慈姑全粉对曲奇饼干品质影响及配方研究

慈姑营养丰富,为提高其利用价值,将烘干所得慈姑全粉加入曲奇饼干中,讨论慈姑粉添加量对曲奇饼干品质特性的影响。结果表明,慈姑全粉的添加对饼干品质有明显的影响。在单因素试验基础上,以感官评分作为响应值,通过响应面法得到慈姑全粉曲奇饼干的最佳配方:低筋面粉100%,慈姑粉添加量25%,黄油添加量55%,鸡蛋添加量15%,糖粉添加量30%。     

Antioxidant potential of rice bran extracts and its effects on stabilisation of cookies under ambient storage

Methanolic extracts of rice bran (MRB) were found to be the richest in phenolics than all the other extraction media, i.e. water, 80% methanol, 70% ethanol, diethyl ether. Thermal stability of MRB was determined by evaluating antioxidant activity of heated extracts in linoleic acid system. Cookies were prepared in sunflower oil premixed with MRB at different concentrations, i.e. 500, 1000 and 2000 ppm, and with butylated hydroxytoluene and α‐tocopherol at 200 ppm. Oxidative stability of cookies was measured by storing under ambient conditions for an year with periodical analysis after every 2 months. Fatty acid composition was determined by gas–liquid chromatography. A regular decrease in unsaturated fatty acids (USFA) and increase in saturated fatty acids was observed with the increase in storage period; all the stabilised samples showed appreciably less decrease in USFA than that of control sample. Induction period ranged from 14.73 to 31.22 h while control exhibited 7.5 h. Peroxide value, iodine value and free fatty acids were chosen as the parameters for quality evaluation of cookies. Results suggest rice bran to be a potential source of antioxidants for stabilisation of cookies.     

Effects of ingredients and process conditions on 'Amaretti' cookies characteristics

This research aimed at determining the influence of different factors (i.e. ingredients and process conditions) on the most important characteristics defining consumers' appreciation of 'Amaretti' cookies using DOE (design of experiment) technique. A different recipe than the original one was used in the manufacturing of the cookies, where saccharose was partially replaced with fructose and bamboo fibre was added as a new ingredient. Besides fructose/saccharose ratio and fibre, the effect of egg white, baking time and baking temperature on quality responses (hardness, water activity, moisture content and colour) of 'Amaretti' was measured by using a fractional factorial design in a screening test. Responses were affected mostly by changes in temperature and fructose/saccharose ratio levels and then by baking time; bamboo fibre had a statistically significant influence only on hardness. The power of fit of the regression models was significant for all four responses and had R ² value in the range of 0.886–0.997. However, the power of prediction was significant only for hardness, moisture content and colour and had Q ² value in the range of 0.584–0.965. The mathematical model for water activity resulted inappropriate to explain the link between factors and response. The achieved results can represent a useful tool to address and facilitate the next phase of optimisation.     

Dietary plant materials reduce acrylamide formation in cookie and starch-based model systems

BACKGROUND: Dietary plant materials have attracted much attention because of their health benefits to humans. Acrylamide is found in various heated carbohydrate‐rich foods. Our previous results showed that crude aqueous extracts from diverse dietary plants and some phenolic compounds could mitigate acrylamide formation in an asparagine–glucose model system. Based on our previous study, several plant materials were selected to further investigate their inhibitory effects on acrylamide formation in cookies and starch‐based model systems. RESULTS: Addition of raw powders from selected dietary plants and their crude aqueous extracts could considerably reduce acrylamide formation in both cookie and potato starch‐based models. Aqueous extracts of clove at 4% caused the largest reduction (50.9%) of acrylamide in cookies, whereas addition of 2% proanthocyanidins from grape seeds gave the greatest acrylamide reduction (62.2%) in a starch‐based model system. CONCLUSION: It may be feasible to use some of the tested dietary plant materials to reduce acrylamide formation in cookies and other starchy foods. Copyright © 2011 Society of Chemical Industry     

