红薯全粉粉丝的配方优化

为提高粉丝的营养价值，拓宽红薯资源在食品中的应用。本研究以红薯全粉和玉米淀粉为原料，以粉丝的烹煮品质和质构特性为指标，在单因素试验的基础上进行正交试验，对红薯全粉粉丝的配方进行优化。本试验在固定红薯全粉和玉米淀粉复配比例为1∶1的基础上，考察水添加量、碳酸钠及复合磷酸盐用量对红薯全粉粉丝烹煮品质和质构特性的影响。结果表明，红薯全粉粉丝最佳配方参数为：水添加量98%、碳酸钠用量0.5%和复合磷酸盐用量0.4%，此配方制作的红薯全粉粉丝断条率仅为3.33%±2.88%。利用最佳配方制作的红薯全粉粉丝爽滑劲道，具有独特的生红薯的清香。     

无矾红薯粉丝品质改进

甘薯淀粉不溶性直链淀粉含量较低(14%),使得其制得的粉丝有易断条糊汤的问题。因此在以甘薯淀粉为主要原料生产粉丝的过程中,经常加入明矾(十二水合硫酸铝钾)以增加其韧性和耐煮性。以90%甘薯淀粉+10%木薯淀粉为主要原料,选择羟丙基二淀粉磷酸酯、蜡质马铃薯淀粉、沙蒿胶为明矾替代物。通过单因素实验和正交实验测定混合粉的RVA参数;采用物性仪测定粉丝的拉伸性;并进行感官评价和短条率分析,研究发现原料粉中加入羟丙基二淀粉磷酸酯(5%)、蜡质马铃薯淀粉(3%)、沙蒿胶(0.50%),可明显提高红薯粉丝的品质,显著改善其断条糊汤状况,使无矾红薯粉丝在感官评价中可接受性显著提高。     

交联淀粉性能与鲜粉丝耐煮性关系

本文以马铃薯淀粉、红薯淀粉和木薯淀粉为原料,三氯氧磷为交联剂,氯化钠为膨胀抑制剂,制备了不同交联度的交联淀粉,研究了交联对薯类淀粉性能及鲜粉丝耐煮性的影响。采用断条率、吸水率表征鲜粉丝的耐煮性,采用沉降积法测定淀粉的交联度。结果表明:交联淀粉用量和交联度对鲜粉丝耐煮性均有影响。淀粉经交联后,其蓝值、膨胀能力降低,但其冻融稳定性增加。     

增稠剂对山药-豌豆粉丝感官品质和烹煮特性的影响

以无架双胞山药全粉和豌豆淀粉为原料制作复合粉丝,研究黄原胶和海藻酸钠2种增稠剂及其用量对粉丝感官品质和烹煮特性的影响。结果发现,与无增稠剂的对照相比,黄原胶和海藻酸钠均显著提高粉丝感官品质,且黄原胶比海藻酸钠更能提高粉丝感官品质、烹煮前后的粗度差及熟煮损失。黄原胶和海藻酸钠添加量分别为0.2%和0.4%时,粉丝的感官品质最高,断条率、膨胀系数和糊汤度最低,且有适宜的硬度。因此,黄原胶和海藻酸钠的加入显著改善无架双胞山药-豌豆复合粉丝的感官品质和烹煮特性,且黄原胶比海藻酸钠更能提高粉丝感官品质,但对淀粉原料的黏结程度弱于海藻酸钠。0.2%黄原胶或0.4%海藻酸钠为适宜添加量,用其制作出的粉丝感官品质和耐煮性均达到最佳。     

马铃薯全粉添加量对挂面品质的影响

研究马铃薯全粉在小麦粉中添加量对制作挂面的品质影响。分析马铃薯全粉混合粉的理化特性和粉质特征,挂面的蒸煮品质、质构品质和感官评价。随着马铃薯全粉添加量增加,混合粉的粗蛋白和湿面筋降低,粗淀粉增加,粉质质量指数下降。添加量为15%的挂面蒸煮损失最小,吸水率和水分含量最低,而其拉伸强度和最大弯曲力最高,硬度、弹性和咀嚼性均处于中等偏上水平,结合感官评价认为马铃薯全粉添加15%时,挂面品质较好。     

