从蜂王浆中提取蜂王酸的研究

目的 探讨从蜂王浆中提取蜂王酸(10-HAD)的工艺.方法 二次有机溶剂提取,二次调pH,用高效液相色谱法对10-HDA进行定性分析.结果 蜂王浆中10-HDA的最佳提取条件为:蜂王浆水溶液pH 10,加入乙醚提取杂质,再调PH 2加入乙醚提取10-HDA.结论 此法可从蜂王浆中高效提取10-HDA.     

蜂王浆中10-HDA提取工艺的研究

比较3种有机溶剂乙醚、乙酸乙酯、乙醇,采用5种方法提取蜂王浆中的10-HDA。利用高效液相色谱法得出:使用乙醇、采用振荡提取法的提取效果最好。通过正交试验优化提取工艺,结果表明,最佳提取工艺条件为萃取剂乙醇浓度100%vol,料液比1∶6,萃取时间60min,萃取1次,10-HDA提取率为33.893%。     

蜂王浆10-HDA提取和饮料加工技术研究

本论文研究峰王浆10-HDA饮料的加工技术。蜂王浆浓度在2％-10％，10-羟基癸烯酸(10-HDA)提取率高，蜂王浆提取液10-HDA有效成分利用率最好。蜂王浆10-HDA提取温度为75℃，pH值为5．0左右。以6000-7000r／min离心10min蜂王浆悬浮液变的透明。蜂王浆饮料的配方为蜂王浆澄清液80份，蜂蜜10份，蔗糖10份，柠檬酸0．1份，加水240份，哈蜜瓜香精适量。此饮料含10-HDA0．82mg/g。     

发酵液中提取10-HDA的研究

10-HDA为10-羟基-2-癸烯酸（10-Hydroxy-2-Decenoic酸），是蜂王浆中的特殊活性物质，抗菌、灭菌、强壮肌体和具有强烈抑制移植性AKR白血病、TA3乳腺癌及多种腹水型艾利虚癌等癌细胞生长的作用。蜂王浆中10-HDA的提取方法有乙醚萃取法、乙醇提取法、溶液沉淀结晶法、醇中沉淀结晶法及从发酵液中提取法等。不同浓度、不同体积的乙醇对产率及质量有影响；不同体积的反萃取剂水对产率也有影响；不同温度对结晶有影响。     

10-HDA抗菌实验的初步研究

探讨了从蜂王浆中提取10-HDA的工艺，并利用提取得到的10-HDA对实验室常见的几种细菌进行了抑菌活性实验，结果表明：10-HDA抑菌作用因菌种不同而最低抑菌浓度有所不同，大肠杆菌为0．625mg／mL、枯草芽孢杆菌为1．25mg／mL、金黄色葡萄球菌为2．5mg／mL，其抑菌效果为：大肠杆菌〉枯草芽孢杆杆菌〉金黄色葡萄球菌，实验表明对常见细菌有较好的抑制作用。     

蜂王浆在贮藏过程中5-羟甲基糠醛、10-羟基-2-癸烯酸及精氨酸双糖苷含量的变化

将10 个蜂王浆样品贮藏在不同温度（室温、4、－20、－80 ℃）和时间（15、45、65、80 d）条件下,采用高效液相色谱法检测其5-羟甲基糠醛（5-hydroxymethylfurfural,5-HMF）、10-羟基-2-癸烯酸（10-hydroxy-2-decanoicacid,10-HDA）和精氨酸双糖苷（arginyl fructosyl glucose,AFG）含量的变化。结果表明,蜂王浆样品中10-HDA的含量稳定,不随贮藏温度和时间的变化而变化;5-HMF和AFG的含量随贮藏温度升高及时间的延长而增加。因此5-HMF和AFG可作为衡量蜂王浆新鲜程度的指标性成分,而10-HDA不可以作为此标准。但10-HDA是蜂王浆中特有成分,其含量高低会直接影响蜂王浆的功效,故5-HMF、AFG与10-HDA三者结合对蜂王浆的品质进行评价会更加准确。     

