The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Severino S. Pandiella - One of the best experts on this subject based on the ideXlab platform.
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By-products of the rice processing obtained by controlled Debranning as substrates for the production of probiotic bacteria
Innovative Food Science & Emerging Technologies, 2019Co-Authors: Premsuda Saman, José Antonio Vázquez, Pablo Fuciños, Severino S. PandiellaAbstract:Abstract Cereal Debranning is a milling process in which bran layers are sequentially removed by controlled abrasion. Six rice fractions were produced with increasing Debranning degrees: A (0–2.3% w/w), B (2.3–3.8% w/w), C (3.8–5% w/w), D (5–6.3% w/w), E (6.3–7.3% w/w) and F (7.3–100% w/w). Fermentation media were prepared from all fractions, and evaluated for supporting the growth of two probiotic strains, Lactobacillus plantarum NCIMB 8826 and Lactobacillus reuteri NCIMB 8821. Biomass, substrate consumption, and lactic acid production were accurately modelled using an unstructured mathematical model. A 3.7% (w/w) Debranning degree resulted optimal in stimulating the growth of the selected probiotic strains. Results obtained suggest that this fraction might be suitable for producing potential synbiotic formulations. Industrial relevance There are many health benefits associated with the consumption of synbiotic foods, combining probiotic bacteria and prebiotic compounds. The development of rice-based synbiotic products might be an approach, offering a healthy alternative for individuals with, for instance, lactose intolerance.
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In vitro evaluation of prebiotic properties derived from rice bran obtained by Debranning technology
International journal of food sciences and nutrition, 2016Co-Authors: Premsuda Saman, José Antonio Vázquez, Kieran M. Tuohy, Glenn R. Gibson, Severino S. PandiellaAbstract:The prebiotic ability of several rice bran fractions obtained by Debranning (RBD) using human microbiota was studied in anaerobic batch cultures with agitation and pH-controlled. Fraction C (3.8–5% w/w pearling) from RBD increased the number of bifidobacteria and lactobacteria compared with the positive control, raftilose P95. RBD fermentation induced changes in the short-chain fatty acid (SCFA) profile. In addition, Fraction C revealed the highest growth of positive lactobacteria than commercial control. The present work illustrates the prebiotic capacity of RBD to modulate human microbiota and highlights that fraction C could be an economical source for use in human food as well as an interesting alternative to valorise a by-product of cereal industry.
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In vitro fermentation of oat bran obtained by Debranning with a mixed culture of human fecal bacteria.
Current microbiology, 2008Co-Authors: Gopal Kedia, Dimitris Charalampopoulos, José Antonio Vázquez, Severino S. PandiellaAbstract:The prebiotic potential of oat samples was investigated by in vitro shaker-flask anaerobic fermentations with human fecal cultures. The oat bran fraction was obtained by Debranning and was compared with other carbon sources such as whole oat flour, glucose, and fructo-oligosaccharide. The oat bran fraction showed a decrease in culturable anaerobes and clostridia and an increase in bifidobacteria and lactobacilli populations. A similar pattern was observed in fructo-oligosaccharide. Butyrate production was higher in oat bran compared to glucose and similar to that in fructo-oligosaccharide. Production of propionate was higher in the two oat media than in fructo-oligosaccharide and glucose, which can be used as energy source by the liver. This study suggests that the oat bran fraction obtained by Debranning is digested by the gut ecosystem and increases the population of beneficial bacteria in the indigenous gut microbiota. This medium also provides an energy source preferred by colonocytes when it is metabolized by the gut flora.
