羊皮胶原蛋白乳化性与乳化稳定性的研究

以实验室自制羊皮胶原蛋白为原料,利用柠檬酸和胃蛋白酶进行胶原蛋白的提取,并研究不同浓度、pH和电解质对胶原蛋白乳化性和乳化稳定性的影响。结果表明,所提取的胶原蛋白保持良好的结构,其乳化性随蛋白浓度增加而增大。在远离等电点时,有良好的乳化性;接近等电点pH=5时乳化性最差。在较低NaCl浓度范围内,NaCl的加入对乳化性有促进作用。乳化稳定性的变化较为复杂,有时与乳化性的变化相反,乳化性较差的点表现出了较好的乳化稳定性,反之亦然,建议综合考虑乳化性和乳化稳定性的变化获得最佳改性效果。     

介质对蛋清蛋白乳化性及乳化稳定性的影响

探讨了蛋白浓度、pH、温度、氯化钠、蔗糖、可溶性淀粉对蛋清蛋白乳化性及乳化稳定性的影响。结果表明:添加蔗糖及可溶性淀粉、提高蛋白浓度都能提高蛋白的乳化性及乳化稳定性,提高氯化钠浓度、温度和pH,蛋白的乳化性及乳化稳定性都是先增后减。这些变化规律为开发和利用蛋清蛋白提供一定理论依据。     

不同处理方式对鹰嘴豆分离蛋白乳化性质的影响

研究发现微波、超声波、超高压、不同的pH、不同的油含量和不同的离子浓度等都能够影响鹰嘴豆分离蛋白的乳化性质：当微波处理时间为60s,其乳化活性和乳化稳定性都达到最大值;当超声波处理时间为4min时,其乳化活性和乳化稳定性达到最大值;当压力为400MPa时,其乳化活性和乳化稳定性达到最大值;当pH在5.0时,鹰嘴豆蛋白的乳化活力最小,乳化稳定性最高;当NaCl浓度在0.2mol/L时,乳化活性最小,乳化稳定性最高;当加油量在10～30mL范围内,乳化活性逐渐增加,乳化稳定性逐渐降低。     

食用乳化剂和乳化增稠剂的乳化性能的测定

本试验采用一种简单快速的乳化测定方法比较几种常用蛋白类乳化剂、乳化增稠荆和酯类乳化剂的乳化性能和乳化稳定性.为生产单位和使用单位筛选乳化剂及各类食品选择乳化剂提供一定的参考价值.     

大豆分离蛋白乳化性的研究

采用蛋白质乳化容量电导法,对不同浓度、ＰＨ和酶水解条件下大豆分离蛋白乳化容量和乳化稳定性进行测定,结果表明：大豆蛋白的乳化性在低密度时随浓度上升而增加,浓度达到６％以后趋于稳定;等电点时（ＰＨ４．５）,乳化性最差,偏离等电点后尤其在偏碱性条件下,乳化性明显增加,酶水解后,乳化性变化产大,水解度１７％时,乳化性最佳。     

丝胶蛋白的乳化性能及其影响因素的研究

以废蚕茧为原料,通过高温煮茧得到丝胶蛋白溶液,测定丝胶蛋白溶液的乳化活性、乳化稳定性等指标,结果表明:丝胶蛋白的乳化性能较好。探讨了影响丝胶蛋白乳化性能的因素。乳化性受蛋白质浓度、pH值、离子强度、温度等因素影响较大,具体表现为乳化性能随着蛋白质浓度的增加逐步增大;随pH值的增加先逐渐减小,然后又逐渐增加,在pH值为4时,乳化活性和乳化稳定性达到最小值;乳化活性和乳化稳定性在20℃和50℃之间是随温度的升高而增加,50℃以上随温度的升高而减小;且其受离子浓度影响也是先增后减,在离子浓度为0.6 mol/L时乳化性能最好。     

提高大豆分离蛋白乳化性及乳化稳定性的研究

为了拓宽大豆分离蛋白在食品中的应用，提高其乳化性及乳化稳定性。研究了大豆分离蛋白物理、化学和生物改性，并对改性前后大豆分离蛋白的乳化性及乳化稳定性进行了比较。同时也探讨了pH对大豆分离蛋白及其改性物形成乳状液的影响，并利用成膜蛋白质分子所受的相互作用解释了蛋白质的乳化稳定性受外界条件和内部因素所发生的变化。研究发现适度改性可以提高大豆分离蛋白乳化性及乳化稳定性；碱性有利于大豆分离蛋白及其改性物乳化性的提高；而且用吸光值比(K)可较好地表示乳化稳定性．     

