微波辅助提取苦参总黄酮

研究苦参中黄酮类化合物的微波提取最佳工艺。采用单因子及正交实验，考察了乙醇浓度、微波时间、微波功率及固液比对苦参黄酮类化合物提取量的影响规律。结果：苦参黄酮类化合物提取工艺的最佳参数组合为：乙醇体积分数10％，微波作用时间6min，功率为420w，固液比为1：25（g／mL）。在最佳参数组合下苦参中总黄酮的提取量可达4．83％。结论：采用微波技术提取苦参中总黄酮具有良好的应用前景。     

苦参中黄酮类组分的提取及抗氧化性的研究

用正交试验探索超临界萃取苦参中黄酮类组分的最佳工艺条件,最佳参数为:温度40℃,压力30 MPa,乙醇流速0.4 mL/min,时间60 min,最高得率为5.82%.在此基础上对苦参中黄酮类组分进行分离提取,用分光光度法测定其抗氧化性.结果显示苦参中黄酮类组分对自由基有消除作用.     

大果沙枣果肉中总黄酮的提取工艺研究

为研究大果沙枣果肉中总黄酮的最佳提取工艺,采用超声辅助提取法,以乙醇为溶剂,总黄酮提取率为考察指标,通过单因素试验和正交试验研究乙醇浓度,提取时间,提取次数和提取温度对总黄酮提取率的影响。结果表明,影响大果沙枣果肉中总黄酮提取率的主要因素是提取温度,其次是乙醇浓度、提取次数和提取时间。最佳提取工艺为:乙醇浓度40%vol,时间30min,提取次数3次,提取温度70℃。并在该条件下测得大果沙枣果肉中黄酮类化合物的含量分别为0.643%。     

超声波辅助法提取山黄皮果仁中的总黄酮

目的:确定山黄皮果仁中总黄酮最佳提取工艺。方法:采用超声波辅助法提取山黄皮果仁中的黄酮类化合物,通过单因素实验和正交实验,考察超声波提取条件(乙醇浓度、料液比、超声波功率、提取温度及超声波提取时间)对山黄皮果仁总黄酮提取率的影响。结果:山黄皮果仁总黄酮提取最佳工艺为:温度50℃,60%乙醇,料液比1:35,超声功率70 W,提取时间30 min。结论:在此工艺条件下提取,总黄酮提取率为1.159%。     

超声波辅助法提取苹果渣中总黄酮的研究

研究利用超声波提取苹果渣中黄酮类化合物的工艺.通过单因素试验考察乙醇浓度、超声渡功率、提取温度、处理时间、料液比和浸泡时间对总黄酮提取率的影响.在单因素试验的基础上,利用正交试验确定超声波法提取苹果渣中总黄酮类化合物的最佳工艺条件:80%乙醇,超声波作用时间30 min,超声波功率480W,液料比1:40(g/mL),浸泡时间24h,超声波温度70℃,提取2次,总黄酮提取率为7.42mg/g.     

表面活性剂协同超声波提取合欢花中黄酮类化合物

采用超声波协同表面活性剂法提取合欢花中黄酮类化合物,以总黄酮提取率为指标,考察表面活性剂种类及浓度、固液比、提取温度、超声时间对提取合欢花中黄酮类化合物的影响,并经正交试验进一步优化工艺参数。结果表明:最佳工艺条件为表面活性剂选择0.8%十二苯磺酸钠(SDBS),固液比1∶40(g∶m L),提取温度40℃,超声时间30min。与其他提取方法相比,SDBS具有很好的协同作用,具有节能省时、提取率高等优点,最佳提取率为2.55(n=3,RSD=1.61%)。     

梓树果实中黄酮类化合物提取工艺研究

以梓树果实为原料,对黄酮类化合物提取工艺进行研究,采用单因素试验法对影响梓树果实中黄酮类化合物提取率的主要因素进行了分析,利用正交试验优化了提取总黄酮的最佳工艺条件.研究表明,梓树果实中提取黄酮类化合物的最佳条件为:乙醇浓度60%,提取温度70"C,料液比1:20,提取时间2.Oh,在最佳条件下总黄酮的提取率为4.83%.     

槲寄生中黄酮类化合物不同提取工艺的研究

采用超临界C02萃取、回流提取、超声波辅助浸提三种方法提取槲寄生中的黄酮类化合物。结果表明，超声波辅助浸提法总黄酮提取率优于超临界C02萃取法和传统的溶剂回流提取。通过正交试验，得到最佳工艺条件为乙醇体积分数80％，超声时间15rain，溶剂用量40ml／g，此条件下总黄酮的提取率为1．37％。     

八角和八角残渣总黄酮提取工艺优化

目的：确定八角和八角残渣中总黄酮的最佳提取工艺。方法：采用乙醇热回流法提取八角和八角残渣中的黄酮类化合物,通过单因素试验和正交试验,考察乙醇体积分数、料液比、提取时间、提取次数对八角和八角残渣中总黄酮提取率的影响。结果：八角总黄酮提取最佳条件为：80% 乙醇、料液比1:30、提取时间120min、提取次数3 次。八角残渣总黄酮最佳提取条件为：乙醇体积分数50%、料液比为1:10、提取时间120min、提取次数3 次。结论：在最佳工艺条件下,八角总黄酮提取率为23.61%,八角残渣总黄酮提取率为16.81%。     

超高压提取葡萄籽总黄酮的研究

利用超高压技术提取葡萄籽中黄酮类化合物。在单因素实验的基础上,采用正交实验法对葡萄籽中黄酮类化合物的超高压提取工艺进行优化,以总黄酮的提取率为指标,用分光光度法测定其含量。得到最佳工艺条件为:乙醇体积分数75%、提取压力325MPa、保压时间6min、提取温度50℃、料液比1:35(g/mL),优选结果经验证实验,获得较高得率为7.29%。     

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.