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Evaluation of the fermentability of oat fractions obtained by Debranning using lactic acid bacteria
Journal of applied microbiology, 2008Co-Authors: Gopal Kedia, José Antonio Vázquez, Severino S. PandiellaAbstract:Aims: The overall kinetics of the fermentation of four oat fractions obtained by Debranning using three potentially probiotic lactic acid bacteria were investigated. The main objective was to study the suitability of these fractions as fermentation media for the growth and the metabolic production of bacteria isolated from human intestine. Methods and Results: The cell growth, lactic acid production and substrate uptakes of the three lactobacilli was monitored for 30 h. An unstructured mathematical model was used to describe and fit the experimental data. In the medium from fraction B (1-3% pearlings or beta-glucan-rich fraction) all strains reached the highest cell populations, maximum growth rates and maximum lactic acid productions. This could be because of the high levels of total fibre and beta-glucan of this fraction. Limited growth and lactic acid formation was found in medium A (0-1% pearlings or bran-rich fraction). Conclusions: Medium B (1-3% pearling fraction) is the most suitable for fermentation and produces considerably higher probiotic cell concentrations. Significance and Impact of the Study: Debranning technology could be used to separate fractions from cereal grains for the production of functional formulations with higher probiotic levels than the ones that were obtained with the whole grain.
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Enzymatic digestion and in vitro fermentation of oat fractions by human lactobacillus strains
Enzyme and Microbial Technology, 2008Co-Authors: Gopal Kedia, José Antonio Vázquez, Severino S. PandiellaAbstract:Oats have received considerable interest for their high content of soluble and insoluble fibre and for their high fermentability with probiotic lactic acid bacteria. However, these fibres are not uniformly distributed within the oat kernel. Oat fractions were obtained by Debranning technology and the pearlings generated were hydrolysed in vitro using gastric and pancreatic enzymes of human origin. The indigestible part was separated using dialysis and the soluble and insoluble fibre was obtained by precipitation with ethanol. The suspensions were later fermented by lactic acid bacteria of human origin to evaluate the prebiotic potential of the oat fractions and flours in vitro. Of the three probiotic strains tested, Lactobacillus plantarum showed in all media a higher maximum growth. The 1-3% pearling oat sample has higher fermentation ability and the indigestible components of this fraction showed the highest growth of lactobacilli. Crown Copyright (c) 2008 Published by Elsevier Inc. All rights reserved.
Christophe M. Courtin - One of the best experts on this subject based on the ideXlab platform.
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Study of the intrinsic properties of wheat bran and pearlings obtained by sequential Debranning and their role in bran-enriched bread making
Journal of Cereal Science, 2016Co-Authors: Sami Hemdane, Jan A. Delcour, Niels A. Langenaeken, Pieter Jacobs, Joran Verspreet, Christophe M. CourtinAbstract:To gain insight in the causes of bread volume and crumb texture quality loss upon incorporation of wheat bran, the hydration properties, overall reducing compound levels and bran-associated enzyme activities of ground bran and bran pearling fractions were studied and related to their impact on bread making. Sequential pearling of wheat kernels to 3, 6, 9 and 12% by weight yielded pearling fractions P0–3%, P3–6%, P6–9% and P9–12%, strongly differing in hydration and (bio)chemical properties. Pericarp-rich fraction P0–3%, having the highest water binding and water retention capacity, showed the most adverse effects on bread volume and crumb texture, whereas addition of aleurone-rich fraction P6–9%, having low water binding and water retention capacities, showed less adverse effects on bread properties. P3–6% and P9–12% addition showed intermediate results, with a bread volume comparable to the control bread containing ground bran sample. Comparison of the effect of a heat treated versus a native fraction P0–3%, having a high bran-associated enzymatic activity, showed that bran-associated enzymes can clearly affect the Hagberg Falling Number of meal and bread crumb textural properties, but not bread volume. Overall, results suggest that bran hydration properties and enzymatic load affect the bread making potential.
