玉米淀粉生产高麦芽糖浆研究

首先研究了两种耐高温α-淀粉酶和两种真菌α-淀粉酶的酶学性质，确定了最佳酶制刑及反应条件。又以30％的玉米淀粉为原料，用耐高温α-淀粉酶N酶水解至DE值为16．5％，再用真菌α-淀粉酶B酶在最佳条件下作用21h，可得到含纯麦芽糖31．1％、葡萄糖1．7％、糊精2．7％的产品，质量达到国内同类产品的先进水平。     

大豆β-淀粉酶的制备及酶学性质的研究

研究了从大豆中提取β-淀粉酶的方法，大豆β-淀粉酶的酶学性质，并对提酶后的大豆蛋白进行制备酱油和分离大豆蛋白的研究。经工厂批量生产．成品酶制剂的活力达30OKu／g左右，收率平均为56％，经纸层析分析，酶系纯，是高麦芽糖浆工业理想的酶制剂。制备酱油的全氮利用率达80％，分离大豆蛋白的蛋白质含量达92％。     

耐高温α-淀粉酶的酶学性质研究

耐高温α-淀粉酶是淀粉生产麦芽糖的关键酶。本文对两种耐高温α-淀粉酶的酶学性质进行了对比研究。结果表明：两种酶的耐高温能力差别较大，酶活差别明显；最适pH值均为7．0，耐酸性较差：当Ca^2＋浓度在7～9mmol／L时，酶活提高明显。     

β-淀粉酶酶解甘薯淀粉条件分析

麦芽糖可以诱导枯草芽孢杆菌产生中温α-淀粉酶,甘薯淀粉的β-淀粉酶酶解产物主要为麦芽糖。应用高效液相色谱示差折光检测法对不同酶解条件下甘薯淀粉β-淀粉酶酶解产物进行分析。结果表明,液化酶加入量为5~10U/g干淀粉时,酶解产物中葡萄糖的含量最高可达0.94%±0.048%,其含量较低,不会对枯草芽孢杆菌产α-淀粉酶具有阻遏作用。酶解最佳条件为液化酶加入量5U/g干淀粉,β-淀粉酶最佳加入量为200U/g干淀粉,酶解最佳温度为60℃,最佳酶解时间为28h时,此条件下甘薯淀粉酶解产物中麦芽糖含量达75.8%±1.7%。甘薯淀粉β-淀粉酶酶解产物可以诱导β-淀粉酶酶解产物枯草芽孢杆菌发酵生产中温α-淀粉酶。研究对枯草芽孢杆菌发酵生产中温α-淀粉酶碳源优化具有重要意义。     

甲醛清洗对高粱麦芽酶形成的影响

研究三种高粱麦芽样品（Safmri，Madjeru，S．35），制麦前用0．1％（v／v）甲醛溶液清洗来评估成品麦芽的酿造潜力。甲醛清洗使样品中糖化类酶潜力下降。三种高粱品种发芽后期α-淀粉酶，β-淀粉酶，β-葡聚糖酶形成水平减少的幅度远高于样品发芽早期。α-淀粉酶形成水平，Safrari样品大约降低了22％；Madjem样品降低了52％；S．35样品降低了24％。β-淀粉酶形成水平，Safrari样品大约降低了32％；Madjem样品降低了57％；S．35样品降低了44％。β-葡聚糖酶形成水平，Safrari样品大约降低了34％；Madjeru样品降低了45％；S．35样品降低了66％。仅有Safrari和S．35麦芽的麦汁可以过滤。Safrari和S．35麦芽样品自由α-氨基氮（rAN）含量也分别减少了21％和27％，可发酵性糖的含量也相应较少，麦芽糖含量分别减少18％和19％。     

真菌α－淀粉酶饴糖的制造

真菌α－淀粉酶为内切酶，用它生产麦芽糖时，产品成分受很多因素影响。本文研究了淀粉乳浓度、液化淀粉葡萄糖值（ＤＥ值）、加酶量、反应时间以及脱支酶对真菌α－淀粉酶糖化的影响。实验发现，淀粉浓度、液化淀粉葡萄糖值对反应的影响较小，加酶量影响较大，酶量太少，即使延长反应时间，麦芽糖含量也很低。酶量过高，则会生成较多的葡萄糖。脱支酶有助于糖化，添加后麦芽糖含量增加６％左右。     

大豆β-淀粉酶在生产麦芽糖浆上的优势

介绍了β-淀粉酶和α-淀粉酶的酶种来源及其在生产麦芽糖浆中的作用机理,并对大豆β-淀粉酶、大麦β-淀粉酶、小麦β-淀粉酶、真菌α-淀粉酶、普鲁兰酶的适用条件、失活条件进行了比较,得出大豆β-淀粉酶在生产麦芽糖浆上的优势。     

α-淀粉酶发酵液絮凝的研究

研究了阳离子聚丙烯酰胺絮凝剂与硅藻土助滤剂配合施用对α-淀粉酶发酵液的絮凝处理工艺。结果表明：适宜的絮凝条件为pH7．0-7．5，温度30-35℃，阳离子聚丙烯酰胺用量0．4-0．5g／L，硅藻土用量20g／L。此时茵体絮凝率（FR）可达95％1；2上。α-淀粉酶发酵液经絮凝处理后，过滤速率（FV）为未处理的9．36倍，滤液澄清率（TR）在98％以上，α-淀粉酶活力回收率达92％以上。     

樟绒枝霉α-淀粉酶在毕赤酵母中的高效表达及在麦芽糖浆制备中的作用

从嗜热真菌樟绒枝霉(Malbranchea cinnamomea)中克隆α-淀粉酶基因McAmyA,并在毕赤酵母GS115中高效表达,经高密度发酵至168 h时,胞外酶活力达到13 440. 6 U/mL。重组α-淀粉酶McAmyA粗酶液经QSFF强阴离子交换层析纯化得到电泳级纯酶,比酶活力为1 230. 2 U/mg。酶学性质研究表明,重组α-淀粉酶McAmyA的最适pH和最适温度分别是6. 5和65℃。以淀粉液化液为底物,在温度60℃,加酶量120 U/g,水解24 h的条件下,重组α-淀粉酶McAmyA水解液化液,制备得到麦芽糖含量为50. 0%(质量分数)的麦芽糖浆。该真菌α-淀粉酶在毕赤酵母中表达水平高,具有很大的应用潜力。     

α-淀粉酶对甘薯果脯废糖液澄清效果的研究

本文研究了α-淀粉酶在甘薯果脯制作过程中对产生的废糖液进行澄清处理的效果，并通过正交试验确定了最佳工艺参数。结果显示，α-淀粉酶的最佳处理条件为：酶用量100U／mL，温度55℃，pH5．5，酶解时间为1h。此时糖液透光率可以达到83％以上。本研究旨在为甘薯果脯加工中糖渍液的废物利用提供技术支持。     

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.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.