and when using a quantitative pyrosequencing assay specific for Gli-A2 genes. The relative Gli-A2 expression level in a tetraploid durum wheat cultivar ('Probstdorfer Pandur') was 41%. In genotypes derived from landraces, the Gli-A2 frequency varied between 12% and 58%. In some advanced hexaploid bread wheat cultivars the genes from locus Gli-B2 were hardly expressed (e.g., less than 5% in 'Lavett') but in others they made up more than 40% (e.g., in 'Baldus'). Conclusion - Here, we have shown that large differences exist in relative expression levels of ¿-gliadins from the homoeologous Gli-2 loci among wheat genotypes. Since the homoelogous genes differ in the amount of conserved CD-epitopes, screening for differential expression from the homoeologous Gli-2 loci can be employed for the pre-selection of wheat varieties in the search for varieties with very low CD-immunogenic potential. Pyrosequencing is a method that can be employed for such a 'gene family-specific quantitative transcriptome profiling'
A food quality management research methodology integrating technological and managerial theories
Luning, P.A. ; Marcelis, W.J. - \ 2009
Trends in Food Science and Technology 20 (2009)1. - ISSN 0924-2244 - p. 35 - 44.
critical control point - hazard analysis - catering establishments - listeria-monocytogenes - safety - products - haccp - industry - gluten - chain
In this article it is argued how the complexity of food quality management combined with the high requirements on food quality requires a specific research methodology. It is concluded that food quality management research has to deal with two quite different paradigms, the one from technological and the other from managerial disciplines. Moreover, it must combine two types of research, i.e. managerial problem solving and fundamental scientific research. The research methodology is described as a stepwise process, wherein theory and practice are connected with a prominent place for selecting useful technological and managerial theories. This selection process is supported by a grid showing important topics in different research phases. The methodology is illustrated with a case example. Moreover, attention is paid to the role of the researcher in this type of interdisciplinary work, both as the intermediate between theory and practice and as the one to be critical towards theory-selection and use of data.