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structure chemical composition and enzymatic activities of pearlings and bran obtained from pearled wheat triticum aestivum l by roller milling
Journal of Cereal Science, 2015Co-Authors: N De Brier, Jan A. Delcour, Sami Hemdane, Emmie Dornez, Sara Gomand, Christophe M. CourtinAbstract:Abstract While abrasive pearling (also referred to as Debranning) of wheat kernels prior to milling increases the quality of the resultant flour for producing bread, the potential applications of the co-products of pearling is largely unknown. We studied the impact of different degrees of pearling (0, 3, 6, 9 and 12% by weight) on the composition of pearlings and bran obtained when subsequently roller milling pearled wheat kernels. Pearling does not remove the kernel outer tissues homogeneously as abrasion affects especially the accessible parts of the kernels. Nevertheless, the first 3% removed consisted of mainly pericarp. With 6% or more removed, a significant amount of starchy endosperm ended up in the pearlings. The starting bran material and bran obtained by subsequent roller milling of pearled wheat kernels had similar compositions but the latter had a lower average particle size. Moreover, removal of the outermost kernel layers substantially decreased the enzyme activity levels in the bran.
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Debranning of wheat prior to milling reduces xylanase but not xylanase inhibitor activities in wholemeal and flour
Journal of Cereal Science, 2004Co-Authors: Wouter Gys, Christophe M. Courtin, Jens Frisbæk Sørensen, Kurt Gebruers, Jan A. DelcourAbstract:Debranning of wheat to remove the outer 7% of the kernel, prior to grinding or milling reduced xylanase activity in wheat wholemeal and wheat endosperm flour by up to 80 and 60%, respectively, whereas there was no significant reduction of xylanase inhibiting activity. Flours obtained after Debranning and milling showed no major differences in moisture content, whereas ash content decreased and protein and arabinoxylan content decreased slightly with increasing Debranning degree. Part of the xylanase activity in the flour was lost on addition of Triticum aestivum xylanase inhibitor (TAXI). Since TAXI specifically inhibits glycosyl hydrolase family 11 xylanases and since endogenous cereal xylanases belong exclusively to family 10, part of the xylanase activity in the flour is most likely of microbial origin. Debranning also significantly reduced alpha-amylase activities in wheat wholemeal and wheat flour. Debranning prior to milling can, therefore, impact on flour functionality.
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Reduction of xylanase activity in flour by Debranning retards syruping in refrigerated doughs
Journal of Cereal Science, 2004Co-Authors: Wouter Gys, Christophe M. Courtin, Jan A. DelcourAbstract:Doughs prepared from wheat flour by milling partially debranned grain with a 60% reduction of apparent xylanase activity levels compared with flours from whole kernels showed slowed solubilisation and degradation of arabinoxylans on refrigeration at 6 °C for up to 34 d. At the same time, dough syruping was effectively suppressed. The onset of syruping was delayed from 3 d to more than 16 d, and the rate of syrup development was slowed. In addition, the dough showed better retention of consistency. Loss of water-holding capacity due to degradation of arabinoxylans is considered to be one critical factor in the changed syruping behaviour of the refrigerated doughs.
Jan A. Delcour - One of the best experts on this subject based on the ideXlab platform.
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Study of the intrinsic properties of wheat bran and pearlings obtained by sequential Debranning and their role in bran-enriched bread making
Journal of Cereal Science, 2016Co-Authors: Sami Hemdane, Jan A. Delcour, Niels A. Langenaeken, Pieter Jacobs, Joran Verspreet, Christophe M. CourtinAbstract:To gain insight in the causes of bread volume and crumb texture quality loss upon incorporation of wheat bran, the hydration properties, overall reducing compound levels and bran-associated enzyme activities of ground bran and bran pearling fractions were studied and related to their impact on bread making. Sequential pearling of wheat kernels to 3, 6, 9 and 12% by weight yielded pearling fractions P0–3%, P3–6%, P6–9% and P9–12%, strongly differing in hydration and (bio)chemical properties. Pericarp-rich fraction P0–3%, having the highest water binding and water retention capacity, showed the most adverse effects on bread volume and crumb texture, whereas addition of aleurone-rich fraction P6–9%, having low water binding and water retention capacities, showed less adverse effects on bread properties. P3–6% and P9–12% addition showed intermediate results, with a bread volume comparable to the control bread containing ground bran sample. Comparison of the effect of a heat treated versus a native fraction P0–3%, having a high bran-associated enzymatic activity, showed that bran-associated enzymes can clearly affect the Hagberg Falling Number of meal and bread crumb textural properties, but not bread volume. Overall, results suggest that bran hydration properties and enzymatic load affect the bread making potential.
