纤维素酶法提取花生红衣中的白藜芦醇

目的:研究纤维素酶解法提取花生红衣中白藜芦醇的工艺条件.方法:在单因素试验基础上,采用L9(34)正交试验法对花生红衣白藜芦醇的酶法提取工艺进行优选.以白藜芦醇的得率为参考指标,考察酶用量、酶解温度、酶解时间、酶解pH值和乙醇浓度对花生红表白藜芦醇得率的影响.结果:最佳工艺条件为:纤维素酶与花生红衣粗粉的配比为1:500,酶解温度50℃,酶解pH 5.0,酶解时间90 min,提取溶剂乙醇的体积分数为60%.在此条件下白藜芦醇的得率为1.25%.与传统醇提工艺相比,其提取率提高了4.43倍.结论:该工艺是纤维素酶法提取花生红衣白藜芦醇的最佳工艺.     

响应面法优化超声辅助提取花生红衣多酚工艺

以花生红衣为原料,采用超声波辅助提取其中的多酚类物质。通过单因素试验对超声时间、超声功率、料液比、乙醇体积分数等工艺参数进行研究,并用响应面法优化提取工艺,建立二次多项数学模型。结果表明,花生红衣多酚提取的最佳工艺参数为超声时间24.4min、超声功率408W、料液比1:29.6(g/mL)、乙醇体积分数51%。结合实际操作,响应面优化的最优工艺参数调整为超声时间24min、超声功率410W、料液比1:30(g/mL)、乙醇体积分数51%,此条件下花生红衣多酚得率为8.95%。     

优化超声波辅助提取花生红衣中白藜芦醇的工艺

为优化超声波提取花生红衣中白藜芦醇的提取工艺,在单因素试验基础上,采用Box-Behnken试验设计分析得出了提取温度、液料比值及提取时间对花生红衣中白藜芦醇的得率有较大的影响,并以白藜芦醇的得率为响应值,得到其最佳提取工艺为:液料比值14.96 m L/g,提取时间63.60 min,提取温度49.56℃,溶剂体积分数75%,与模型预测值相符合。     

超声辅助提取花生红衣中原花青素

为探究花生红衣中原花青素的提取效果,在超声辅助提取的基础上,结合水浴浸提以提高提取效果,并利用正交试验对工艺进行优化。结果表明,各因素影响原花青素提取效果的主次顺序为：超声时间＞乙醇体积分数＞料液比＞超声温度;提取最佳条件为：超声时间15 min、乙醇体积分数60%、料液比1∶45（g/mL）、超声温度35℃、水浴温度50℃、水浴时间50 min,在此条件下原花青素提取率为9.07%。     

花生红衣中总黄酮的提取工艺

研究花生红衣中总黄酮的最佳提取工艺条件.以黄酮得率为指标,采用正交试验法考察乙醇浓度、料液比、提取时间、提取温度等4个因素对提取效果的影响.花生红衣中总黄酮提取最佳工艺为:80%的乙醇,料液比为1:15.提取时间为30min,提取温度为40℃,提取得率为1.242mg/100 g.此最佳工艺可用于花生红衣中总黄酮的提取.     

超声辅助法制备花生红衣的多酚类物质

在乙醇提取、微波辅助提取、超声辅助提取和酶辅助提取中筛选出超声辅助提取为花生红衣多酚类物质的最佳制备方法。在单因素试验的基础上,研究乙醇体积分数、提取时间、超声功率和提取温度4个主要因素对多酚类物质提取率的影响,通过二次旋转回归设计试验确定最佳提取工艺。试验结果表明,花生红衣多酚类物质的最佳提取工艺参数为:乙醇体积分数55%、提取时间13 min、超声功率240 W、提取温度47℃。在此条件下花生红衣多酚类物质的提取率达(85.62±0.52)%,与预测值基本相符。研究了不同干燥方式对提取物多酚含量和抗氧化活性的影响,结果冷冻干燥是花生红衣多酚类物质的最佳干燥方式。     

响应面法优化酶法制备花生蛋白的工艺研究

以花生粕为原料,对在乙醇水溶液中利用α-淀粉酶制备花生蛋白的工艺条件进行了研究。探讨乙醇体积分数、加酶量、pH、酶解温度、酶解时间、液料比6个因素对可溶性总糖提取率的影响,试验表明乙醇体积分数、酶解时间、pH和液料比对提取过程影响较大。通过Box-Behnken中心组合试验和响应曲面分析法优化工艺条件:pH 5.95、酶解时间52 min、液料比13.8∶1、乙醇体积分数76%、加酶量0.5%、酶解温度35℃,总糖提取率为13.06%。对此工艺条件进行验证得到蛋白质纯度为70.29%,而单纯的乙醇溶液提取法蛋白质纯度为62.03%。     

响应面法优化花生红衣原花青素微波辅助提取工艺

以花生红衣为原料,通过单因素试验,研究了乙醇体积分数、微波功率、微波处理时间、料液比对微波辅助提取花生红衣原花青素的影响,并在单因素试验基础上,设计三因素三水平的响应面分析方法对微波提取原花青素工艺进行优化,建立了二次多项式回归方程的预测模型,结果表明:微波辅助提取花生壳原花青素最佳参数为花生红衣粒度80目(0.198 mm),料液比1 g∶40 mL,乙醇体积分数75%,微波提取时间120s,微波功率240 W,在此条件下花生红衣原花青素得率为11.38%。     

花生种衣活性成分提取工艺参数优化

花生种衣富含黄酮类化合物、原花色素和白藜芦醇等多酚活性物质.本研究以花生种衣为原料,通过单因素试验考察乙醇浓度、水浴温度、提取时间和料液比对花生种衣中多酚物质提取效果影响,并通过响应面法对提取多酚工艺加以优化;结果表明,提取多酚最佳工艺条件为:乙醇体积分数55％、料液比1:20、水浴温度60℃、提取时间2h,在此条件下...     

花生衣红色素微波提取工艺研究

以花生红衣为原料,乙醇为浸提溶剂,利用微波技术提取花生衣红色素.通过单因素试验和正交试验,考察料液比、微波火力、浸提时间和乙醇体积分数等对花生衣红色素提取率和色价的影响.结果表明,微波法提取花生衣红色素的最佳工艺条件为:微波加热火力40,浸提时间60 s,乙醇体积分数50%,料液比1:25.在此工艺条件下,花生衣红色素的提取率为14.038%,色价为24.294.     

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.