普鲁兰酶酶解处理红薯淀粉及其性质研究

以红薯淀粉为研究对象,分析普鲁兰酶酶解处理对红薯淀粉性质的影响。结果显示采用普鲁兰酶酶解脱支处理后,红薯直链淀粉质量分数增加了8.57%。对酶解前后淀粉的理化性质、微观颗粒形态、糊化和老化特性以及凝胶特性等进行分析比较,发现酶解后淀粉颗粒表面出现空穴,呈现出不规则的多边形,增加了反应位点;酶解后淀粉溶解度、膨润力降低,淀粉颗粒内部键结合力增强,透光率增加显著,凝沉性增强;酶解后淀粉糊化特性和凝胶特性发生变化,淀粉稳定性增强,高温下耐剪切力增强,硬度增大;淀粉热力学性质:起始糊化温度由63.70℃增加到71.75℃、峰值糊化温度由72.35℃增加到76.20℃、终止糊化温度和糊化焓都升高;还发现酶解后淀粉老化度有增加。粉丝品质会受到原料直链淀粉含量的影响,酶解红薯淀粉在提升红薯粉丝品质方面具有应用前景。     

蚕豆和高直链玉米淀粉对马铃薯粉条品质的影响

为研究蚕豆淀粉和高直链玉米淀粉对马铃薯粉条的影响,分别将蚕豆淀粉、高直链玉米淀粉以及两者的混合粉与马铃薯淀粉进行不同比例混合,探讨了共混体系的理化特性并分析了粉条的品质。结果表明,加入蚕豆和高直链玉米淀粉及混合粉均可以降低混合体系的膨胀度、溶解度,提高凝胶的色泽、硬度、凝胶强度、最大破断力;加入蚕豆和高直链玉米淀粉及混合粉显著降低了粉条的断条率、膨润度及蒸煮损失,增强了粉条的硬度、内聚性、回复性、剪切强度和拉伸强度;在所有指标中,添加蚕豆和高直链玉米淀粉混合粉的变化最明显,在添加量为20%时感官评分最高。     

玉米淀粉/酪蛋白复合物凝胶的质构特性和结构研究

系统考察了不同比例的玉米淀粉/酪蛋白的凝胶质构特性,并利用差示扫描量热和激光拉曼光谱技术对玉米淀粉与酪蛋白复合物的热力学性质和分子结构的变化进行了研究.结果表明,玉米淀粉/酪蛋白凝胶的硬度、黏附性、胶黏性、咀嚼性与玉米淀粉和酪蛋白之间的比例密切相关,在酪蛋白含量占固形物比例为40.0％～50％时其凝胶质构性能发生较大变...     

玉米全粉对方便米线原料粉浆流变特性的影响

为了考察玉米全粉的添加对方便米线原料粉凝胶及流变特性的影响,以四种大米混合为原料,通过添加21%、23%、25%、27%、29%等五种不同含量的玉米全粉,研究其混合体系的流变学特性。结果表明,玉米全粉和方便米线原料大米混合粉浆凝胶体系随着玉米全粉添加量的增大,流体的假塑性不断增强,剪切稀化的现象越明显;当其添加量大于23%时,混合粉浆凝胶的黏稠度逐渐减小,流动性增强,体系开始形成的新的网络结构逐渐趋于稳定;23%和29%添加量体系的G＇明显高于其他添加量,未添加的体系G″对频率依赖性大于已添加玉米全粉的混合粉浆,而体系G＇对频率的依赖性却不受添加量的影响。     

食品中RS3含量与凝胶性的关系

测定了米线、粉丝、馒头、面包和红薯淀粉中RS3的含量,比较RS3含量与凝胶性的关系.米线中RS3为9.882%,绿豆粉丝为7.902%,水晶粉丝为10.449%,红薯粉丝为10.899%.在冷藏过程中,馒头和面包样品随着RS,含量的增加,凝胶的硬度分别从1031.45g和349.87g增加到4820.10g和851,45g,弹性分别从0.96和0.923下降到0.858和0.9075.红薯淀粉随着加热-冷却处理次数的增加,RS3含量从2.55%增加到6.95%,凝胶的硬度从82.198g增加到497.461g,弹性从0.988下降到0.923.因此,随着RS3含量的增加,凝胶的硬度均显著增加,而弹性变化不大.     

Probiotics and prebiotics--perspectives and challenges

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.     

