Digestibility of gluten proteins is reduced by baking and enhanced by starch digestion.
Digestibility of gluten proteins is reduced by baking and enhanced by starch digestion.
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DOI：
10.1002/mnfr.201500262
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发表时间：
2015-10
影响因子：
5.2
通讯作者：
Mills EN
中科院分区：
文献类型：
--
作者：
Smith F;Pan X;Bellido V;Toole GA;Gates FK;Wickham MS;Shewry PR;Bakalis S;Padfield P;Mills EN
蛋白质对胃肠道消化的抵抗可能在确定免疫介导的食物不良反应中发挥作用。然而，消化研究主要局限于纯化蛋白质，食品加工和食品基质对蛋白质消化率的影响知之甚少。总麦醇溶蛋白组分（TGF），面粉（CV Hereward），和面包的消化率进行了评估，使用在体外分批消化模拟口腔，胃，和十二指肠阶段。通过SDS-PAGE和使用对腹腔毒性序列特异性的单克隆抗体（QQSF、QPFP）的免疫印迹监测蛋白质消化，并通过测量未消化的淀粉监测淀粉消化。而TGF在胃期被快速消化，面包中的面筋蛋白几乎不被消化，只有在包括淀粉酶的情况下才在十二指肠期被快速消化。在没有十二指肠蛋白酶的情况下，十二指肠淀粉消化也较慢。烘焙过程降低了小麦麸质蛋白的消化率，包括那些含有对乳糜泻有活性的序列的蛋白。淀粉消化影响蛋白质消化的程度，可能是因为在烘焙过程中形成了面筋-淀粉复合物。因此，单独使用纯化蛋白质级分的消化研究不能预测复杂食物基质的消化。
Resistance of proteins to gastrointestinal digestion may play a role in determining immune‐mediated adverse reactions to foods. However, digestion studies have largely been restricted to purified proteins and the impact of food processing and food matrices on protein digestibility is poorly understood. Digestibility of a total gliadin fraction (TGF), flour (cv Hereward), and bread was assessed using in vitro batch digestion with simulated oral, gastric, and duodenal phases. Protein digestion was monitored by SDS‐PAGE and immunoblotting using monoclonal antibodies specific for celiac‐toxic sequences (QQSF, QPFP) and starch digestion by measuring undigested starch. Whereas the TGF was rapidly digested during the gastric phase the gluten proteins in bread were virtually undigested and digested rapidly during the duodenal phase only if amylase was included. Duodenal starch digestion was also slower in the absence of duodenal proteases. The baking process reduces the digestibility of wheat gluten proteins, including those containing sequences active in celiac disease. Starch digestion affects the extent of protein digestion, probably because of gluten‐starch complex formation during baking. Digestion studies using purified protein fractions alone are therefore not predictive of digestion in complex food matrices.