亚麻籽胶的乳化性质

重点研究了亚麻籽胶的乳化性质，实验结果表明。亚麻籽胶的质量分数、溶解温度、乳化温度、加油量以度贮存温度等对亚麻籽胶的乳化性质都有影响。质量分数增加，亚麻籽胶的乳化稳定性增强；加油量增多。亚麻籽胶的乳化稳定性下降；溶解温度升高能提高亚麻籽胶的乳化稳定性；而乳化温度和贮存温度越高，亚麻籽胶乳状液越不稳定。由于亚麻籽胶与阿拉伯胶在相对分子质量、均方旋转半径、粘度、疏水性氨基酸含量上的差异，导致了亚麻籽胶与阿拉伯胶乳化性质的差异．     

蒸谷米糠蛋白乳化性的研究

研究在不同质量浓度、不同温度、不同pH值、不同离子强度、不同蔗糖质量浓度等条件下,蒸谷米糠蛋白的乳化性和乳化稳定性的变化规律,并和大豆分离蛋白做比较。结果发现:蒸谷米糠蛋白乳化性和乳化稳定性均高于大豆分离蛋白,并变化幅度较大;温度、pH值对蒸谷米糠蛋白乳化性和乳化稳定性影响也较大,pH值接近中性可以平衡乳化性和乳化稳定性相互制约。     

物理、化学、生物法处理蛋黄颗粒对其乳化特性影响的研究进展

蛋黄颗粒（Egg Yolk Granules, EYGs）是蛋黄经过稀释离心后的沉淀部分,因其主要成分为脂蛋白,所以具有一定的乳化性能。天然颗粒的乳化性能由于其内部结构的影响,乳化性能较差,但经过不同方式处理后可使其乳化性能得到明显改善。然而到目前为止,关于蛋黄颗粒乳化性能的改善方式和效果等仍缺乏深入探讨和系统总结。基于此,该研究综述了几种较为广泛的处理方式,包括机械处理、加热处理、外源添加处理、化学处理和酶法处理等对蛋黄颗粒乳化性和乳化稳定性的改善效果,发现大部分方法均可不同程度增强蛋黄颗粒的乳化性或乳化稳定性,且作用机制不尽相同。该研究阐述了各种处理方式对蛋黄颗粒结构、乳化性能的影响及其作用机制,为改善蛋黄颗粒乳化性能、明确作用机理提供了理论参考。同时,对蛋黄颗粒的发展方向提出展望,以期提高蛋黄颗粒在未来食品领域中的应用价值。     

Applications of emerging imaging techniques for meat quality and safety detection and evaluation: A review

With improvement in people's living standards, many people nowadays pay more attention to quality and safety of meat. However, traditional methods for meat quality and safety detection and evaluation, such as manual inspection, mechanical methods, and chemical methods, are tedious, time-consuming, and destructive, which cannot meet the requirements of modern meat industry. Therefore, seeking out rapid, non-destructive, and accurate inspection techniques is important for the meat industry. In recent years, a number of novel and noninvasive imaging techniques, such as optical imaging, ultrasound imaging, tomographic imaging, thermal imaging, and odor imaging, have emerged and shown great potential in quality and safety assessment. In this paper, a detailed overview of advanced applications of these emerging imaging techniques for quality and safety assessment of different types of meat (pork, beef, lamb, chicken, and fish) is presented. In addition, advantages and disadvantages of each imaging technique are also summarized. Finally, future trends for these emerging imaging techniques are discussed, including integration of multiple imaging techniques, cost reduction, and developing powerful image-processing algorithms.     

采前喷施壳聚糖复合膜对猕猴桃软腐病的防控及其保鲜作用

以‘贵长’猕猴桃为试材,通过病原菌分离、致病性测定和DNA测序鉴定了修文县猕猴桃软腐病病原菌,并选用壳聚糖、钙盐和糊精分别与茶多酚、甘氨酸、柠檬酸、抗菌肽混合制备和筛选了复合膜剂,研究了采前幼果期和壮果末期果面喷施壳聚糖复合膜对猕猴桃软腐病的防控及其保鲜作用。结果表明,修文县猕猴桃软腐病病原菌为葡萄座腔菌（Botryosphaeria dothidea）和拟茎点霉菌（Phomopsis sp.）;采前喷施不同壳聚糖复合膜对其软腐病的防效均达60%以上（添加茶多酚防效86.54%、甘氨酸防效61.54%、柠檬酸防效71.15%、抗菌肽防效69.23%）,显著降低丙二醛（MDA）积累,提高果实的超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和过氧化物酶（POD）活性,诱导增强果实的抗病性。同时,该复合膜能有效地增加果实单果质量和体积,显著提高果实VC、可溶性固形物、可溶性总糖、可滴定酸、叶绿素和蛋白质的含量,促进猕猴桃产量的增加和品质的改善。此外,施用该复合膜还能有效提高和维持果实硬度、降低果实呼吸强度以及果实质量损失率和营养物质的损失,明显抑制果实可溶性固形物和可溶性总糖含量的上升速率和延缓组织的衰老软化,从而提高了猕猴桃耐贮性。研究结果为猕猴桃优质栽培、病害有机防控和果实绿色保鲜提供了科学依据和新途径。     