天然抗氧化剂抑制曲奇中丙烯酰胺含量的研究

采用天然抗氧化剂荞麦、孜然和黑种草籽抑制曲奇中丙烯酰胺的生成。研究这3种配料对面粉中丙烯酰胺前体的含量、面粉和曲奇抗氧化的特性、曲奇烘焙特性和丙烯酰胺含量的影响,结果表明：这3种配料组合都可以增加面粉中还原糖和天门冬酰胺的含量,也可以增加面粉和曲奇的抗氧化特性(包括总酚类物质、DPPH自由基清除能力和ABTS+·的抑制能力)。当所添加的天然抗氧化剂含量增加时,曲奇颜色变深,表现为更低的L*,a*和b*值;荞麦和孜然的引入会增加曲奇中的水分含量,而黑种草籽则相反。所有天然抗氧化剂组合都可以增加曲奇的延展率。未添加天然抗氧化剂的曲奇中丙烯酰胺的含量为361.2μg/kg,而单独添加15%荞麦、15%孜然和15%黑种草籽使得曲奇中丙烯酰胺的含量分别降低了20.2%、67.6%和75.9%。感官分析结果表明：富含天然抗氧化剂的曲奇都可以被人们所喜欢。     

基于任务和角色的双重Web访问控制模型

互联网／内联网和相关技术的迅速发展为开发和使用基于Web的大规模分布式应用提供了前所未有的机遇,企业级用户对基于Web的应用(Web-based application,WBA)依赖程度越来越高．访问控制作为一种实现信息安全的有效措施,在WBA的安全中起着重要作用．但目前用来实现WBA安全的访问控制技术大多是基于单个用户管理的,不能很好地适应企业级用户的安全需求．因此提出了基于任务和角色的双重Web访问控制模型(task and role-based access control model for Web,TRBAC),它能够满足大规模应用环境的Web访问控制需求．并对如何在Web上实现TRBAC模型进行了探讨,提供了建议．同时,应用TRBAC模型实现了电子政务系统中网上公文流转系统的访问控制．     

网络数据库安全性问题及解决方法

对ASP开发网络数据库存在的漏洞进行分析，并提出了解决的方法。     

响应面法在豆纤维橙味曲奇饼干研制中的应用

本文以面粉、豆纤维粉、橙皮糖为主要原料,通过单因素实验,研究豆纤维粉添加量、橙皮糖添加量、糖油质量比(黄油与糖粉的比值)对豆纤维橙味曲奇饼干的感官评分和硬度的影响。按Box-Behnken法设计试验方案,运用响应面分析法建立多元二次非线性回归方程,以感官评分为指标,优化豆纤维橙味曲奇饼干配方,确定豆纤维粉添加量、橙皮糖添加量、糖油质量比。结果表明,豆纤维橙味曲奇饼干的最佳添加量为:豆纤维粉添加量为26%(以面粉与豆纤维粉的总量为基准)、橙皮糖添加量为16%、糖油质量比为2:1。在此条件下的曲奇饼干色泽均匀,硬度、甜度适中,并具有橙皮特有的清香以及豆纤维食品的独特口感,其感官评分为(87.3±1.1)分,与预测值87.7分接近,偏差为0.4%,说明该模型下确定的产品配方对实际生产具有较好的指导和应用价值。     

蒸汽爆破甘薯渣粉对小麦粉粉质及饼干品质特性的影响

研究蒸汽爆破甘薯渣粉对小麦粉粉质及混合粉制作饼干品质特性的影响。将蒸汽爆破甘薯渣粉添加到小麦粉中,测定不同比例蒸汽爆破甘薯渣粉与小麦粉混合后的沉淀指数、糊化特性、粉质特性以及混合粉饼干质构性质。结果表明：小麦粉中添加不同量的蒸汽爆破甘薯渣粉后,小麦混合粉的沉淀指数、峰值黏度、低谷黏度、稀懈值、最终黏度和反弹值均降低;蒸汽爆破甘薯渣粉添加到小麦粉中,面筋蛋白被稀释,吸水能力随可溶性膳食纤维质量分数的增加而增加,而面团的形成时间和稳定时间缩短,弱化度升高,粉质质量指数降低;混合粉焙烤出的饼干质构特性发生变化。根据饼干的质构特性和感官评定结果,在低筋面粉中添加质量分数6%的蒸汽爆破甘薯渣粉时,混合粉制作的饼干品质最佳。