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。     

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。     

几种酶制剂对面包面团发酵体积的影响研究

探索了α-淀粉酶、戊聚糖酶、葡萄糖氧化酶对面团发酵体积的影响。实验结果表明,酶制剂对面包面团发酵体积具有较大的影响作用,随着α-淀粉酶、戊聚糖酶、葡萄糖氧化酶添加量的增加,面包面团发酵体积增加,当添加过量时,面包面团体积反而变小。最适酶制剂添加量是:α-淀粉酶添加量范围为0.5%~0.75%,戊聚糖酶添加量范围为1.0%~1.5%,葡萄糖氧化酶添加量范围为1%~1.25%。     

戊聚糖酶对大豆纤维面团粉质及面包焙烤品质影响研究

本文研究戊聚糖酶对含大豆纤维面团粉质及面包焙烤品质的影响。结果表明:戊聚糖酶 对大豆纤维面团流变学性质及面包焙烤品质有明显改良作用,并通过实验确定戊聚糖酶 适宜添加量。     

戊聚糖酶对面粉水溶物及面粉品质的影响（Ⅱ）

向软麦、中硬麦和硬麦各4种面粉中分别加入40 mg/kg戊聚糖酶,测定面粉水溶物组分、水溶物粘度和面粉品质变化,来探讨戊聚糖酶对面粉水溶物的影响。研究发现添加戊聚糖酶后面粉的水溶物含量、可溶性总糖和水溶性戊聚糖含量均有明显增加,加酶后面粉水溶物的相对黏度和增比黏度明显增大。对加酶后的面粉水溶物与水溶物黏度及面粉品质进行相关性分析可知,加酶后水溶物黏度与加酶后面粉水溶性戊聚糖呈极显著正相关,加酶后面粉的水溶物含量、可溶性总糖含量均与加酶后面粉峰值黏度、最低黏度、最终黏度、衰减值、回生值和峰值时间呈极显著负相关。     

戊聚糖酶对面粉水溶物组分及面粉品质的影响

通过对添加戊聚糖酶后面粉的基本指标和水溶物组分含量的测定,研究戊聚糖酶对面粉水溶物和面粉品质的影响。结果表明:加入戊聚糖酶后,面粉的湿面筋含量、峰值黏度、最低黏度和最终黏度均有不同程度的增加,面粉水溶物总量及水溶性戊聚糖的含量得到明显的提高;当戊聚糖酶添加量为40 mg/kg时,面筋含量、水溶物总量和水溶性戊聚糖含量达到最大值,制作的面包体积较大,感官评分最佳,能够明显地改善面粉及面制品品质。     

小麦麸皮及面粉戊聚糖对面团特性及面包烘焙品质影响的比较研究

从小麦麸皮和面粉中分别制备水溶和水不溶戊聚糖，将其以0．5％的比例添加到面粉中，以研究其对面团特性及面包烘焙品质的影响。研究发现，小麦麸皮水溶戊聚糖对面团特性及面包烘焙品质的影响与面粉中的水溶戊聚糖相似，可明显改善面团特性及面包烘焙品质，主要体现在：可增加面团的粉质吸水量，增加面团的稳定时间，增加面包的体积，改善面包的内部质构；小麦麸皮水不溶戊聚糖对面团特性及面包烘焙品质有明显的弱化作用；而面粉中的水不溶戊聚糖则对面团特性及面包烘焙品质影响不大。     

戊聚糖酶对南瓜面包品质的改良研究

研究了不同戊聚糖酶添加量对南瓜面包面团流变学特性、面包品质及面包老化的影响。结果表明,在戊聚糖酶添加量达60mg/kg时,南瓜面包面团的形成时间、稳定时间、评价值达到最大,弱化度最小;面粉的吸水率随戊聚糖酶添加量增大逐渐上升,但增幅较小。面团延伸性随戊聚糖酶添加量增大而逐渐增大,而面团的抗拉伸阻力、抗拉伸面积在戊聚糖酶添加量达60mg/kg时达到最大;拉力比数变化未呈现一定的规律性。面包比容及评分在戊聚糖酶添加量达60mg/kg时达到最大。戊聚糖酶在添加量达60、80mg/kg时,南瓜面包老化速率基本相同,均较缓慢。     

面筋生产废水中戊聚糖的提取及应用

从水洗小麦面筋废水中提取的水溶性戊聚糖，纯度较高，蛋白质含量较低。因微生物酶的作用，已产生了明显变性。在和面时加入戊聚糖可明显增加面团的吸水能力并减少和面时间。戊聚糖能降低淀粉的剪切强度并降低淀粉糊曲线的峰值粘度。添加戊聚糖对面包烘培性能产生有利影响，并且明显降低了室温贮存期内部面包芯的硬度。     

布拉迪酵母发酵对麦麸活性成分的影响

以小麦麸皮为原材料,通过布拉迪酵母发酵处理小麦麸皮降低植酸含量,提高可溶性戊聚糖(WEAX)和总酚含量以改善小麦麸皮的营养价值。研究固态发酵过程中小麦麸皮的基本组分与活性成分的变化,结果表明,经过发酵处理小麦麸皮的总膳食纤维(TDF)与不可溶性膳食纤维(IDF)含量显著提高,可溶性膳食纤维(SDF)含量提高但不显著;WEAX和总酚含量均呈现先增加后降低的趋势,最大分别增加了12.95倍、1.45倍;植酸含量显著降低,最大降解率为74.67%。     

