小麦谷蛋白溶涨指数与蛋白质组分关系的研究

谷蛋白溶涨指数是一种蛋白质品质测定方法，是一定量面粉在SDS乳酸溶液中溶涨、离心后的面粉重量与面粉原始重量的比值。为了研究小麦谷蛋白溶涨指数与蛋白质组分的关系，采用两种蛋白质组分分离方法提取测定了21个小麦品种(品系)的蛋白组分含量，并采用C．Wang的方法测定了不同溶涨时间(0min、5min、20min)的谷蛋白溶涨指数。简单相关分析结果表明：溶涨时间为5min、20min时的谷蛋白溶涨指数与球蛋白含量呈显著负相关，与总蛋白、醇溶蛋白、可溶性谷蛋白、不溶性谷蛋白含量呈极显著正相关；各蛋白质组分含量对SIG的通径分析结果为：谷蛋白含量对SIG值的影响最大，其中不溶性谷蛋白含量起主导作用。因此，谷蛋白溶涨指数法能间接预测不溶性谷蛋白的含量。     

谷蛋白溶涨指数与面制食品质量控制

选用27个中国小麦样品，研究了谷蛋白溶涨指数对于评价中国白盐面条品质评价的适用性。谷蛋白溶涨指数与面带长度呈极显著负相关，与面带厚度呈极显著正相关。谷蛋白溶涨指数各时间(0min，5min，20min)与面条最佳煮面时间、鲜面条最大拉伸阻力、拉伸能量、拉伸长度均呈极显著正相关(除SIGO与最佳煮面时间呈显著正相关)；谷蛋白溶涨指数与可溶性谷蛋白、不溶性谷蛋白含量、面筋指数及蛋白质含量呈极显著正相关；谷蛋白溶涨指数与煮后面条表面韧性呈显著或极显著负相关，与剪切韧性呈显著正相关。谷蛋白溶涨指数可以作为一种品质指标控制面制食品的质量。     

影响谷蛋白溶涨指数测定因素研究

谷蛋白溶涨指数(简称SIC)是一定量小麦粉在SDS乳酸溶液中溶涨、离心后的面粉重量与小麦粉原始重量的比值。该方法适宜应用于小麦不溶性谷蛋白含量的评价，进而评价小麦的焙烤特性、面条和通心粉的蒸煮特性。研究表明，SDS溶液仅对蛋白质起作用，能将蛋白质大分子分解成小分子，而淀粉在SDS溶液中不分解，淀粉对测定结果无影响。随着温度升高，谷蛋白溶涨指数呈增高趋势。对测定的样品用量、试剂用量进行调整，可用百分之一天平得到较为准确的实验结果。     

文献导读

小麦谷蛋白溶涨指数与蛋白质组分关系的研究谷蛋白溶涨指数是一定量面粉在SDS乳酸溶液中溶涨、离心后的面粉重量与面粉原始重量的比值。为了研究小麦谷蛋白溶涨指数与蛋白质组分的关系,采用两种蛋白质组分分离方法提取测定了21个品种的小麦的蛋白组分含量,并采用C!W ang的方法测定了不同溶涨时间的谷蛋白溶涨指数。简单相关分析结果表明:溶涨时间为5m in、20m in时谷蛋白溶涨指数与球蛋白含量呈极显著正相关;各蛋白质组分含量对SIG的通径分析结果表明:谷蛋白对SIG值的影响最大,其中不溶性谷蛋白含量起主导作用。因此,谷蛋白溶涨指数法…     