可持续生产再生资源表面活性剂的国际研究进展（网络首发、推荐阅读）

表面活性剂是重要的化学产品,作为乳化剂和界面改性剂应用于家用洗涤剂、个人护理产品、油漆和涂料、食品、化妆品和制药工业中。聚焦表面活性剂在研究和开发方面取得的最新国际进展,尤其以改善其在整个生命周期的生态可持续性,包括以再生资源为原料的衍生物、使用绿色制造原则生产、以及在消费者使用和处置过程中提高生物相容性和生物降解性。生物基表面活性剂来源于植物油、多糖、蛋白质、磷脂和其他可再生资源,目前约占表面活性剂市场的24%,这一比例预计还将增加,特别是在亚洲。可再生能源的使用对消费者很有吸引力,因为这能减少二氧化碳（一种与气候变化有关的温室气体）的产生。酶可以通过减少有机溶剂、水和能源的使用,减少副产品和废物的形成,大大提高工艺的可持续性。在用于合成表面活性剂的生物酶中,脂肪酶是最强效的,因其具有较高的生物催化活性、操作稳定性和形成或切割酯、酰胺和硫代酯键的能力。为了使酶成为表面活性剂的强效催化剂,需对其进一步研究开发,以提高催化生产率、稳定性和降低其购买成本。     

Effects of Dietary Components on Cancer of the Digestive System

Cancer is the second leading cause of death in developed countries and poor diet and physical inactivity are major risk factors in cancer-related deaths. Therefore, interventions to reduce levels of smoking, improve diet, and increase physical activity must become much higher priorities in the general population's health and health care systems. The consumption of fruit and vegetables exerts a preventive effect towards cancer and in recent years natural dietary agents have attracted great attention in the scientific community and among the general public. Foods, such as tomatoes, olive oil, broccoli, garlic, onions, berries, soy bean, honey, tea, aloe vera, grapes, rosemary, basil, chili peppers, carrots, pomegranate, and curcuma contain active components that can influence the initiation and the progression of carcinogenesis, acting on pathways implied in cell proliferation, apoptosis and metastasis. The present review illustrates the main foods and their active components, including their antioxidant, cytotoxic, and pro-apoptotic properties, with a particular focus on the evidence related to cancers of the digestive system.     

Proximate composition and mineral contents of the blue crab (Callinectes sapidus) breast meat, claw meat and hepatopancreas

The objective of this study was to determine the nutritional composition of the breast, claw meat and hepatopancreas of the blue crab (Callinectes sapidus). Samples were subjected to proximate (protein, fat, ash and moisture) and calcium, magnesium, phosphorus, potassium and sodium (Ca, Mg, P, K and Na) analyses. Protein, fat, ash and moisture of the breast, claw meat and hepatopancreas of the blue crab averaged 19.05, 0.59, 2.10 and 76.85 g/100 g, respectively. The results have revealed that this species is a rich source of protein, Ca, Mg, P and Na. Claw meat had higher protein concentrations (19.55 g/100 g) than both breast meat and hepatopancreas (18.81 g/100 g). Na was predominant element among minerals analysed. There were significant differences between Ca, Mg, P, K and Na contents of claw, breast meat and hepatopancreas of the blue crab. Information on the nutrient composition is needed to facilitate the processing, utilisation and marketing of blue crab products. Blue crab could balance human nutrition and could be used as an alternative dietary supplement of proteins and mineral matter.     

