栀子蓝色素的分步制备工艺

优化栀子蓝色素分步制备的工艺。以栀子黄生产废液提取物——京尼平苷为底物原料,以黑曲霉发酵制备的β-葡萄糖苷酶为转色酶,研究京尼平苷水解制备京尼平的影响因素,通过正交设计试验优化其工艺条件。以显色生成亮丽栀子蓝色素为目标,筛选显色氨基酸,制备色泽明亮的栀子蓝色素。结果表明,在添加8%粗β-葡萄糖苷酶量,反应温度55℃,p H 4.2,水解时间7 h条件下,京尼平产量最高;甲硫氨酸、甘氨酸、赖氨酸、丙氨酸等多种氨基酸均与京尼平反应生成蓝色素,其中甲硫氨酸显色反应生成物色泽亮丽,是由栀子蓝色素制备的适宜氨基酸;n_(甲硫氨酸)∶n_(京尼平苷)=6∶1、p H 7.0、显色温度80℃、时间10 h时,获得色泽明亮的栀子蓝色素,其色价为20.6。     

共固定化酶催化栀子苷水解制备栀子蓝色素

采用黑曲霉发酵产β-葡萄糖苷酶,再用戊二醛交联,海藻酸钠包埋法共固定化酶和菌丝,然后将共固定化酶用于水解栀子苷,再与谷氨酸钠反应制备栀子蓝色素。对共固定化条件进行了优化,优化后的条件为:交联剂戊二醛浓度为0.15%,交联温度为20℃,交联时间为2h。同时还对共固定化酶水解栀子苷的条件进行了优化,优化后的水解条件为:水解温度为50℃,水解时间为6h,水解pH为5.0。水解后的转化液与谷氨酸钠反应得到栀子蓝色素溶液,经大孔树脂HPD300吸附洗脱,洗脱液经真空减压浓缩、干燥后得栀子蓝色素粉末,色价E590nm1%为120。共固定化酶水解栀子苷制备栀子蓝色素的工艺与传统方法相比具有成本低、环境友好、易于工业化放大的特点。     

产β-葡萄糖苷酶菌株的筛选及发酵栀子蓝色素的研究

利用京尼平与谷氨酸的显色反应从自然界筛选到一株产β-葡萄糖苷酶的细菌菌株，并将该菌株应用于栀子蓝色素的发酵试验，试验结果表明，该细菌菌株发酵栀子蓝色素的最佳温度为37℃，发酵液pH为6．5，发酵时间为40h。     

栀子红色素转化菌的筛选及其固态转化条件的优化

研究以土壤筛选到的一株高产β-葡萄糖苷酶菌株作为固体发酵产酶菌株;对两步法转栀子红色素的工艺条件进行了优化;实验结果表明:向浓缩后的栀子苷废液(稀释400倍,A238=0.603)中添加12.5%的氢氧化钠,50℃磁力搅拌加热3h,添加31.25%柠檬酸,搅拌至柠檬酸完全溶解,4℃冷藏备用;固态发酵产物用去离子水按料液比1∶10,在45℃下浸提2h后用4层纱布过滤,滤液经3层滤纸抽滤,收集上清液,上清液即为粗酶液。50mL粗酶液中添加20mL预处理好的栀子苷后添加2g谷氨酸钠,45℃真空保温28h,然后将转化液沸水浴灭酶3h,此条件下转化生成的栀子红色素溶液稀释60倍在527nm波长下的吸光度为0.588;色价为212,是优化前的1.97倍。     

高色价栀子蓝色素的制备及其纯化工艺研究

以栀子黄废液中的栀子苷为原料,采用酶促反应制得栀子蓝色素,并利用壳聚糖衍生物作为层析柱填料对其进行精制纯化.通过正交实验确定了最佳的酶促反应工艺条件为:浓度为40%的栀子苷溶液100mL,反应温度50℃,反应时间50h,β-葡萄糖苷酶3mL,甘氨酸10g.层析法精制纯化的工艺务件为:层析柱径长比是1:20,上样量/填料比为1:40,蒸馏水作为洗脱剂,洗脱速度为0.1mL/s.精制得到的栀子蓝色素粉末的色价(E1cm 1%)为238,OD值为0.24,达到了国际市场标准.     