蛋白质组分分析方法比较研究

采用蛋白质连续累进提取法与组分快速提取法测定了21个小麦面粉样品的蛋白质组分，以比较两种蛋白质组分分析方法的特点。连续累进提取法将小麦蛋白质分离成清蛋白、球蛋白、醇溶蛋白和谷蛋白；快速提取法将小麦蛋白质分离成单体蛋白、可溶性谷蛋白和不溶性谷蛋白。结果表明：单体蛋白与清蛋白、球蛋白、醇溶蛋白含量及清蛋白、球蛋白、谷蛋白之和均无关系；可溶性谷蛋白含量与清蛋白、弱化度呈负相关，与醇溶蛋白、谷蛋白、沉淀值呈极显著或显著正相关；不溶性谷蛋白与醇溶蛋白、谷蛋白、沉淀值、稳定时间、评价值、弱化度呈极显著或显著相关。连续累进提取法适合于小麦品质常规检测，快速提取法适用于小麦早代材料品质检测。两种方法对于预测小麦的加工品质有着相同的重要作用，应根据样品量及检测精度进行选择。     

谷蛋白溶涨指数(SIG)在小麦品质鉴定上的应用价值分析

选用33个小麦品种（系），通过谷蛋白溶涨指数（Swelling index of glutenin，简称SIG）与小麦商品品质和加工品质间的相关性分析，评价SIG在小麦育种中应用的可能性。33个供试小麦样品的SIG值与Zeleny沉淀值、W值和拉伸面积等指标相关系数分别为0．906、0．921和0．873，均这极显著正相关水平，SIG值可预测小麦品种（系）的蛋白质质量。根据SIG值取值范围对小麦品种（系）进行品质分类，与采用国家标准具有同等效果，是一种样品用量少、操作简便快速、结果精确的小麦早代品质鉴定的有效方法。     

小麦谷蛋白溶胀指数与面团特性及面条品质相关性分析

选用30种小麦,通过谷蛋白溶胀指数(SIG)与面团特性及面条品质的相关性研究,进而评价谷蛋白溶胀指数在预测蛋白质品质中的应用.结果表明:SIG与面团品质参数形成时间、稳定时间、弱化皮、拉伸曲线面积具有显著相关性,相关系数分别为0.537,0.547,-0.516,0.469;SIG20与面条品质参数最佳蒸煮时间、咀嚼性、弹性具有显著相关性,相关系数分别为0.455,0.477,-0.521,与硬度具有相关性,相关系数为0.334.谷蛋白溶胀指数比其他3种预测方法更简单,相关性更好,更适合中国小麦蛋白质品质预测,可以用于指导品质育种、谷物化学研究、面制食品加工.     

谷蛋白大聚体在小麦加工中的作用

谷蛋白大聚体(GMP)是小麦籽粒中最重要的蛋白质聚合体,不溶于1.5%SDS溶液,且分子质量较大,以颗粒形式存在,粒径范围为1~300μm;其含量和分子结构与食品加工品质密切相关,在面制食品加工中的作用远大于可溶性谷蛋白聚合体和单体蛋白。谷蛋白大聚体含量高的小麦品种,其面筋、面团的强度和弹性较大,面包烘烤品质较好,面条拉伸特性较好。谷蛋白大聚体在面团和面过程中会发生解聚,其含量、粒径和分子质量均降低;而在面团醒发过程中又会发生重聚。面条面坯形成过程中,谷蛋白大聚体含量的降低程度远低于传统面团,而凝胶强度的变化趋势则与传统面团相反。     

食品中小麦致敏成分的常规PCR检测方法的建立

建立了一种常规PCR方法用于检测一系列原料和加工食品中小麦致敏成分的DNA。针对小麦的ω-醇溶谷蛋白设计了一对大小为185 bp的引物。检出限为10 ng。该法能检测热加工食品中的小麦DNA,并具有良好的特异性,可作为食品无谷蛋白标识的检测方法。同时它弥补了免疫化学方法的不足,并为乳糜泻患者的食品安全提供保障。     

小麦加工品质性状与馒头质量性状的相关性

以２３个小麦品种为材料，对其２２个加工品质性状与蒸制的馒头质量性状间的相关性进行了系统分析，研究了高分子量谷蛋白亚基构成与馒头体积的关系。提出了用沉淀值、公差指数、软化度三个加工品质性状指标，作为评价馒头质量的间接指标     

