复凝聚法制备橄榄油微胶囊

目的:优选以乳清蛋白和阿拉伯胶为壁材的橄榄油微胶囊最佳工艺。方法:通过壁材凝聚率选出最佳壁材配比及最适浓度,采用复凝聚法制备微胶囊。首先对壁芯比、复凝聚pH、凝聚时间做单因素试验,然后通过响应面试验筛选制备微胶囊的最佳工艺。结果:在壁材质量分数3%、壁芯比3、pH 4、凝聚60 min条件下制备微胶囊,最高包埋率为87.95%,包埋效果较好。     

明胶-阿拉伯胶复凝聚法制备芥末油微胶囊

以明胶和阿拉伯胶为壁材,芥末油为芯材,采用复凝聚法制备球形多核微胶囊。研究壁材浓度、明胶与阿拉伯胶的比例、芯壁比、pH、反应温度和时间等因素对微胶囊成囊的影响。通过实验确定的最佳工艺参数:壁材浓度1%,明胶与阿拉伯胶的比例1∶1,芯壁比1∶1;复凝聚反应pH 3.4,温度40℃,时间20min。在此工艺条件下得到的微胶囊产品的包埋率为92.66%。     

乳脂微胶囊的制备

以乳脂包埋率为主要指标,采用单因素试验和响应面分析法研究壁材配比、芯壁比、固形物中乳化剂的添加量和固形物浓度对乳脂微胶囊化效果的影响,并确定了喷雾干燥法制备乳脂微胶囊产品的工艺条件。结果表明:乳脂微胶囊化的最佳配方为,壁材为乳清蛋白和麦芽糊精,二者质量比1∶2.6,芯壁质量比1∶3,乳化剂添加量为3%,固形物浓度为23.5%;喷雾干燥的最佳条件为,进风温度170℃,出风温度80℃,均质压力40 MPa,微胶囊化乳脂的包埋率93%以上。     

复凝聚法制备黄酮类化合物微胶囊研究

以明胶和CMC(羧甲基纤维素)为壁材,采用复凝聚法制备黄酮类化合物微胶囊。通过单因素和正交试验确定影响制备黄酮类化合物微胶囊主要因素,经实验确定最优工艺条件为:壁材浓度1.5%、明胶∶CMC为8∶1、芯壁比1∶5、复凝聚pH值4.6、复凝聚温度40℃;在此条件下,黄酮类化合物微胶囊平均包埋率可达78.2%。     

韭菜籽油微胶囊的制备及工艺优化

为提高韭菜籽油的资源利用率和产品附加值,本研究以韭菜籽油作为芯材,分别以明胶-阿拉伯胶、明胶-CMC、HI-CAP 100-明胶以及HI-CAP 100-麦芽糊精4种组合作为壁材,利用复凝聚法制备微胶囊,并对比冻干和喷雾干燥两种干燥方式对微胶囊的影响。以韭菜籽油微胶囊包埋率、光学显微镜和扫描电镜结构表征图为反应指标,在反应pH、壁材浓度、壁材比及芯壁比四种不同因素下,确定最佳组合壁材为HI-CAP 100-麦芽糊精,喷雾干燥制备得到的微胶囊性能优于冻干法。通过单因素实验和响应面优化分析,确定韭菜籽油微胶囊最佳优化工艺条件：反应pH为4.56,壁材比为1.07：1,芯壁比为1.28：1,壁材浓度为1.04%,在此条件下微胶囊包埋率可达90.80%。该研究为韭菜籽油的高值化利用提供了理论依据。     

明胶/CMC复合凝聚法制备微胶囊研究

以明胶和CMC(羧甲基纤维素钠)为壁材,肉桂醛为芯材,通过复合凝聚法制备球形多核微胶囊.研究明胶/CMC比例、pH、壁材浓度、芯壁比等参数对胶囊形态、粒径及包埋效果的影响.试验确定最佳工艺参数为:明胶/CMC比例9∶1, pH 4.6～4.7,壁材浓度1%,芯壁比2∶1.在此条件下制备的微胶囊球形较好,表面光滑,粒径均一.与明胶/阿拉伯胶制备的微胶囊相比,形态相似,产率较高,而壁材成本大大降低.     

苦瓜籽油的复凝聚微胶囊化技术研究

主要研究了采用复合凝聚法制备苦瓜籽油微胶囊的工艺和技术。以明胶和阿拉伯胶为壁材,研究了不同凝聚pH、芯壁比、壁材浓度、乳化剂对微胶囊形态、产率、效率的影响。最终确定了最佳工艺条件为:凝聚pH为3.9,芯壁比为1∶2,壁材浓度1%,乳化剂采用质量为乳化体系0.1%的Span80。上述工艺条件下,微胶囊形态良好,产率和效率分别为87.7%和90.9%,平均粒径为52.376μm。使用SPME-GC-MS分析了微胶囊化前后芯材挥发性成分的变化,结果表明采用复合凝聚微胶囊化可以掩盖芯材的部分不良风味,改善其可食用性。     

β-谷甾醇微胶囊的复凝聚制备法

以β-谷甾醇为芯材,明胶、阿拉伯胶为壁材,利用复凝聚法制备微胶囊,并用转谷氨酰胺酶(TG酶)进行固化。通过对微胶囊的芯材含量、包埋率和外观形态分析,得出优化的制备工艺条件为:壁材质量分数8%,芯壁比1∶2,复凝聚pH值4.2,TG酶∶明胶=0.2∶1。在此条件下制得的微胶囊外观圆整、大小均一,芯材含量为34.98%,包埋率为48.21%。     

采用复凝聚法和二次包埋工艺制备DHA微胶囊

一种新型DHA微胶囊制备方法,即采用复凝聚法和二次包埋工艺相结合来制备DHA微胶囊。复凝聚法是以明胶和阿拉伯胶为壁材,DHA油脂为芯材,制备DHA微胶囊。二次包埋技术是指将复凝聚法制成的DHA微胶囊湿囊产品选用某种壁材进行再次包埋,在复凝聚法所用壁材的基础上进行加固,改善微胶囊在喷雾干燥过程中囊壁产生的部分裂缝和孔洞,达到提高DHA微胶囊的贮藏稳定性以及延长其货架期的目的。通过研究微胶囊的包埋率和收率,可以得到高品质的微胶囊产品。影响微胶囊包埋率和收率的因素有很多,本文主要研究芯材壁材比例、明胶/阿拉伯胶比率和二次包埋工艺中的壁材组成对DHA微胶囊收率和包埋率的影响。实验结果表明,采用复凝聚法和二次包埋工艺制备DHA微胶囊的优化配方为芯材壁材比1∶2,明胶/阿拉伯胶比率1∶1,二次包埋壁材选用变性淀粉。     

复合凝聚角鲨烯微胶囊的制备研究

为了提高角鲨烯的稳定性,以明胶和阿拉伯胶为壁材、角鲨烯为芯材、转谷氨酰胺酶为固化剂,采用复合凝聚法制备角鲨烯微胶囊。研究了壁材组成、芯壁比、壁材浓度、p H值、搅拌速度、乳化速度等单因素对微胶囊的包埋率、载药量以及粒径大小的影响,并通过正交试验优化了制备工艺。结果表明,角鲨烯微胶囊的最佳制备工艺:明胶:阿拉伯胶(w:w)为1.00:1.00,芯壁比为1:1,壁材浓度为2%,p H为3.6,搅拌速度为500 r/min,乳化速度10 000 r/min。该条件下,角鲨烯微胶囊的包埋率为(68.2±1.5)%,载药量为(40.8±1.2)%,粒径为(98.5±2.5)μm。     

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