嗜酸乳杆菌GIM1.208产β-葡萄糖苷酶培养基及发酵条件优化

以嗜酸乳杆菌（Lactobacillus acidophilus）GIM1.208为研究对象,通过单因素、正交试验和响应面法优化其产β-葡萄糖苷酶的培养基及发酵条件。结果表明,嗜酸乳杆菌GIM1.208发酵产β-葡萄糖苷酶的最佳产酶条件为葡萄糖添加量3.0%,羧甲基纤维素钠添加量0.4%,初始pH值5.5,料液比1∶4（g∶mL）、发酵温度31 ℃,发酵时间24 h,接种量2.6%。在此优化条件下,β-葡萄糖苷酶活力为16.80 U/mL,是优化前的3.90倍。     

发酵酶解耦合法大豆苷元转化工艺

以市售大豆异黄酮粉为样品,选用产β-葡萄糖苷酶的LJ-Q2菌种与优化后的固定化β-葡萄糖苷酶进行耦合发酵,采用单因素、响应曲面法对耦合发酵条件进行优化,高效液相法(HPLC)测定大豆异黄酮苷元,考察耦合发酵条件对大豆苷元转化率的影响。研究结果如下:最优条件为温度54℃,耦合时间3 h,初始p H7,固定化酶添加量7%;大豆异黄酮苷元绝对质量13.76 mg,大豆异黄酮苷元转化率为76.8%。对大豆苷制备应用技术开发有参考价值。     

响应面法优化栀子黄废液制备栀子蓝色素酶解工艺的研究

本实验以栀子黄浓缩废液为原料,栀子蓝色素色价为指标,通过酶种类、酶解时间、酶添加量、酶解pH单因素及响应面优化实验,制备高色价栀子蓝色素。实验结果表明:酶解栀子黄浓缩废液最适酶为纤维素酶,酶解pH为5.2,酶添加量为2.0%,酶解时间6.5 h,酶解温度55℃。在此酶解工艺条件下,酶解液中加入1%的组氨酸,80℃水浴5h,烘干后栀子蓝色素色价可达33.6。该工艺操作简单、成本低、栀子蓝色价高,可广泛应用于实际生产过程中。     

大豆异黄酮水解物的制备

利用黑曲霉产酶发酵培养基制备β-葡萄糖苷酶,再利用β-葡萄糖苷酶水解大豆异黄酮粉制备异黄酮苷元。研究结果表明,较优产酶发酵培养基的C/N为6∶4,加水量1.4倍,培养基中不添加诱导物。水解500 mg40%大豆异黄酮粉的最佳条件为:加酶量100 U,水解温度50℃,水解时间1 h。     

酶法提取刺五加干果花色苷工艺优化及其组成分析

目的 优化刺五加花色苷的提取条件,并对该花色苷的组成进行分析。方法 通过单因素实验研究酶的种类、液料比、酶添加量、酶解温度和酶解时间对提取液中花色苷含量的影响,利用响应面试验优化了刺五加果花色苷的提取工艺。并利用超高效液相色谱串联三重四级杆飞行时间质谱（UPLC-Triple-TOF/MS）对刺五加花色苷进行结构鉴定。结果 刺五加果花色苷提取的最佳工艺条件为：液料比18︰1 mL/g,果胶酶的添加量4.2‰,酶解温度55 ℃,酶解时间3.0 h,在此条件下刺五加果的花色苷含量达到6.00 mg/g。经过UPLC-Triple-TOF/MS分析其中主要花色苷为矢车菊素3-O-(2-O-β-D-吡喃木糖基)-β-D-吡喃葡萄糖苷。结论 利用果胶酶法来制备刺五加花色苷是可行的,所得刺五加花色苷为矢车菊素3-O-(2-O-β-D-吡喃木糖基)-β-D-吡喃葡萄糖苷。     

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.