蜂王浆泡腾片的制备及王浆酸溶出的测定

目的:为解决蜂王浆泡腾片中难溶成分10-羟基-2-癸烯酸（10-HDA）溶出率低的问题。方法:采用单因素实验和正交试验,研究了泡腾剂添加量、泡腾剂比例（柠檬酸:碳酸氢钠）、甜味剂添加量对蜂王浆泡腾片崩解时间及产气量的影响,并探索了不同食品添加剂对蜂王浆泡腾片中10-HDA溶出度的影响,获得了最佳配方。同时,利用X射线衍射（XRD）表征蜂王浆泡腾片的结晶度。结果:最佳配方为蜂王浆冻干粉10%,泡腾剂添加量45%,泡腾剂最佳比例（柠檬酸:碳酸氢钠）=1.5:1,甘露醇10%,罗汉果甜苷1%,硬脂酸镁0.8%,15%乳酸钙或者0.5%聚甘油脂肪酸酯,剩余以乳糖填充至100%。该配方下制得的蜂王浆泡腾片,口感良好、崩解迅速,并有效提高了10-HDA的溶出率,10-HDA的累计溶出率在15 min左右可使达到85%以上。结论:在蜂王浆泡腾片配方中加入乳酸钙或聚甘油脂肪酸酯可以有效提高10-HDA的溶出率,为提高蜂王浆相关产品中10-HDA溶出率提供了数据参考。     

10-HDA抗菌实验的初步研究

本文初步探讨了从蜂王浆中提取10-HDA的工艺，并利用提取得到的10-HDA对实验室常见的几种细菌进行了抑菌活性实验，结果表明：10-HDA抑菌作用因菌种不同而最低抑菌浓度有所不同，大肠杆菌0．625mg·mL^-1、枯草芽孢杆菌为1．25mg·mL^-1、金黄色葡萄球菌为2．5mg·mL^-1，其抑菌效果为：大肠杆菌〉枯草芽孢杆杆菌〉金黄色葡萄球菌，实验表明对常见细菌有较好的抑制作用。     

进出口蜂王浆及其制品中10-羟基-α-癸烯酸的分析与评估

目的 了解掌握蜂王浆及其制品中的主要营养成分质量情况，以确保蜂王浆在进出口贸易时得到相应的法律保障。方法 样品经乙醇提取，溶出10-羟基-α-癸烯酸(以下简称10-HDA)，并沉淀蛋白质，加内标后用乙醇定容，经离心或放置过夜，上清液过滤，HPLC测定。结果有代表性的进出口的蜂王浆及蜂王浆胶襄样品均含有一定量10-HDA。结论蜂王浆含果糖、氨基酸、多种酶、乙酰胆碱及丰富的维生素、芸香甙、促进性腺样物质和抗菌素类物质等，而其中10-HAD由于具有一定稳定性，因此是检验蜂王浆营养品质的主要指标。     

蜂王浆产品中10-羟基-2-癸烯酸的稳定性比较

10-羧基-2-癸烯酸(10-HDA)是蜂王浆特有的不饱和脂肪酸,在其质量标准中特别规定了含量要求.采用纳米技术制备纳米脂质体可提高其稳定性,以包封率为评定指标,采用乙醇注入-超声法制备了10-HDA纳米脂质体,并用液相色谱测定其中的10-HDA含量,比较5种蜂王浆产品中10-HDA的含量稳定性.结果发现,10-HDA纳米脂质体包封率可达98.3％,同时其含量最为稳定,而其它4种蜂王浆产品中10-HDA含量不稳定,随着时间的延长呈下降趋势.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

Focus on China's Paper Industry

In the English section of this issue, 〈China Paper Newsletters〉 will introduce ＂National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the ＇13th Five-Year Plan＇＂, ＂2013 Annual Report of China＇s Paper Industry＂, and news of projects and other policies.     

Listen to downstream & search for innovation

正Nowadays,textile enterprises are all taking efforts in transformation and upgrading,like improving producing capacity and optimizing production structure to face market downturn.It claimed a higher request to the standard of textile equipments.In the upcoming of ITMA ASIA+CITME 2014exhibition,this magazine have interviewed several branch associations and a series of relative enterprises,to summarize industrial developing status