薯蔓多糖的纯化工艺

采用活性炭脱色,选取时间、温度、活性炭用量3个因素进行正交实验,用脱色率和多糖含量作为考察指标。采用三氯乙酸法和Sevage法去除蛋白质,主要研究其浓度与体积比对蛋白质去除率和多糖损失率的影响。结果表明：40℃、40min、活性炭用量为1．0％时去除色素效果最好,脱色率为21．98％,多糖保留率为94．09％。薯蔓多糖溶液与5％TCA溶液体积比为1：2时,去除蛋白质效果较好;Sevage（氯仿：正丁醇=4：1）溶液与薯蔓多糖溶液体积比为1：1时,去除蛋白质效果较好。     

墨声波法提取香菇培养基废弃物中活性多糖的研究

为了更好的开发利用香菇资源,本研究以香菇培养基废弃物为材料、多糖为研究对象,通过对比分析和L9（3^4）正交试验设计等研究方法,重点考察不同超声功率、料液比、超声时间对香菇培养基废弃物中多糖提取率的影响。结果表明,最佳提取工艺条件为超声时间45min,料液比1：30,超声功率300W,多糖提取率平均可达3．46％。     

仙草色素的提取研究

采用常用的正交试验法[L16（4^5）]和单因素试验法相结合的方法优选了提取仙草色素的方法，并对该提取工艺的条件进行了初步探索。试验结果表明，各因素对仙草色素提取效果的影响程度依次为：浸提酸度〉原料粒度〉浸提温度〉浸提剂；最佳提取工艺条件是：浸提酸度pH=14，原料粒度为40目，浸提温度为室温（25℃），浸提剂为水，浸提时间为90min；此时色素的提取率可达12．44％。另外，微波或超声波对仙草色素的提取有明显促进作用。     

微波辅助从羊肺中提取肝素钠的工艺研究

以羊肺为原料,采用微波辅助法及盐解、沉淀剂除蛋白质的方法提取和分离肝素钠。在单因素试验基础上,设计L9（3^4）正交试验确定最佳提取工艺条件。结果表明,最佳提取工艺为料液比1：15（g：mL）,微波作用时间180S,微波功率480W,沉淀剂用量为0-8％,此条件下肝素钠得率为294．78mg／kg。     

龙井绿茶茶多酚提取工艺研究

为了提高茶多酚的得率和纯度,以龙井绿茶为原料,对茶多酚进行乙醇溶液提取、超声波和微波辅助提取。醇提的最佳条件为乙醇浓度50％,浸提4次,每次45min,温度为70℃,液固比为20：1,最大浸提率为24．45％。微波辅助提取最佳条件为预浸30min,乙醇浓度40％,微波解冻档浸提4min,浸提2次,液固比为40：1,最大浸提率为24．70％。超声波辅助浸提最佳条件为乙醇浓度80％,浸提温度50℃,浸提时间25min,浸提2次,液固比为14：1,最大浸提率为24．72％。结果表明：微波与超声波提取率稍高于醇提,但三者差别不大。     

微波辅助提取苹果渣中高酯果胶的研究

以苹果渣为原料。对用微波辅助提取、提取液脱色、乙醇沉析获得果胶的关键提取条件进行了研究。通过L9（3^4）正交试验,得到了在微波辐射功率为250w时果胶提取的最佳工艺条件：料液比1：40,提取时间35min,pH=1．3,提取温度65℃,此时,果胶的提取率可以达到10．61％。效果很佳。     

正交试验法优选坛紫菜多糖的提取工艺

目的：对常规法提取紫菜多糖的工艺进行优化；方法：L16（4^4）正交试验及方差分析；结果：影响紫菜多糖热水提取的主要因素为醇沉浓度，其次是浸提时间，再次是浸提温度和料液比；结论：常规法提取紫菜多糖的优选方案为浸提温度80℃、浸提时间1．5h、料液比1：20、醇沉浓度90％。     

菊花绿茶复合饮料的研制

以绿茶、菊花为主要原料,研究了菊花茶饮料加工工艺中的最佳浸提方法和条件,确定了饮料的最佳调配比例。结果表明,采用微波辅助水浴法浸提得到的浸提液品质较常规水浴法的好,微波辅助水浴法浸提绿茶的最佳工艺条件为：茶水比1∶100、pH5、微波功率为400W条件下处理4min、90℃水浴锅中浸提10min;菊花浸提最佳工艺条件为：料水比1∶180、微波功率为175W条件下处理10min、80℃水浴锅中浸提15min。饮料最佳调配比例为绿茶汁40%、菊花汁50%、白砂糖2%、柠檬酸0.02%。     

超声波辅助提取茶鲜叶中茶多糖实验研究

本文研究了超声波辅助法提取茶树鲜叶中多糖的工艺。通过正交试验设计L9（3^4）提取多糖,以蒽酮-硫酸法测定多糖含量,得出优化工艺的条件为：固液比为1：10,浸提时间为60min、浸提温度为70℃、提取次数为3次,在此条件下茶粗多糖提取率为5．155％。     

黄精多糖脱色和脱蛋白工艺研究

目的:研究脱色和脱蛋白工艺中不同条件对黄精中多糖纯化效果的影响,得出黄精多糖的最佳脱色和脱蛋白工艺。方法:通过用双氧水和活性炭对黄精多糖进行脱色,在此基础上研究浓度差异对脱色效果的影响,确定最佳脱色工艺。采用Sevage法和TCA法对黄精多糖进行脱蛋白,研究不同条件对脱蛋白效果的影响。结果:双氧水法为黄精多糖的最佳脱色方法,其最佳脱色浓度为1%;Sevage法为黄精多糖的最佳脱蛋白方法,其最佳比例为氯仿:正丁醇为6:1。     

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