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structure chemical composition and enzymatic activities of pearlings and bran obtained from pearled wheat triticum aestivum l by roller milling
Journal of Cereal Science, 2015Co-Authors: N De Brier, Jan A. Delcour, Sami Hemdane, Emmie Dornez, Sara Gomand, Christophe M. CourtinAbstract:Abstract While abrasive pearling (also referred to as Debranning) of wheat kernels prior to milling increases the quality of the resultant flour for producing bread, the potential applications of the co-products of pearling is largely unknown. We studied the impact of different degrees of pearling (0, 3, 6, 9 and 12% by weight) on the composition of pearlings and bran obtained when subsequently roller milling pearled wheat kernels. Pearling does not remove the kernel outer tissues homogeneously as abrasion affects especially the accessible parts of the kernels. Nevertheless, the first 3% removed consisted of mainly pericarp. With 6% or more removed, a significant amount of starchy endosperm ended up in the pearlings. The starting bran material and bran obtained by subsequent roller milling of pearled wheat kernels had similar compositions but the latter had a lower average particle size. Moreover, removal of the outermost kernel layers substantially decreased the enzyme activity levels in the bran.
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Debranning of wheat prior to milling reduces xylanase but not xylanase inhibitor activities in wholemeal and flour
Journal of Cereal Science, 2004Co-Authors: Wouter Gys, Christophe M. Courtin, Jens Frisbæk Sørensen, Kurt Gebruers, Jan A. DelcourAbstract:Debranning of wheat to remove the outer 7% of the kernel, prior to grinding or milling reduced xylanase activity in wheat wholemeal and wheat endosperm flour by up to 80 and 60%, respectively, whereas there was no significant reduction of xylanase inhibiting activity. Flours obtained after Debranning and milling showed no major differences in moisture content, whereas ash content decreased and protein and arabinoxylan content decreased slightly with increasing Debranning degree. Part of the xylanase activity in the flour was lost on addition of Triticum aestivum xylanase inhibitor (TAXI). Since TAXI specifically inhibits glycosyl hydrolase family 11 xylanases and since endogenous cereal xylanases belong exclusively to family 10, part of the xylanase activity in the flour is most likely of microbial origin. Debranning also significantly reduced alpha-amylase activities in wheat wholemeal and wheat flour. Debranning prior to milling can, therefore, impact on flour functionality.
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Reduction of xylanase activity in flour by Debranning retards syruping in refrigerated doughs
Journal of Cereal Science, 2004Co-Authors: Wouter Gys, Christophe M. Courtin, Jan A. DelcourAbstract:Doughs prepared from wheat flour by milling partially debranned grain with a 60% reduction of apparent xylanase activity levels compared with flours from whole kernels showed slowed solubilisation and degradation of arabinoxylans on refrigeration at 6 °C for up to 34 d. At the same time, dough syruping was effectively suppressed. The onset of syruping was delayed from 3 d to more than 16 d, and the rate of syrup development was slowed. In addition, the dough showed better retention of consistency. Loss of water-holding capacity due to degradation of arabinoxylans is considered to be one critical factor in the changed syruping behaviour of the refrigerated doughs.
C. Webb - One of the best experts on this subject based on the ideXlab platform.
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Distribution of microbial contamination within cereal grains
Journal of Food Engineering, 2006Co-Authors: Adriana Laca, C. Webb, Z. Mousia, Mario Díaz, Severino S. PandiellaAbstract:Some of the microorganisms present in cereals constitute a potential problem since their development may alter the properties of the grains, and the mycotoxins produced by some moulds could potentially pose a health risk. It has been reported that these microorganisms are located close to the surface of the grain, but the real thickness affected by microbial contamination has not been determined. In this paper, the distribution of microorganisms present in wheat has been studied by controlled Debranning. An abrasive mill has been used to remove the outer layers of the wheat kernels and the process has been monitored by scanning electronic microscopy. The total mesophilic microorganisms and moulds contained in the pearlings have been measured. The contamination profiles obtained showed that in fact most of contamination was located close to the surface of the grain and the thickness affected has been estimated. Results show that by removing only some of the outer layers of the grains (pericarp) it is possible to substantially reduce the microbial contamination.