常用消毒灭菌法及其机理与应用

介绍了采用消毒灭菌方法,有加热消毒法,紫外线辐射法和化学药剂消毒法。常用化学药剂有醛类、含氯消毒剂、醇类消毒剂以及高锰酸钾、生石灰等,阐释了消毒与灭菌两个概念的区别。     

European citizen and consumer attitudes and preferences regarding beef and pork

This paper presents the combined mid-term findings of the consumer research components of two EU Sixth Framework Programme integrated projects concerning meat, ProSafeBeef and Q-PorkChains. The consumer pillar of ProSafeBeef carried out eight focus group discussions in May 2008, in France, Germany, Spain and the UK. Q-PorkChains conducted a large-scale, web-based, consumer survey in January 2008 in Belgium, Denmark, Germany, Greece and Poland. The first project provides a set of qualitative data from a small cohort of focus groups and the second a set of quantitative data from a larger consumer sample. This paper draws together the main findings of both projects and provides a comprehensive overview of European citizens’ and consumers’ attitudes towards and preferences regarding beef and pork. In general, consumers consider meat to be a healthy and important component of the diet. Consumers support the development of technologies that can improve the health attributes of meat products and guarantee eating quality, but they have a negative view of what they see to be excessive manipulation and lack of naturalness in the production and processing of beef products. In the Q-PorkChains study consumer and citizen segments are identified and profiled. Consumer segments were built upon the frequency and variety of pork consumption. The citizen segments were built upon their attitudes towards pig production systems. Overall, the relationship between individuals’ views as citizens and their behaviour as consumers was found to be quite weak and did not appear to greatly or systematically influence meat-buying habits. Future studies in both projects will concentrate on consumers’ acceptance of innovative meat product concepts and products, with the aim of boosting consumer trust and invigorating the European beef and pork industries.     

益生素、益生菌与结肠癌

介绍了益生素和益生菌及其作用机理。在动物模型中，有大量的数据证实益生素和益生菌能够预防癌症．而在人体内还没有直接实验证据。它们抑制癌症的确切机理目前尚不清楚，其抑制机理可能是：肠道菌群代谢活动的改变，肠道理化环境的改变，潜在的致癌物质的黏附和降解，肠道菌群的改变、抗癌或抗诱变物质的形成、提高宿主的免疫应答、影响宿主的生理活动以及发酵不能被消化的食物并形成有益代谢产物。     

节能节水型印染助剂和设备的现状

从节能、节水、缩短工艺流程和环保的角度出发，介绍了国内外研制开发的一系列新型节能、节水型印染助剂和染整设备。     

原花色素及其开发应用

对原花色素的结构、化学特性、制备、分析方法、应用前景作一综述,并重点讨论其生理功能,为在功能性食品、药物、化妆品等领域的深入研究和开发提供参考。     

天然香精香料与生物技术

天然香精香料是高价值的精细化工产品和食品添加剂,但原料来源有限且提取成本高。利用生物技术生产这类产品具有广阔的前景。简述了发酵工程、酶工程、细胞工程和基因工程在香精香料中的应用,并探讨了生物技术在香精香料中的应用前景。     

毛霉型低盐速成豆豉工业化生产工艺与设备

本文介绍了毛霉型低盐速成豆豉的工业化生产工艺及生产线的关键设备。     

组学技术与果蔬采后质量和安全控制

果蔬可以提供营养, 有利于人类健康, 而果蔬的后熟及其与环境的相互作用会影响果蔬采后的质量和安全。对果蔬生物学过程的了解和掌握是减少果蔬采后损失和保障果蔬采后质量和安全的关键。在过去的10多年, 基于组学技术的系统生物学在了解果蔬后熟及其与环境相互作用的分子机制方面得到了越来越多的应用。本文对此做了细致的总结, 指出了存在的不足, 并提出了未来的发展方向。     

Heritability and correlations for body condition score and dairy form within and across lactation and age

The objectives of the current study were to investigate the relationship between body condition score (BCS) and dairy form and changes in genetic parameters for BCS and dairy form within and across lactations and age. Body condition score and dairy form were obtained from the Holstein Association USA, Inc. Records were edited to include those cows classified between 24 and 60 mo of age and between 0 and 335 d in milk (DIM). A minimum of 20 daughters per sire and 15 cows per herd-classification visit were required. The dataset consisted of 135,178 records from 119,215 cows. Repeatability, multiple trait, and random regression models were used to analyze the data. All models included fixed effects for herd-classification visit, age within lactations 1, 2, and 3 or higher, and 5th-order polynomials for DIM. Random effects included sire and permanent environment for all models. Random regression models included age at classification nested within sire or DIM and lactation number nested within sire. Genetic variance for both BCS and dairy form was lowest in early lactation and highest in midlactation. Genetic correlations within and across lactations were high. The genetic correlation between DIM 0 in lactation 1 and DIM 305 in lactation 3 was estimated to be 0.77 for BCS and 0.60 for dairy form. The genetic correlation estimate between 30 mo of age at classification and 50 mo of age at classification was 0.94 for both dairy form and BCS. The repeatability models appeared to generate accurate evaluations for BCS or dairy form at all ages and stages of lactation.