中国与主要发达国家牛羊禽肉与猪肉比价分析

分析了1995年以来美国、欧盟、日本、韩国和我国猪牛羊禽肉价格走势。除日本外,其余国家牛肉和猪肉价格均呈上涨趋势;美国、欧盟和中国羊肉价格以及美国、欧盟、韩国和中国鸡肉均呈涨势。日本和韩国牛肉/猪肉比价显著高于其它国家,总体呈降势,美国、欧盟和中国则呈增加趋势。我国牛羊肉/猪肉比价季节性不明显。我国和韩国鸡肉/猪肉比价处于低位。     

Bioaccessibility of Se, Cu, Zn, Mn and Fe, and heme iron content in unaged and aged meat of Hereford and Braford steers fed pasture

The content and the bioaccessibility of Se, Cu, Zn, Mn, and Fe were determined in unaged and aged meat (14days) from the Psoas major (PM), Gluteus medius (GM) and Longissimus dorsi (LD) muscles of Hereford (H) and Braford breed (B) steers fed pasture. Furthermore, the content of heme-Fe was determined in the same muscles. The H had a lower content of Cu and a higher content of Fe. Also, H had more heme-Fe than B. The bioaccessibility in unaged meat for Se, Cu, Zn, Mn and Fe ranged between 75 and 91%, 30 and 45%, 40 and 68%, 55 and 95%, and 60 and 70%, respectively. After aging, the bioaccessibility for the same minerals ranged between 58 and 80%, 30 and 48%, 40 and 58%, 75 and 95%, and 59 and 70%, respectively. Aging affected negatively the Se content and its bioaccessibility, in the two breeds. Also, the heme-Fe content was negatively affected by aging in all muscles and breeds.     

纺织检测技术与仪器发展的回顾及前瞻

由于数学、物理学、机械工程学、电子学，特别是微电子学、计算机网络技术和数据处理技术的发展，纺织检测理论和技术取得了长足的发展，纺织检测仪器的自动化水平、检测功能综合及复合程度都有了极大提高。随着市场经济的发展和全球经济一体化进程的推进，纺织材料品质检验工作将逐步完善实施第三方客观公证检验制度，并且将增加新的检测项目，数量逐步加大，逐步建立起以产品质量法为基准，标准和合同质量承诺相结合的质量保证体系。     

Composites from Bast Fibres-Prospects and Potential in the Changing Market Environment

Abstract

Composite materials reinforced with natural fibres, such as flax, hemp, kenaf and jute, are gaining increasing importance in automotive, aerospace, packaging and other industrial applications due to their lighter weight, competitive specific strength and stiffness, improved energy recovery, carbon dioxide sequestration, ease and flexibility of manufacturing and environmental friendliness besides the benefit of the renewable resources of bast fibres. The market scenario for composite applications is changing due to the introduction of newer biodegradable polymers, such as PLA synthesized from corn, development of composite making techniques and new stringent environmental laws requiring improved recyclability or biodegradability for industrial applications where stress bearing capacities and micro-mechanical failures dictate serviceability. Bast fibre reinforced composites, made from biodegradable polymers, will have to compete with conventional composites in terms of their mechanical behaviour. Biocomposites, in which natural fibres, such as kenaf, jute, flax, hemp, sisal, corn stalk, bagasse or even grass are embedded in a biodegradable matrix, made as bioplastics from soybean, corn and sugar, have openedup new possibilities for applications in automotive and building products. Obviously, new approaches to research and development will be required to improve their mechanical properties, such as tensile, bending and impact resistance to match their performance and commercial competitiveness against petroleum based products. The research community has to look at the various possibilities of combining natural fibres, such as sisal, flax, hemp and jute with polymer matrices from non-renewable and renewable resources to develop cost effective biocomposites. This paper will review the newer products and techniques that can improve the properties of bast fibre based composites as well as potential structural and non-structural applications which can increase their market share.     

Bioactive Components and Health-Promoting Properties of Yuzu (Citrus ichangensis × C. reticulate)

Yuzu (Citrus ichangensis × C. reticulate) fruit is an important functional food that possesses several health-promoting properties. It has been widely used in commercial medical products, healthy foods, and cosmetics in many countries. Yuzu is a rich source of wide variety of non-nutritive compounds, such as flavonoids, anthocyanins, phenolic acids, carotenoids, and tannins; as well as nutritive compounds such as sugars, proteins, vitamins, fibers, and minerals. Yuzu fruit (juice, peel, and seeds) and its bioactive compounds have been demonstrated to have numerous functional properties, such as antioxidant, anti-inflammatory, anticancer, antiplatelet, angiogenesis, and antimicrobial properties, both in vitro and in vivo. These diverse applications provided by the yuzu fruit (juice, peel, and seeds) and its bioactive compounds are of great industrial importance. This review summarizes the composition, nutritional values, and functional properties of yuzu fruit, and their biological activity in relation to their potential impact on human health.