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Debranning technology to improve cereal-based foods
Using Cereal Science and Technology for the Benefit of Consumers, 2005Co-Authors: Severino S. Pandiella, Adriana Laca, Z. Mousia, Mario Díaz, C. WebbAbstract:ABSTRACT Debranning is a new technology that could benefit milling and cereal processing in general. The increasing number of industrial and scientific reports demonstrating the advantages of Debranning prior to milling has triggered a great deal of interest amongst the cereal processing community. Till recently the term bran included the aleurone layer since its separation from the outer bran layers is very difficult. This means that the aleurone cells are inevitably removed with the bran during traditional milling. Debranning gradually removes the outer layers from the surface of the cereal grain inwards. This means that the aleurone layer could remain attached to the endosperm. The Debranning process, although not a sophisticated technique, is becoming increasingly popular within the milling and baking industries because it can lead to better quality flour when compared to conventional milling. Flour refinement, measured by ash content and colour, is affected negatively by the milling yield. Several studies on the effect of bran on flour quality have shown that Debranning could improve flour refinement increasing its milling yield in parallel. Debranning also has led to the production of added-value by-products, which is a rapidly developing research area. Pearlings and debranned cereal kernels could also be used for the production of a number of novel food commodities like new types of bread and cereal-based fermented foods. In this paper, the composition, particle size distribution and structure of flour obtained using Debranning technology will be compared with conventional flour, and the results will be discussed.
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Effect of wheat pearling on flour quality
Food Research International, 2004Co-Authors: Z. Mousia, Severino S. Pandiella, Sarah Edherly, C. WebbAbstract:Debranning or cereal kernel pearling is increasingly recognised by the milling and baking industry as an important stage in cereal processing because it lowers the capital investment costs, giving as well, the benefit of better quality products. Pearling is the process, prior to milling that with the application of abrasion and friction removes effectively only the bran layers from the cereal grains, allowing nutritious parts, such as the aleurone layer to remain in the intact kernels. This pre-treatment potentially could also improve milling yields of superior flour quality. However, so far, there is no satisfactory explanation as to why pearled flour performs better than the unpearled. The effect of the wheat pearling prior to milling was investigated and the results showed that pearling affects flour quality characteristics. Using a laboratory scale Buhler mill, two samples of hard wheat were used, one with (pearled) and the other without the Debranning pre-treatment (unpearled) to test whether pearling affects flour milling and hence flour quality. It was found that the flour obtained from pearled wheat had differences from the unpearled wheat flour in the composition, structural properties; particle size distribution and starch damage and starch gelatinisation temperature.
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Application of cereals and cereal components in functional foods: a review.
