豆蛋肉脯的品质影响因素初探

在传统肉脯的配方中添加了鸡蛋、豆粉及肥膘，研究了各因素对豆蛋肉脯品质的影响，并确定了较佳配方。     

Heating Conditions and Bread-Making Potential of Substandard Flour

ABSTRACT Heating weak bread flours (commercial cookie flour; commercial stone‐milled bread flour; Fundulea, a weak bread cultivar) at 80°C for 15 min had a positive effect on bread volume (P < 0.05). This positive effect was best seen when ascorbic acid was removed from bread formulation. Crumb springiness and fineness of grain, but not crumb hardness, were significantly improved after flour heating; cohesiveness improved with heated cookie flour (P < 0.05). After heating, flour a‐amylase content was lower; dough‐mixing stability of cookie flour doubled to 7.1 min but dropped from 18.0 to 4.8 min with standard bread flour. Heating offers possibility to upgrade substandard flour for bread‐making applications, especially in oxidant‐free dough system.     

The influence of oxidizing agents on water extracts of rye flour

The main constituents of rye flour extracts are proteins and pentosans. After cross-linking under the action of oxidizing agents those components are able to bind much more water than in their native (prior to modifications) state. As a consequence rheological properties of extract are changed.It was observed that kinematic viscosity of water extract of rye flour decreases rapidly with time. The reason for this behavior could be high enzymatic activity of flour extract.It was also found that the addition of hydrogen peroxide in the absence of additional peroxidase (which is naturally present in 1:9 or 1:1 water extracts of flour) causes the greatest increase in viscosity, due to the cross-linking of soluble polymers. Moreover after the addition of H₂O₂ to water extracts strong gels were obtained, which were characterized by tan δ = 0.5 (tan δ < 1). Moreover G′ was independent of frequency, which also suggests cross-linking of the pentosans.The addition of ascorbic acid, which is known to act preferably on gluten proteins, to 1:9 or 1:1 flour extracts had only a little effect on viscosity. In this case the values of tan δ = 0.9 were close to 1, which is typical for a weak gel.The application of inactivated rye flour extract, containing mainly proteins and pentosans, proved stronger effect of H₂O₂ in comparison to ascorbic acid on polymer cross-linking, but only after the addition of peroxidase. The gel obtained with H₂O₂ and peroxidase was also characterized by low tan δ = 0.4.The results indicate, that pentosans are the main subject of cross-linking reactions in rye flour water extracts.     

A bench-scale high-shear wet-milling test for wheat flour

Bench-scale wet-milling tests for wheat flour are available for the traditional processes of Martin and Batter, but tests for the high-shear processes of Alfa-Laval/Raisio, Hydrocyclone, and High-Pressure Disintegration are few in number. In this study, critical processing parameters of a high-shear wet-milling process, namely high-shear mixing, gluten-aging, and gluten-washing steps, were investigated using response surface methodology, and those parameters led to a bench-scale wet-milling test starting with a “highly sheared flour–water dispersion” (HS-FWD). Optimum conditions for the test were: a water–flour ratio (db) of 1.7, water temperature of 35 °C, and homogenizer speed of 6000 rpm for 2.0 min in the high-shear mixing step, a temperature of 40 °C for 20 min in the gluten-aging step, and gluten-washing of 2.0 min in the Glutomatic system. The HS-FWD wet-milling test with high level of repeatability was capable of discriminating wet-milling qualities of several hard, soft, and coarsely ground wheat flours.     

Comparison of properties of native and extruded amaranth (Amaranthus cruentus L. - BRS Alegria) flour

The aim of this study was to compare some of the properties of native and extruded amaranth flour obtained under mild and severe extrusion conditions. The chemical composition of the flours was similar. Flours obtained by both extrusion processes presented high solubility in water, low values of L∗ (luminosity) and an absence of endothermic peak on the DSC method. Water absorption, retrogradation tendency, final viscosity and the viscous behavior by rheology analysis were also studied. The results indicate that extruded flours have a good potential as an ingredient for food exposed to heat treatment at a high temperature and mechanical shear, for use in instant meal products. On the other hand, original flour properties are comparable to those of amaranth starch, which exhibits similarly high quality paste stability, low solubility in water, and elastic behavior, and could be used as a substitute for raw flour in a range of food formulas.     

Physicochemical property changes in germinated brown rice flour from different storage periods of paddy rice

This study revealed that the storage duration (2, 4, 6, 8, 10 and 12 months) of paddy rice and pH (3 and 6.8) of steeping water during germination were significantly influenced the physicochemical properties of germinated brown rice flour (GBRF). GBRF obtained at pH 3 vs. 6.8 provided the highest both reducing sugar content and free gamma‐aminobutyric acid (GABA) content (99.8 vs. 54.2 mg per 100 g flour respectively) as the paddy rice was stored for 8 months. The peak viscosity of GBRF obtained at pH 3 and 6.8 exhibited the lower values than that of non‐GBRF throughout the storage. From the principal component analysis, reducing sugar had a positive correlation with α‐amylase activity whereas a negative correlation was found with peak viscosity. GBRF from paddy rice stored for 8 months and germinated at pH 3 possessed the highest free GABA content, 50 times of the non‐GBRF, which can be further utilised in functional and healthy foods.     

Wheat-Legume Composite Flour Quality

Wheat-legume composite flours were produced by blending Canada Western Extra Strong (CWES) and Canada Western Red Spring (CWRS) wheat with varying amounts of three legume proteins. Legume protein addition produced breads with lower specific loaf volume, coarser crumb and firmer texture, and cooked white-salted noodles with greater compression stress and less cutting stress than the wheat controls. The CWES wheat compensated for the negative baking effects of the legume proteins as much as the CWRS wheat. End-use quality did not change at 2% soybean protein addition. Yellow pea protein produced the greatest quality changes, followed by chickpea and soybean protein.     

日处理小麦150 t脱皮制粉工艺改造设计

通过对日本佐竹生产的脱皮制粉设备在中国的应用，创出了适合中国国情的脱皮制粉新技术，从而解决了我国脱皮制粉技术存在的关键问题，实现了大中型面粉厂采用脱皮制粉技术生产专用粉的愿望，本篇重点介绍日处理小麦150t脱皮制粉生产线的改造设计．     

小麦粉流变学特性品质指标间的关系研究

采用粉质仪、拉伸仪、吹泡仪和面筋仪分别对56种具有代表性的小麦粉样品进行检测,研究小麦粉的粉质特性、拉伸特性、吹泡特性和面筋特性等流变学品质指标间的关系。结果表明:粉质特性、拉伸特性、吹泡特性和面筋特性有些指标之间存在显著或极显著相关关系,有些指标各自具有特异性。小麦和面粉进行品质检测时,应根据其检测目的和食品用途选择使用合适的指标进行评价,提高研究和检测效率。