Encapsulation of food ingredients

Microencapsulation is a relatively new technology that is used for protection, stabilization, and slow release of food ingredients. The encapsulating or wall materials used generally consist of starch, starch derivatives, proteins, gums, lipids, or any combination of them. Methods of encapsulation of food ingredients include spraydrying, freeze‐drying, fluidized bed‐coating, extrusion, cocrystallization, molecular inclusion, and coacervation. This paper reviews techniques for preparation of microencapsulated food ingredients and choices of coating material. Characterization of microcapsules, mechanisms of controlled release, and efficiency of protection/ stabilization of encapsulated food ingredients are also presented.     

STANDARD SIZING AND FIT TESTING APPLIED TO WOMEN'S HOSIERY

The monograph deals with a critical review of the recent research work and development on ramie, a long vegetable bast fibre. The review is divided into two parts. Part I discusses the progress of recent work on ramie, chemical components like fibre degumming, its effects on fibre composition, chemical constituents, i.e. hemicellulose, cellulose, non-cellulosic and mineral matters. Besides various chemical properties of native and modified fibres such as accessibility, infrared, cellulose I–V, DP, grafting, cross linking and resin finishing and dyeing etc. are dealt with.     

5—THE CONSTITUTION OF THE EPICUTICLE OF WOOL

Epicuticle, isolated from wool via the Allwörden reaction, was examined by electron microscopy and analysed chemically. It is proteinaceous; lipids and carbohydrates could not be detected. The component amino acids are: cystine, glycine, glutamic acid, serine, valine, alanine, lysine, α-amino-adipic acid, and threonine. A tentative model for the epicuticle is proposed.     

Mycotoxins in botanicals and dried fruits: A review

Botanicals are used in many countries for medicinal and general health-promoting purposes. Numerous natural occurrences of mycotoxins in botanicals and dried fruits have been reported. Aflatoxins or ochratoxin A (OTA) have been found in botanicals such as ginseng, ginger, liquorice, turmeric, and kava-kava in the USA, Spain, Argentina, India, and some other countries, while fumonisins have been found in medicinal wild plants in South Africa and in herbal tea and medicinal plants in Turkey. Zearalenone was identified in ginseng root. Dried fruits can be contaminated with aflatoxins, OTA, kojic acid, and, occasionally, with patulin or zearalenone. One main area of concern is aflatoxins in dried figs; bright greenish yellow fluorescence under ultraviolet light is associated with aflatoxin contamination. OTA in dried vine fruits (raisins, sultanas, and currants) is another concern. There are also reports of aflatoxins in raisins and OTA in dried figs, apricots, dried plums (prunes), dates, and quince. Maximum permitted levels in the European Union include 4 µg kg^-1 for total aflatoxins in dried fruit intended for direct consumption and 10 µg kg^-1 for OTA in dried vine fruit. This review discusses the occurrence of mycotoxins in botanicals and dried fruits and analytical issues such as sampling, sample preparation, and methods for analysis. Fungal contamination of these products, the influence of sorting, storage, and processing, and prevention are also considered.     

Avena sativa (Oat), A Potential Neutraceutical and Therapeutic Agent: An Overview

The aim of the present review article is to summarize the available information related to the availability, production, chemical composition, pharmacological activity, and traditional uses of Avena sativa to highlight its potential to contribute to human health. Oats are now cultivated worldwide and form an important dietary staple for the people in number of countries. Several varieties of oats are available. It is a rich source of protein, contains a number of important minerals, lipids, β-glucan, a mixed-linkage polysaccharide, which forms an important part of oat dietary fiber, and also contains various other phytoconstituents like avenanthramides, an indole alkaloid-gramine, flavonoids, flavonolignans, triterpenoid saponins, sterols, and tocols. Traditionally oats have been in use since long and are considered as stimulant, antispasmodic, antitumor, diuretic, and neurotonic. Oat possesses different pharmacological activities like antioxidant, anti-inflammatory, wound healing, immunomodulatory, antidiabetic, anticholesterolaemic, etc. A wide spectrum of biological activities indicates that oat is a potential therapeutic agent.     

