蛋氨酸亚铁合成及性质研究（注）

以氨化亚铁和L-蛋氨酸（L-H11C5O2NS）为原料对食品铁强化剂蛋氨酸亚铁螯合物的合成进行了研究。确定合适的配合反应的条件为：以还原铁粉为抗氧化剂、n(H11C5O2NS):n(Fe)=2：1、PH=6.5、反应温度80℃、反应时间4h。采用有机溶剂沉淀处理并经重结晶纯化的方法得蛋氨酸亚铁螯合物产品，产品得率为68.1%。用元素分析、化学分析、质谱分析、红外和紫外光谱分析、X-射线衍射分析、电导分析等对所制产品进行了性质表征，确定了蛋氨酸亚铁螯合物的组成。     

微波固相合成蛋氨酸锌工艺的研究

微量元素氨基酸螯合物是近年来发展较快的一种新型营养添加剂。本实验以氯化锌和蛋氨酸为原料,利用微波固相的方式合成了蛋氨酸锌螯合物,确定了最佳反应条件为:配体摩尔比:2∶1,微波加热时间:240s,引发剂水添加量:12%,反应物粒度140目,碳酸钠添加量:20%。产品得率90.13%。经红外光谱分析和元素分析,确定蛋氨酸锌的组成为Zn(Met)2。     

食品营养强化剂蛋氨酸亚铁螯合物合成工艺研究

对食品营养强化剂蛋氨酸亚铁螯合物的合成工艺条件进行了初步研究,重点研究了配体摩尔比和ｐＨ值对配合反应的影响,确定合适的配合反应的条件为配位体摩尔比２：１,ｐＨ＝６．５,产品得率为９５．８％,产品中含Ｆｅ＾２＋１５．５４％,含Ｍｅｔ８２．７％确定了蛋氨酸铁螯合物的组成为Ｆｅ（Ｍｅｔ）。采用有机溶剂处理的方法,使蛋氨酸亚铁螯合物以沉淀方式析出,为其分离提纯和进一步研究提供了可能。为开发应用第三代铁的仪     

蛋氨酸亚铁合成及性质研究

以氯化亚铁和L -蛋氨酸 (L -H1 1 C5O2 NS)为原料对食品铁强化剂蛋氨酸亚铁螯合物的合成进行了研究。确定合适的配合反应的条件为 :以还原铁粉为抗氧化剂、n(H1 1 C5O2 NS)∶n(Fe) =2∶1、pH =6 .5、反应温度 80℃、反应时间 4h。采用有机溶剂沉淀处理并经重结晶纯化的方法得蛋氨酸亚铁螯合物产品 ,产品得率为6 8.1%。用元素分析、化学分析、质谱分析、红外和紫外光谱分析、X -射线衍射分析、电导分析等对所制产品进行了性质表征 ,确定了蛋氨酸亚铁螯合物的组成     

食品营养强化剂蛋氨酸亚铁螯合物合成研究

采用有机溶处理法测定了蛋氨酸亚铁螯合物的合成工艺。其合成工艺条件为配位体摩尔比２：１、ＰＨ＝６．５。此时产品得率为９５．８％，产品中含Ｆｅ＾２＋１４．８４％，ｗｙｎｋＭｅｔ７７．３６。     

微波固相合成蛋氨酸铜的初步研究

微量元素氨基酸螯合物是近年来发展较快的一种新型营养添加剂,具有良好的化学、生化稳定性及较高的生物学效价。本实验研究了以蛋氨酸和乙酸铜为原料,在固体状态下,通过微波辐射一步快速合成蛋氨酸铜螯合物,并对其工艺条件进行初步摸索。     