International journal of food microbiology, 2002Co-Authors: Dimitris Charalampopoulos, Severino S. Pandiella, R. Wang, C. WebbAbstract:The food industry is directing new product development towards the area of functional foods and functional food ingredients due to consumers' demand for healthier foods. In this respect, probiotic dairy foods containing human-derived Lactobacillus and Bifidobacterium species and prebiotic food formulations containing ingredients that cannot be digested by the human host in the upper gastrointestinal tract and can selectively stimulate the growth of one or a limited number of colonic bacteria have been recently introduced into the market. The aim of these products is to affect beneficially the gut microbial composition and activities. Cereals offer another alternative for the production of functional foods. The multiple beneficial effects of cereals can be exploited in different ways leading to the design of novel cereal foods or cereal ingredients that can target specific populations. Cereals can be used as fermentable substrates for the growth of probiotic microorganisms. The main parameters that have to be considered are the composition and processing of the cereal grains, the substrate formulation, the growth capability and productivity of the starter culture, the stability of the probiotic strain during storage, the organoleptic properties and the nutritional value of the final product. Additionally, cereals can be used as sources of nondigestible carbohydrates that besides promoting several beneficial physiological effects can also selectively stimulate the growth of lactobacilli and bifidobacteria present in the colon and act as prebiotics. Cereals contain water-soluble fibre, such as beta-glucan and arabinoxylan, oilgosaccharides, such as galacto- and fructo-oligosaccharides and resistant starch, which have been suggested to fulfil the prebiotic concept. Separation of specific fractions of fibre from different cereal varieties or cereal by-products, according to the knowledge of fibre distribution in cereal grains, could be achieved through processing technologies, such as milling, sieving, and Debranning or pearling. Finally, cereal constituents, such as starch, can be used as encapsulation materials for probiotics in order to improve their stability during storage and enhance their viability during their passage through the adverse conditions of the gastrointestinal tract. It could be concluded that functional foods based on cereals is a challenging perspective, however, the development of new technologies of cereal processing that enhance their health potential and the acceptability of the food product are of primary importance.
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Application of cereals and cereal components in functional foods: a review.
International Journal of Food Microbiology, 2002Co-Authors: Dimitris Charalampopoulos, Severino S. Pandiella, R. Wang, C. WebbAbstract:The food industry is directing new product development towards the area of functional foods and functional food ingredients due to consumers' demand for healthier foods. In this respect, probiotic dairy foods containing human-derived Lactobacillus and Bifidobacterium species and prebiotic food formulations containing ingredients that cannot be digested by the human host in the upper gastrointestinal tract and can selectively stimulate the growth of one or a limited number of colonic bacteria have been recently introduced into the market. The aim of these products is to affect beneficially the gut microbial composition and activities. Cereals offer another alternative for the production of functional foods. The multiple beneficial effects of cereals can be exploited in different ways leading to the design of novel cereal foods or cereal ingredients that can target specific populations. Cereals can be used as fermentable substrates for the growth of probiotic microorganisms. The main parameters that have to be considered are the composition and processing of the cereal grains, the substrate formulation, the growth capability and productivity of the starter culture, the stability of the probiotic strain during storage, the organoleptic properties and the nutritional value of the final product. Additionally, cereals can be used as sources of nondigestible carbohydrates that besides promoting several beneficial physiological effects can also selectively stimulate the growth of lactobacilli and bifidobacteria present in the colon and act as prebiotics. Cereals contain water-soluble fibre, such as β-glucan and arabinoxylan, oilgosaccharides, such as galacto- and fructo-oligosaccharides and resistant starch, which have been suggested to fulfil the prebiotic concept. Separation of specific fractions of fibre from different cereal varieties or cereal by-products, according to the knowledge of fibre distribution in cereal grains, could be achieved through processing technologies, such as milling, sieving, and Debranning or pearling. Finally, cereal constituents, such as starch, can be used as encapsulation materials for probiotics in order to improve their stability during storage and enhance their viability during their passage through the adverse conditions of the gastrointestinal tract. It could be concluded that functional foods based on cereals is a challenging perspective, however, the development of new technologies of cereal processing that enhance their health potential and the acceptability of the food product are of primary importance.
Youna Hemery - One of the best experts on this subject based on the ideXlab platform.