Fractionation of crude pentosanase (arabinoxylanase) for improvement of the nutritional value of rye diets for broiler chickens

A pentosanase component of a crude enzyme product was concentrated and added to chick diets. Four levels of purity were examined: (a) the crude enzyme product, (b) a crude water extract, (c) a pentosanase purified using ion-exchange chromatography (non-bound fraction), and (d) residual pentosanase eluted with 0·4 M NaCl salt from the ion-exchange column (salt-eluted fraction). All preparations exhibited high viscosity-reduction capabilities when tested against a soluble pentosan preparation isolated from rye grain. The absence of arabinose release during rapid viscosity reduction of pentosan indicated that the non-bound pentosanase was an endoxylanase (1,4-β-D-xylan xylanohydrolase, EC 3.2.1.8) without α-L-arabino-furanosidase activity. When added to broiler chick diets containing rye as the only cereal, all enzyme preparations significantly improved growth and feed conversion. At equivalent viscosity-reduction activity the non-bound pentosanase was less effective than other preparations, suggesting that multiple enzymes may be necessary to elicit maximum benefit. Alternatively, since the non-bound enzyme was less pH stable it may have lost activity in the acidic environment of the foregut.     

A survey of water‐extractable arabinopolymers in bread and durum wheat and the effect of water‐extractable arabinoxylan on durum dough rheology and spaghetti cooking quality

BACKGROUND: Information on the variation in water‐extractable arabinopolymers (WEAP) in durum wheat and their impact on pasta quality is limited. A survey of the content of WEAP in selected bread wheat varieties and durum wheat was conducted and the influence of water‐extractable arabinoxylans (WEAX) on dough and spaghetti quality was examined by fortifying low‐WEAP durum semolina with purified WEAX. RESULTS: Bread wheat typically possessed higher levels of WEAP than durum wheat, but the latter had a greater range. Purified WEAX was extracted from bread wheat cultivar Sunlin which possessed a high level of WEAP. The extract was used to fortify semolina (0.125–2% w/w) derived from durum wheat variety Tamaroi (low WEAP). Fortification caused a near linear increase in farinograph water absorption of approximately 12% over the range of addition, leading to dough weakening. Reduced cooked pasta stickiness was observed at all levels of WEAX addition. CONCLUSION: Increased WEAX content may be a means to improve pasta quality by reducing pasta stickiness. Durum wheat showed a wide range of WEAP contents, and this may well be exploited by developing cultivars with elevated WEAP levels. © 2008 Crown in the Right of the State of New South Wales and Society of Chemical Industry.     

Functionality of enzymes that hydrolyse starch and non-starch polysaccharide in breadmaking

 Nine commercial enzyme preparations and two laboratory-designed mixes with amylase and/or pentosanase/xylanase activity were used to prepare bread samples, and the effects on bread quality and keeping properties were determined. With the doses added, enzymes significantly shortened fermentation time without affecting the pH or the machinability of the doughs. Bread with an improved volume, a greater intensity of aroma and a softer texture was obtained. Loaves had a less intense and characteristic taste and, in some cases, an uneven grain. All enzymes delayed bread firming, but rates varied with each preparation. Factor analysis classified bread samples according to their composition and source. Received:7 November 1996/Revised version: 21 January 1997     

Functionality of enzymes that hydrolyse starch and non-starch polysaccharide in breadmaking

 Nine commercial enzyme preparations and two laboratory-designed mixes with amylase and/or pentosanase/xylanase activity were used to prepare bread samples, and the effects on bread quality and keeping properties were determined. With the doses added, enzymes significantly shortened fermentation time without affecting the pH or the machinability of the doughs. Bread with an improved volume, a greater intensity of aroma and a softer texture was obtained. Loaves had a less intense and characteristic taste and, in some cases, an uneven grain. All enzymes delayed bread firming, but rates varied with each preparation. Factor analysis classified bread samples according to their composition and source. Received:7 November 1996/Revised version: 21 January 1997     

EFFECT OF PENTOSANASE ON DOUGH AND BREAD PROPERTIES PRODUCED BY DIFFERENT TYPES OF FLOURS

ABSTRACT

The effects of pentosanase at different doses (20, 60 and 100 ppm) on physical dough properties and bread quality were studied using three types of wheat flours. Flour A was a regular bread flour, flour B had a high hardness ratio and protein content, and flour C was prepared from the same blend of flour A but had a high extraction ratio. Regarding farinograph data, water absorption values of the high extraction (86%) flour C and high hardness (65%) blend flour B increased with introduction of pentosanase. Extensibility values of the flours increased moderately with pentosanase addition, while resistance and energy values decreased. The volume of breads made with flours C and B decreased upon addition of pentosanase. But loaf volume of breads prepared with regular bread flour A with 50% hardness and 76% extraction rate increased with high levels of pentosanase addition. In conclusion, flour A as a regular bread flour gave satisfactory results with pentosanase supplementations, whereas the harder‐blend (65%) and higher‐extraction‐rate (85%) flours from the same cultivars did not.

