响应曲面法优化微波提取辣椒红色素的工艺

通过响应曲面法优化微波提取干红辣椒中辣椒红色素的工艺条件.以辣椒红色素的色价为考察指标,运用SAS软件得到微波提取的最佳工艺条件为:超声功率616W,提取温度40℃,提取时间10min,乙醇体积分数100%vol,料液比1:7(g:mL),物料粒径40目,在此试验条件下辣椒红色素的色价达109.17.     

红花红色素的超声提取研究

本文对红花红色素的超声提取方法进行了研究,通过单因素试验和正交设计试验确定超声提取红花红色素的影响因素并筛选其优化提取条件,采用分光光度法测定其含量,并用色价来衡量.实验结果表明,提取红花红色素的最佳溶剂为70 %丙酮,其最佳提取条件为:超声时间30 min,提取两次(30 min,30 min),超声温度40 ℃,固液比1:12(m/v).     

超声波提取辣椒红色素的工艺研究

研究超声提取辣椒红色素的工艺,通过正交试验得出超声提取辣椒红色素的最佳工艺条件,即以无水乙醇为提取溶剂,超声功率为240W,料液比1：15,超声时间为20min,辣椒红色素得率可高达1．573％。     

响应面优化超声辅助酶法提取辣椒红色素研究

以铁皮辣椒为原料,在单因素实验的基础上,选择超声功率、乙醇浓度、超声时间、酶用量进行四因素三水平的Box-Benhnken实验,利用Design-Expert 8.0软件进行响应面分析。响应面法优化结果表明,在超声功率434 W、乙醇浓度75.5%、超声时间76.3 min、酶用量4 mg的条件下,辣椒红色素的提取效果最佳。该研究为辣椒红色素的提取提供了实验参考,为辣椒红色素作为食品色素添加剂提供了参考。     

超声波辅助浸提甜菜红色素的工艺研究

利用超声辅助乙醇浸提法萃取技术,优化甜菜中红色素提取工艺参数。以单因素试验为基础,采用正交实验优化提取甜菜红色素工艺,确定最佳提取条件为:浸提液乙醇浓度40%,pH值5.5,料液比1∶10,超声波功率90%W(占总功率),提取温度40℃,提取时间40 min。     

响应面法优化辣椒红色素超声波－微波协同提取工艺

辣椒红色素是一种天然色素,因其具有色泽鲜艳、无毒副作用等优点被广泛应用到食品加工、化妆品和医药等行业。本文以95％乙醇为提取剂,利用超声协同微波的方法提取辣椒红色素。研究提取温度、提取时间、料液比、乙醇浓度、超声提取时间、微波时间等因素对辣椒红色素提取率的影响。在单因素实验的基础上,利用中心组合实验设计对辣椒红色素提取工艺进行优化,采用3因素3水平实验设计,依据回归分析确定工艺影响因子,以辣椒红色素提取率为响应值作响应面和等高线,在分析各个因素的显著性和交互作用后,得出最佳提取工艺条件：料液比1:23,超声波时间21min,微波时间11min,提取2次。在此条件下,吸光度（得率）最高可达0.626。     

鸢尾科红葱红色素的提取及抗氧化活性评价

在单因素试验的基础上,采用二次回归正交旋转组合试验对超声辅助提取鸢尾科红葱红色素的工艺条件进行优化,并对红葱红色素粗提物的体外抗氧化活性进行评价。结果表明,红葱红色素最优提取工艺条件为:乙醇体积分数31%,料液比1∶54(g/mL),超声时间40 min;在此条件下,红葱红色素粗提物得率为17.97%。红葱红色素粗提物具有一定的还原能力、DPPH自由基清除能力和羟自由基清除能力,其清除效果与市售红曲红色素接近,清除能力与浓度之间呈现一定的量效关系。     

有机溶剂萃取法提取辣椒红色素的研究

探索有机溶剂法从干红辣椒中提取辣椒红色素的工艺条件,以获得高色价的辣椒红色素.考察了丙酮、95％乙醇、正己烷、乙酸乙酯、石油醚等有机溶剂对辣椒红色素提取的影响,结果表明:正己烷为最佳的提取溶剂.通过单因素实验和正交实验确定正己烷提取的最优条件:提取温度为60℃,萃取次数2次,每次萃取时间为110 min,液料比35(mL/g),萃取色素相对量达18.01％.     

响应面法优化红干椒中辣椒红色素提取工艺

采用超声波法快速提取红干椒中的辣椒红色素,在确定样本容量的基础上,考察了超声温度、超声时间和超声功率对测定结果的影响,采用响应面分析法确定了最佳提取条件.结果表明:采用超声波法提取辣椒红色素时,辣椒取样量为15个,辣椒粉末取样量为1.000 g,超声温度48℃,提取时间23 min,提取功率40 W.采用此方法处理样品时,缩短了提取时间,简化了测定步骤,所得数据重复性好,易于同时测定大批量样品中的辣椒红色素含量.     

响应面法优化脂质体包埋辣椒红色素的研究

辣椒红色素是一种天然食用色素,有着安全、营养价值高的优点,但较差的稳定性限制了它在食品中的应用。利用脂质体技术包埋辣椒红色素可以提高它的稳定性。研究了辣椒红色素脂质体的制备过程中影响包封率的几个因素,并通过响应面分析方法优化了制备条件。结果表明:脂药比(卵磷脂∶辣椒红色素)、超声时间和有机溶剂加入量是影响包封率的主要因素,其中脂药比和超声时间影响显著。包封率较高的工艺条件为:脂药比22∶1(卵磷脂0.44g,辣椒红色素0.02g)、胆固醇0.03g、超声时间12min、有机溶剂加入量为25mL(氯仿/甲醇=2∶1,v/v)。在此条件下脂质体包封率为98.98%,误差0.16%,重复性较好。     

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.     

Focus on China's Paper Industry

In the English section of this issue, 〈China Paper Newsletters〉 will introduce ＂National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the ＇13th Five-Year Plan＇＂, ＂2013 Annual Report of China＇s Paper Industry＂, and news of projects and other policies.     

Listen to downstream & search for innovation

正Nowadays,textile enterprises are all taking efforts in transformation and upgrading,like improving producing capacity and optimizing production structure to face market downturn.It claimed a higher request to the standard of textile equipments.In the upcoming of ITMA ASIA+CITME 2014exhibition,this magazine have interviewed several branch associations and a series of relative enterprises,to summarize industrial developing status