An explanation for the combined effect of xylanase–glucose oxidase in dough systems

In the bakery industry, glucose oxidase is usually used in combination with xylanase. Although many theories exist on the mechanism of action of each enzyme, the positive effect of combining the two is as yet unexplained. In this paper we studied a possible basis for this synergy by focusing on the involvement of arabinoxylans. Water‐extractable arabinoxylans and water‐unextractable solids were studied in dough with or without glucose oxidase. Addition of glucose oxidase led to a stiffer and less extensible dough. Addition of arabinoxylans caused a further decrease in dough extensibility. Addition of xylanase could correct for this decrease. The role of arabinoxylans was further investigated by studying modified water‐extractable arabinoxylans and the effect of agents affecting arabinoxylan crosslinking (ferulic acid). Water‐extractable arabinoxylan was modified with xylanase to generate a low‐molecular‐weight fraction (WEAX_XYL). Alternatively, it was modified with NaOH to prepare a fraction with a decreased ferulic acid content (WEAX_OH). Addition of modified arabinoxylans diminished the effect of glucose oxidase. Glutenin macropolymer and water‐extractable arabinoxylan viscosity experiments were performed to obtain further detail on the role of arabinoxylans (AX). These results give rise to a new theory explaining the contribution of xylanase in its synergy with glucose oxidase. In this theory glucose oxidase not only catalyses the formation of protein disulfide bonds, but also of AX‐AX crosslinks. The latter negatively affect bread quality. Xylanase corrects for this latter effect by cleaving arabinoxylan complexes and generating small ferulic acid‐containing arabinoxylan fragments interfering with the crosslinking of high‐molecular weight arabinoxylans. Copyright © 2005 Society of Chemical Industry     

戊聚糖酶与氧化酶对面团流变性质影响的研究

研究了戊聚糖酶(Pentopan)、葡萄糖氧化酶(GOX)以及脂肪氧合酶(活性大豆粉,SF)对普通粉和专用粉面团流变性质的影响。由粉质曲线可知,不同品种的面粉,酶对面团吸水量的影响不同,对普通粉影响最大的是GOX;对专用粉影响最大的是Pentopan。由动态流变学试验知,Pentopan降低了面团中的弹性成分,GOX使弹性成分增加;GOX对普通粉的影响较大,SF则对专用粉的影响较大。     

外源戊聚糖酶对国产小麦面包粉品质的影响

通过流变学试验、面包烘焙试验和面包芯质构测试,探讨了戊聚糖酶对国产小麦面包粉品质的影响。试验表明,与对照组相比较,在添加适量戊聚糖酶后,面团的流变学性质、面包品质都得到明显改善。质构测试显示,戊聚糖酶可以有效地延缓面包制品的老化现象。试验条件下,添加戊聚糖酶60μg/g(酶/小麦粉)为最适添加量。     

The “Food Polymer Science” approach to the practice of industrial R&D,leading to patent estates based on fundamental starch science and technology

This article reviews the application of the “Food Polymer Science” approach to the practice of industrial R&D, leading to patent estates based on fundamental starch science and technology. The areas of patents and patented technologies reviewed here include: (a) soft-from-the-freezer ice creams and freezer-storage-stable frozen bread dough products, based on “cryostabilization technology” of frozen foods, utilizing commercial starch hydrolysis products (SHPs); (b) glassy-matrix encapsulation technology for flavors and other volatiles, based on structure-function relationships for commercial SHPs; (c) production of stabilized whole-grain wheat flours for biscuit products, based on the application of “solvent retention capacity” technology to develop flours with reduced damaged starch; (d) production of improved-quality, low-moisture cookies and crackers, based on pentosanase enzyme technology; (e) production of “baked-not-fried,” chip-like, starch-based snack products, based on the use of commercial modified-starch ingredients with selected functionality; (f) accelerated staling of a starch-based food product from baked bread crumb, based on the kinetics of starch retrogradation, treated as a crystallization process for a partially crystalline glassy polymer system; and (g) a process for producing an enzyme-resistant starch, for use as a reduced-calorie flour replacer in a wide range of grain-based food products, including cookies, extruded expanded snacks, and breakfast cereals.     

复合酶制剂对全麦馒头品质的改良作用

受加工技术水平影响,我国全谷物食品感官品质欠佳,产业发展缓慢。本研究采用生物酶对以纯全麦粉制作的馒头制品进行品质改良。结果表明:葡萄糖氧化酶(Gox)、戊聚糖酶(Pn)和纤维素酶(Ce)三酶协同作用,当添加量分别为Gox 40 mg/kg、Pn 40 mg/kg、Ce 30 mg/kg时,馒头比容可达到2. 69 cm~3/g,较空白样品提高22%;馒头高径比0. 56,挺立度适中;同时馒头内部结构明显改善,气孔均匀、质地疏松、富有弹性、粗糙感显著降低。     

戊聚糖与戊聚糖酶的协同作用对面团特性及面包烘焙品质的影响

从小麦麸皮中分别制备水溶戊聚糖和水不溶戊聚糖,然后将一定量的戊聚糖酶和水溶戊聚糖以及水不溶戊聚糖添加到面粉中,研究戊聚糖与戊聚糖酶的协同作用对面团特性及面包烘焙品质的影响.研究发现,戊聚糖酶和水溶戊聚糖一起添加到面粉中,可削弱水溶戊聚糖对面团特性及面包烘焙品质的改良效果,而戊聚糖酶和水不溶戊聚糖一起添加到面粉中,可削弱水不溶戊聚糖对面团特性及面包烘焙品质的弱化效果,对面团特性及面包烘焙品质有较好的改善效果.     

戊聚糖酶对小麦粉品质的影响研究

通过测试面筋乳酸溶液透光率和膨胀高度、水溶性阿拉伯木聚糖溶液黏度、可溶性戊聚糖量、粉质特性和面包烘焙品质,研究了戊聚糖酶对小麦面粉品质的影响;结果表明,戊聚糖酶的最适添加量为6g/100kg;在最适添加量下,随酶反应时间延长水溶性阿拉伯木聚糖溶液黏度下降,面粉中可溶性戊聚糖量增加;与对照组比较,添加适量的戊聚糖酶后,粉质特性和烘焙品质均有所改善。     

酶制剂及溴酸钾对面团流变学性质及显微结构的影响

本文研究了葡萄糖氧化酶、戊聚糖酶、脂肪酶和溴酸钾单独使用及复合使用时对面团流变学性质及面团内部显微结构的影响，分析了面团流变学性质和显微结构间的内在联系。同时，对在小麦粉品质改良中以酶制剂替代溴酸钾的可行性进行了简要讨论。     

Influence of Pentosanase and Oxidases on Water-extractable Pentosans during a Straight Breadmaking Process

ABSTRACT: Effects of flour type and enzymes on total pentosans (TP) and water‐soluble pentosans (WSP) and composition of isolated water‐extractable pentosans (WEP) during a straight breadmaking process were investigated. Two wheat flours (F1, F2) and 3 enzymes (pentosanase, glucose‐oxidase (GOX) and lacasse (LAC)), and their combinations were used. The presence of pentosanase increased the WSP content while oxidases produced a decrease. Extractability of pentosans was greater for dough than for bread but the latter had higher purity. Major sugars were xylose (Xyl) and arabinose (Ara) with a xylose/arabinose ratio between 1.00 and 1.56. Molecular weight profiles (MWP) of WEP comprised 5 fractions with the same distribution for the 2 flours but different relative proportions.