PRACTICAL APPLICATIONS

Pentosanase addition was more effective on soluble pentosans than on insoluble ones. Because of these effects, it enhanced the bread‐making properties of regular flour more effectively than those of the high‐extraction and harder‐blend flours of the same cultivars.

     

酶制剂在豆渣面包中的应用研究

通过烘焙实验,研究了添加豆渣粉、戊聚糖酶、脂肪酶、葡萄糖氧化酶对面包品质的影响。结果表明:酶制剂的加入,极大地改善了豆渣面包的品质,并使豆渣粉替代面粉的量由4%提高到8%以上;复合酶的效果好于单一酶,酶的复配比例与豆渣添加量有关。     

IMPROVEMENT OF THE WHEAT AND CORN BRAN BREAD QUALITY BY USING GLUCOSE OXIDASE AND HEXOSE OXIDASE

The effects of addition of wheat (10, 20 and 30%) and corn bran (10 and 20%) on rheological and bread making properties of flour were examined. To improve dough and bread properties, glucose oxidase (GO) and hexose oxidase (HO) (15–30 and 45 mg/kg) were used separately in each bran-wheat flour formula with L-ascorbic acid at 75 mg/kg, glucose at 0.5% and vital gluten at 9.2%. Water absorption and development time increased as the amount of wheat and corn bran increased, while dough stability, maximum resistance to extension, extensibility, energy and loaf volume decreased. Corn bran was found to be more detrimental to dough rheology and bread characteristics than wheat bran. Corn bran and wheat bran could be used at bread making up to levels of 10 and 20%, respectively. Addition of 30 mg/kg of HO in combination with constant additives was most effective in improving dough and bread characteristics and GO with its 15 mg/kg usage level followed it. Further increasing of enzyme levels led to over oxidizing of doughs and breads.

PRACTICAL APPLICATIONS

Corn bran up to 10% and wheat bran up to 20% levels can be used in bread making. To improve dough and bread quality, besides L-ascorbic acid (75 mg/kg) and vital gluten (as a percentage of added bran weight), GO (15 mg/kg) or HO (30 mg/kg) could be incorporated into wheat flour-bran mixtures. However, the amount of enzyme should be carefully chosen because when they are used above the mentioned levels, they cause overoxidation of doughs and small loaf volumes are obtained. As a conclusion; by using the corn bran, which is a by-product of the starch industry, not only could it be possible to offer healthy alternative breads which contain high amounts of dietary fiber to consumers, but it could also be possible to obtain economical value by evaluating such a by-product in the bread industry.     

重组脂肪氧合酶对面团流变性质及面包品质的影响

通过测定酶促作用前后面筋蛋白(wheat gluten,WG)的自由巯基含量、表面疏水性、黏弹性等的变化,研究了重组脂肪氧合酶(p ET-32a-ana-lipoxygenase,ana-r LOX)对水溶性阿拉伯木聚糖(water-soluble arabinoxylan,WEAX)和WG相互作用的影响,并探讨了ana-r LOX对面包品质改良的作用。结果表明,与添加WEAX的样品相比,加入ana-r LOX和WEAX后WG的自由巯基含量下降了21%,表面疏水性指数增大,流体动力学半径增大了27.3%,WG的黏弹性明显增加;面包的硬度、胶着性、咀嚼性降低,回复性增强,明显改善了面包品质。     

乳酸菌协同外源酶对全麦粉营养品质及抗氧化活性的影响

为了提高全麦粉营养品质,采用发酵和酶的协同作用探究对全麦粉品质的改善。通过对比短乳杆菌（Lactobacillus brevis,Lbr）和植物乳杆菌（Lactobacillus plantarum,Lac）和/或戊聚糖酶和纤维素酶（Cellulase/Pentosanase,Cel/Pn）处理发现二者在改善全麦粉时存在一定的协同关系。通过对不同发酵时间面粉基本组分的变化规律分析,发现Lbr具有更强的产酸能力。乳酸菌与酶协同处理对膳食纤维和戊聚糖影响显著,在发酵12 h后与Lac的总膳食纤维为11.09%,而Lac-Cel/Pn降低到9.71%,与Lbr相比,Lbr-Cel/Pn可溶性膳食纤维增加26.28%。Lac-Cel/Pn的水溶性戊聚糖含量比Lac增加56.19%。在Lac-Cel/Pn处理中植酸含量从2.97 mg/g降低到0.87 mg/g,植酸酶的活性增强,表明二者在降低植酸含量有显著的协同作用。通过对总酚含量和相应的抗氧化性分析表明,可检测到的游离酚含量通过12 h发酵,Lac的含量为99 mg/100 g,而Lac-Cel/Pn达到了116.9 mg/100 g,铁离子还原能力和DPPH清除能力也表明协同处理增强其抗氧化性更明显。综合结果表明乳酸菌协同酶作用显著改善全麦粉的品质。