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Distribution and composition of phytosterols and steryl ferulates in wheat grain and bran fractions
Journal of Cereal Science, 2012Co-Authors: Tanja Nurmi, Laura Nyström, Youna Hemery, Xavier Rouau, Anna-maija Lampi, Vieno PiironenAbstract:Abstract Phytosterols and steryl ferulates are bioactive compounds accumulating in the bran and germ of wheat. However, little is known regarding their localisation and composition in the bran layers of the kernel. The aim of this study was to determine the distribution of phytosterols and steryl ferulates in the wheat grain and in the different layers of bran. The wheat fractions, produced by conventional Debranning, aleurone separation and a novel electrostatic process, were analysed for phytosterol contents using GC–FID and for steryl ferulate contents using HPLC–UV. The compounds were identified by GC– and LC–MS. Phytosterols and steryl ferulates were concentrated in the bran layers. The steryl ferulates were accumulated in the intermediate layers, whereas the phytosterols were more evenly distributed in the intermediate layers and aleurone cell contents. The phytosterol composition varied within the wheat kernel, while the steryl ferulate composition was similar in different fractions. Sitosterol and campestanyl ferulate were the main compounds. The highest levels of phytosterols (up to 2117 μg/g) and steryl ferulates (up to 703 μg/g) were found in the pearling, aleurone and certain bran fractions. The phytosterol-rich fractions could be utilised in cereal foods to enhance the intake of health-promoting compounds from natural sources.
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Distribution and composition of phytosterols and steryl ferulates in wheat grain and bran fractions
Journal of Cereal Science, 2012Co-Authors: Tanja Nurmi, Laura Nyström, Youna Hemery, Xavier Rouau, Anna-maija Lampi, Vieno PiironenAbstract:Phytosterols and steryl ferulates are bioactive compounds accumulating in the bran and germ of wheat. However, little is known regarding their localisation and composition in the bran layers of the kernel. The aim of this study was to determine the distribution of phytosterols and steryl ferulates in the wheat grain and in the different layers of bran. The wheat fractions, produced by conventional Debranning, aleurone separation and a novel electrostatic process, were analysed for phytosterol contents using GC-FID and for steryl ferulate contents using HPLC-UV. The compounds were identified by GC- and LC-MS. Phytosterols and steryl ferulates were concentrated in the bran layers. The steryl ferulates were accumulated in the intermediate layers, whereas the phytosterols were more evenly distributed in the intermediate layers and aleurone cell contents. The phytosterol composition varied within the wheat kernel, while the steryl ferulate composition was similar in different fractions. Sitosterol and campestanyl ferulate were the main compounds. The highest levels of phytosterols (up to 2117 mu g/g) and steryl ferulates (up to 703 mu g) were found in the pearling, aleurone and certain bran fractions. The phytosterol-rich fractions could be utilised in cereal foods to enhance the intake of health-promoting compounds from natural sources. (c) 2012 Elsevier Ltd. All rights reserved.
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Grain fractionation revised for new healthy ingredients
2009Co-Authors: Xavier Rouau, Joel Abecassis, Youna Hemery, Cecile Barron, Marc Chaurand, Agnès Duri-bechemilh, Frederic Mabille, Milena Dos Reis Martelli, Abdelkrim Sadoudi, Marie-francoise SamsonAbstract:Cereal processes were long optimised for products containing only grain endosperm. So the milling technology has been improved over the centuries for the production of white flour or semolina as a major product exhibiting excellent functional and sanitary properties for second transformation. However, a large part of the bioactive compounds of the grain that are preferentially located in the outer layers is thus excluded from the mass cereal foods. The manufacture of whole grain products (or inclusion of whole bran in flours) constitutes a possible response to better exploit the grain nutritional potential but with some limitations. The breadmaking functionality of whole grain flours makes it difficult to manufacture diversified and appealing products for consumers. Also the outermost layers of the grains may contain some contaminants which are detrimental to the sanitary quality of the flours. At last, the bioactive compounds exhibit in general a poor availability as they are trapped in the cellular fibrous structures of the enveloppes. Revising the conventional grain fractionation processes in considering the properties and potential of all its different parts and tissues will aim at producing new healthy functional ingredients for cereal-based food products of high sensory quality. New tools designed to gain a better understanding of grain tissue structure and their behaviour upon processing are necessary to develop and optimize a new grain fractionation technology. For example, the combination of milling and Debranning monitored by a grain tissue marker methodology can allow to tailor flours with different levels of peripheral layers inclusion, quantitatively and qualitatively. The by-products from the milling industry (brans) can be exploited also as a source of healthy ingredients. They can undergo different cracking diagrams using advanced technologies of grinding and separation, to result in concentrates of grain tissues or sub-fractions of contrasted functional properties with improved availability of bioactives.