蛋氨酸对菜籽饼的解毒作用及其机理研究

饲喂含20％菜籽粕、添加0.65％蛋氨酸饲粮的生长猪比饲喂相同菜籽粕含量、不添加蛋氨酸饲粮组的生长猪日增重提高22％(P<0.05),蛋氨酸添加量提高到0.75％时,则日增重提高39％(P<0.05)。含20％菜籽粕饲粮中添加0.75％蛋氨酸组比不添加蛋氰酸组肝/胴体比降低21％(P>0.05),肾/胴体比降低42％(P<0.05),血清GPT水平降低27％(P<0.05),均与对照组差异不显著(P<0.05);此外,添加蛋氨酸消除了菜籽粕引起的肝、肾组织病理学变化。在含20％菜籽粕饲粮中添加0.75％蛋氨酸,猪血清硫肾酸盐水平比不添加蛋氨酸的对照组升高35％(P<0.05),提示蛋氨酸的解毒机制可能是将引起肝、肾病变的腈化物转化为对肝、肾无明显影响的硫氰酸盐。     

卵黄高磷蛋白肽-亚铁螯合物的制备及其稳定性分析

目的 优化卵黄高磷蛋白肽螯合亚铁的制备工艺，筛选结合亚铁含量最高的卵黄高磷蛋白肽制备肽-亚铁螯合物，并分析该螯合物的耐温、耐盐、耐酸碱稳定性。方法 响应面法优化亚铁螯合物的制备工艺，超滤分离得到不同分子量大小的肽组分，采用邻菲罗啉法测定亚铁结合含量，采用Ferrozine法测定温度、盐浓度、pH对游离铁释放量的影响。结果 最优螯合工艺条件为肽-亚铁质量比4:1、63℃、pH 4.8、43 min，该条件下小于3 kDa卵黄高磷蛋白肽的亚铁结合含量最高，为(96.13±2.86) μg Fe2+?mg pro，该螯合物耐温、耐盐、耐酸碱稳定性较好。结论 优化工艺的亚铁螯合率高，既能够节约亚铁离子的用量，还能够提高肽-亚铁的结合含量。小于3 kDa卵黄高磷蛋白肽-亚铁螯合物的亚铁含量高、稳定性好，是一种潜在的铁补充剂。 关键词：卵黄高磷蛋白肽；肽-亚铁螯合物；稳定性     

蛋氨酸在面包中应用研究

通过添加不同量蛋氨酸研究其对面粉粉质拉伸特性及对面包焙烤品质和贮存过程中老化程度影响。结果表明:蛋氨酸可改善面团流变特性,适量添加可增加面包体积和比容,改善面包芯硬度和组织结构,对增加面包蛋白质含量和持水能力、提高面包营养和感观品质有促进作用,同时能有效延缓面包老化,延长其货架期;蛋氨酸最适添加量为0．15％。     

多肽亚铁螯合物制备及抑菌活性研究

以舟山带鱼下脚料为原料,制备多肽亚铁螯合物,并研究亚铁鳌合物的抑菌活性。利用风味酶和动物复合蛋白酶双酶法制备水解液,采用氯化亚铁螯合。以大肠杆菌、金黄色葡萄球菌等为测试菌株,采用牛津杯双层平板法确定亚铁螯合物的抑菌中浓度及探讨pH和温度对亚铁螯合物抑菌活性的影响。结果表明：（1）最佳酶解条件为带鱼下脚料蛋白用量4．1g/100mL,温度40℃,复合比1：1,酶量6&#215;10^3 IU／100mL,pH7;（2）带鱼下脚料蛋白最佳螯合条件为：pH7,时间15min,温度20℃,抗坏血酸用量0．1％;（3）抑菌活性试验结果表明：亚铁螯合物对所选取的测试菌株除普通变形杆菌外都有一定抑菌作用,其中对巨大芽胞杆菌抑菌效果最好;在酸性条件下抑菌活性仍然较高,但在碱性环境中抑菌活性明显降低;在较低温度下保持抑菌活性,但高温处理后抑菌活性显著降低。亚铁螯合物对各测试菌株除普通变形杆菌之外均有较强的抑菌活性,是一种对细菌较为广谱的抑菌剂。     

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.