超临界CO2流体萃取法在玉米蛋白前处理的应用

玉米蛋白粉是玉米湿法加工淀粉时的主要副产物。采用超临界CO2流体萃取技术对玉米蛋白进行脱脂脱异杂味前处理,研究了温度、压力、时间和CO2流量等主要因素对提取率的影响,通过正交试验法筛选出最佳参数。结果表明,其最佳条件为萃取压力30MPa,萃取温度50℃,萃取时间60min,CO2流量23L/h,萃取率达8.06%。     

蚕蛹油超临界二氧化碳萃取研究

以蚕蛹为原料,采用正交试验,研究萃取温度、萃取时间、萃取压力等因素对超临界CO2萃取蚕蛹油影响。确定蚕蛹油超临界CO2萃取条件,即萃取温度35℃,萃取时间2h,萃取压力25MPa。     

超临界CO2流体萃取法在玉米蛋白前处理的应用

玉米蛋白粉是玉米湿法加工淀粉时的主要副产物。采用超临界CO2流体萃取技术对玉米蛋白进行脱脂脱异杂味前处理，研究了温度、压力、时间和CO2流量等主要因素对提取率的影响．通过正交试验法筛选出最佳参数，结果表明，其最佳条件为萃取压力30MPa，萃取温度50℃，萃取时间60min，CO2流量23L／h，萃取率达8．06％。     

超临界CO2萃取杭白菊挥发油的工艺研究

采用超临界CO2 技术萃取杭白菊挥发油,以杭白菊挥发油得率为指标,采用正交试验考察萃取温度、萃取压力、CO2 流量、萃取时间4 个因素对杭白菊挥发油的超临界CO2 流体萃取的影响。结果表明萃取压力20MPa、萃取温度55℃、CO2 流量10kg/h 的条件下萃取2h 为最佳工艺,杭白菊挥发油得率达5.92%。     

超临界二氧化碳萃取薏苡仁油的研究

本文应用超临界CO2萃取技术萃取薏苡中的薏苡仁油, 考察了压力、温度、萃取时间、原料颗粒直径及CO2流体流量对萃取的影响.通过实验确定了超临界二氧化碳萃取薏苡仁油的较佳工艺条件为萃取压力33MPa,萃取温度42℃,物料粒度30目,萃取时间3h,CO2流体流量10㎏/h.     

超临界二氧化碳萃取孜然油工艺技术研究

利用超临界CO2萃取技术提取孜然油.研究了原料粒度、萃取压力、萃取温度、二氧化碳流量等因素在不同萃取时间下对孜然油萃取率的影响,以此为基础进行正交实验设计,确定超临界二氧化碳萃取最佳工艺参数.结果表明:超临界CO2萃取孜然油的适宜工艺参数为萃取时间2.0h、萃取压力为35MPa、萃取温度40℃、原料粉碎度40目、CO2流量25kg/h,分离压力6MPa,分离温度50℃.在此条件下,孜然油提取率达到13.56%.     

葡萄籽油超临界流体萃取工艺

研究了温度、压力、时间、CO2体积流量对超临界流体萃取葡萄籽油得率的影响,并进行了最佳工艺优化.结果表明,影响CO2流体萃取葡萄皮精油效率因素的主次作用为萃取时间＞萃取压力＞萃取温度＞CO2体积流量,最佳工艺条件为萃取时间4 h、萃取温度45 ℃、CO2体积流量8 L/h、萃取压力30 MPa.葡萄籽油出油率为14.8%.     

超临界流体萃取菊花油工艺

研究温度、压力、时间、CO2流量对超临界流体萃取菊花油得率的影响,并进行最佳工艺优化.结果表明,影响CO2流体萃取菊花油效率因素的主次作用为萃取时间>萃取温度>萃取压力>CO2流量,最佳工艺为:萃取压力30MPa、萃取温度45℃、CO2流量8 kg/h、萃取时间4 h,菊花油出油率为1.05%.     

十三香精油提取工艺研究

采用超临界CO2萃取技术提取十三香精油,通过单因素试验研究了CO2流量、萃取时间、萃取压力和萃取温度对精油得率的影响,正交试验确定了超临界CO2萃取十三香精油的最佳条件:CO2流量20 L/h、萃取时间2.5h、萃取压力27 MPa和萃取温度40℃.研究结果为十三香精油的提取工艺提供了技术参数,可应用于工业化生产.     

超临界二氧化碳萃取沉香精油的工艺优化

应用超临界CO2萃取技术提取国产沉香木中的沉香精油。考察了浸泡时间、萃取压力、温度、料液比、萃取时间对沉香精油萃取率的影响,并通过响应面实验确定了超临界CO2萃取沉香精油的最佳工艺条件为:浸泡时间83h,萃取压力28MPa,温度46℃,料液比1∶1.2,萃取时间2h。在此条件下沉香精油萃取率为1.89%。     

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