Bioactivation of Phytoestrogens: Intestinal Bacteria and Health

Phytoestrogens are polyphenols similar to human estrogens found in plants or derived from plant precursors. Phytoestrogens are found in high concentration in soya, flaxseed and other seeds, fruits, vegetables, cereals, tea, chocolate, etc. They comprise several classes of chemical compounds (stilbenes, coumestans, isoflavones, ellagitannins, and lignans) which are structurally similar to endogenous estrogens but which can have both estrogenic and antiestrogenic effects. Although epidemiological and experimental evidence indicates that intake of phytoestrogens in foods may be protective against certain chronic diseases, discrepancies have been observed between in vivo and in vitro experiments. The microbial transformations have not been reported so far in stilbenes and coumestans. However, isoflavones, ellagitanins, and lignans are metabolized by intestinal bacteria to produce equol, urolithins, and enterolignans, respectively. Equol, urolithin, and enterolignans are more bioavailable, and have more estrogenic/antiestrogenic and antioxidant activity than their precursors. Moreover, equol, urolithins and enterolignans have anti-inflammatory effects and induce antiproliferative and apoptosis-inducing activities. The transformation of isoflavones, ellagitanins, and lignans by intestinal microbiota is essential to be protective against certain chronic diseases, as cancer, cardiovascular disease, osteoporosis, and menopausal symptoms. Bioavailability, bioactivity, and health effects of dietary phytoestrogens are strongly determined by the intestinal bacteria of each individual.     

蒽醌助剂对乙二醇溶剂脱胶苎麻纤维性能的影响

为解决苎麻在乙二醇有机溶剂脱胶中纤维易被氧化而导致性能下降的问题,在乙二醇溶剂中添加助剂蒽醌对苎麻进行脱胶,并对蒽醌不同添加量下制得的纤维进行结构和性能表征。结果表明:纤维中半纤维素含量随蒽醌添加量的增加而升高,纤维的聚合度、结晶度、物理力学性能先升高后降低,纤维的残胶率和线密度先降低后升高;当蒽醌质量分数为0.3% 时,这些性能均达到最佳值,此时纤维的聚合度、结晶度、制成率、断裂强度、断裂伸长率、断裂功比不加蒽醌时分别提高了7.32%、20.53%、1.46%、9.55%、6.89%、33.33%,纤维的残胶率、线密度比不加蒽醌时分别降低了17.91%、7.24%。     

中美主要烟草品种亲源分析与烟草育种

本文分析了中美300多个烤烟,80多个晒晾烟主要育成品种的亲源关系,从中可以看出,品质与抗病育种是烟草育种的主体,由Orinoco衍生的Hicks、Virginiabrightleaf和400及后来育成的NC95、Coker139和Coker319等是烤烟品质育种和抗病育种的主体亲本;由WhiteBurley衍生的Kentucky16、Burley21和由MDRobinson育成的Maryland64、Maryland609分别是白肋烟与马里兰烟品质、抗病育种的主体亲本;烟草抗黑胫病、青枯病、根结线虫病、根黑腐病、烟草普通花叶病和野火病的抗源分别来自Florida301、TI448A、TI706、N. debnexyi、N. glutinosa和N. longiflora等原始栽培品种或野生种。美国烟草育种经历了从品质到多抗,再到综合优良性状改良的阶梯式发展过程。而我国优质、多抗育种起步较晚,仍存在品质与抗性、品质与易烤性关系研究较少,外源优良基因利用较少,遗传基础狭窄等问题,本文就近期烟草育种的目标和途径进行了初步探讨。      