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Biochemical markers: Efficient tools for the assessment of wheat grain tissue proportions in milling fractions
Journal of Cereal Science, 2009Co-Authors: Youna Hemery, Joel Abecassis, Per Aman, Valérie Lullien-pellerin, Xavier Rouau, Marie-francoise Samson, Walter Von Reding, Cäcilia Spoerndli, C. BarronAbstract:To produce safe and healthy whole wheat food products, various grain or bran dry fractionation processes have been developed recently. In order to control the quality of the products and to adapt these processes, it is important to be able to monitor the grain tissue proportions in the different milling fractions produced. Accordingly, a quantitative method based on biochemical markers has been developed for the assessment of grain tissue proportions in grain fractions. Grain tissues that were quantified were the outer pericarp, an intermediate layer (including the outer pericarp, the testa and the hyaline layer), the aleurone cell walls, the aleurone cell contents, the endosperm and the germ, for two grain cultivars (Tiger and Crousty). Grain tissues were dissected by hand and analysed. Biochemical markers chosen were ferulic acid trimer, alkylresorcinols, para-coumaric acid, phytic acid, starch and wheat germ agglutinin, for outer pericarp, intermediate layer, aleurone cell walls, aleurone cell contents, endosperm and germ respectively. The results of tissue quantification by hand dissection and by calculation were compared and the sensitivity of the method was regarded as good (mean relative errors of 4% and 8% for Crousty and Tiger outer layers respectively). The impact of the analytical variability (maximum 13% relative error on coarse bran) was also regarded as acceptable. Wheat germ agglutinin seems to be a promising marker of wheat germ: even if the quantification method was not able to quantify the germ proportions in milling fractions, it was able to classify these fractions according to their germ content. The efficiency of this method was tested, by assessing the grain tissue proportions of fractions exhibiting very different compositions such as flour, bran and aleurone-rich fractions obtained from three different grain or bran dry fractionation processes (conventional milling, Debranning process, production of aleurone-rich fractions from coarse bran). By calculation of the composition of the different products generated, it was possible to study the distribution of the different tissues among fractions resulting from the different fractionation processes. This quantitative method is thus a useful tool for the monitoring and improvement of processes, and allows the effects of these processes to be understood and their adaption to reach the objectives.
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Dry processes to develop wheat fractions and products with enhanced nutritional quality
Journal of Cereal Science, 2007Co-Authors: Youna Hemery, Valérie Lullien-pellerin, Xavier Rouau, Cecile Barron, Joel AbecassisAbstract:Numerous epidemiological studies have investigated the potential health benefits of consuming more wholegrain foods. However, in Europe, most wheat-based food products are made with refined endosperm from which the germ and peripheral layers (bran) are excluded, although these tissues have considerable nutritional potential and contain most of the micronutrients, phytochemicals and fibre of the grain. Dry fractionation technologies allow these peripheral tissues to be separated and recovered to efficiently separate valuable from detrimental components (i.e. contaminants, antinutrient compounds, irritants), in order to develop nutritionally enhanced ingredients and products. The rational development of efficient processes requires the ability to monitor the fractionation and understand the fate of grain tissues, and to take into account the various properties of the different parts of the grain in order to design an appropriate fractionation protocol. This review provides an overview of the existing processes that can be used for the production of wheat products and fractions with enhanced nutritional interest. The grain composition and properties are briefly introduced with emphasis on nutritionally interesting compounds. Tissue markers and their application in process monitoring are presented, and the physical properties that influence the fractionation properties of grain tissues are developed. The main wheat dry fractionation processes are then reviewed, including pretreatments, degerming, Debranning, and bran fractionation