Influence of different non-grain commodities on the population growth of Trogoderma granarium Everts (Coleoptera: Dermestidae)

We investigated the population growth of the khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae) on seven groups of commercially available non-grain commodities. Six powdered spices were used in the first group of experiments: black pepper, clove, nutmeg, allspice, cinnamon and turmeric. The second group of the tested commodities included seven animal products: powdered cow milk, powdered pork zelatin, sheeps’ wool, goat’s skin, ducks’ feathers, dry dog food and dry cat food. The third group of commodities was consisted of six herbs: oregano, spearmint, basil, coriander, laurel and marjoram. The fourth group of commodities contained ten pulses: chickpeas, lentil, split peas, black-eyed peas, beans, soybean flour and whole kernels, lima beans, mung bean, and broad beans. The fifth group comprised six dried fruits: Corinthian currants, sultanas, banana chips, melons, apricots and figs. The sixth group was consisted of five non-grain commodities: cottonseed cake, tobacco, black tea, Turk kahvesi and potato flour. The seventh group included seven nuts: sunflower seeds, pumpkin seeds, pistachios, roasted chickpeas (yellow), almonds, hazelnuts and walnuts. Finally, six cracked containment categories (0% cracked kernels, 5% cracked kernels and 95% intact kernels, 10% cracked kernels and 90% intact kernels, 25% cracked kernels and 75% intact kernels, 50% cracked kernels and 50% intact kernels and 100% cracked kernels) from five pulses were tested: chickpeas, black-eyed peas, mung bean, soybean and split peas. The highest progeny production (3.01 individuals per vial) was recorded on powdered cow milk. On pistachios, split peas, sunflower seeds, soybean flour, pumpkin seeds, walnuts, almonds and coriander, T. granarium built high population densities rapidly, while on roasted chickpeas, cottonseed cake, hazelnuts, chickpeas, dog food and lentils, its population growth was much less. Broad beans, melons, figs, lima beans, beans, Corinthian currants, pork zelatin and potato flour were less suitable diets for the development of this species. On black pepper, clove, nutmeg, allspice, cinnamon, turmeric, sheeps’ wool, goat’s skin, ducks’ feathers, cat food, sultanas, banana chips, apricots, tobacco, black tea, Turk kahvesi, oregano, spearmint, basil, laurel and marjoram, no progeny production was recorded. The proportion of 100% cracked black-eyed peas or mung beans was more suitable for the population growth of T. granarium. Also, the percentages of 50% cracked chickpeas or 10% cracked soybeans enhanced the development of the species, in comparison with the whole kernels of each pulse. Our study indicated that several non-grain commodities are beneficial for the population growth of T. granarium, a fact that should be seriously taken into account in international trade, as this pest may utilize them as “vehicles” of expansion.     

Detection and characterization of engineered nanoparticles in food and the environment

Nanotechnology is developing rapidly and, in the future, it is expected that increasingly more products will contain some sort of nanomaterial. However, to date, little is known about the occurrence, fate and toxicity of nanoparticles. The limitations in our knowledge are partly due to the lack of methodology for the detection and characterisation of engineered nanoparticles in complex matrices, i.e. water, soil or food. This review provides an overview of the characteristics of nanoparticles that could affect their behaviour and toxicity, as well as techniques available for their determination. Important properties include size, shape, surface properties, aggregation state, solubility, structure and chemical composition. Methods have been developed for natural or engineered nanomaterials in simple matrices, which could be optimized to provide the necessary information, including microscopy, chromatography, spectroscopy, centrifugation, as well as filtration and related techniques. A combination of these is often required. A number of challenges will arise when analysing environmental and food materials, including extraction challenges, the presence of analytical artifacts caused by sample preparation, problems of distinction between natural and engineered nanoparticles and lack of reference materials. Future work should focus on addressing these challenges.