脱氢醋酸钠、丙酸钙及其复配在面包中的防腐作用

研究了脱氢醋酸钠、丙酸钙及其复配形式对面包的防腐效果。结果表明：脱氢醋酸钠和丙酸钙均能有效地延迟面包的霉变时间，且随用量的增大，效果越好；脱氢醋酸纳和丙酸钙复配的最佳比例为2：3。     

食品防腐剂复配形式在面包中的防腐应用研究

GB 2760-2007《食品添加剂使用卫生标准》中规定：面包中允许使用的防腐剂有3种：丙酸盐类、脱氢乙酸及其钠盐、山梨酸及其钾盐。研究了丙酸钙与脱氢醋酸钠两者复配形式、丙酸钙与脱氢醋酸钠和山梨酸钾三者复配形式对面包的防腐效果。结果表明,丙酸钙与脱氢醋酸钠两者复配形式更有利于延长面包保质期,复配的比例6∶4。     

脱氢醋酸钠、丙酸钙及其复配形式在面包中的防腐作用

本文研究了脱氢醋酸钠、丙酸钙及其复配形式对面包的防腐效果。结果表明 :脱氢醋酸钠和丙酸钙均能有效地延迟面包的霉变时间 ,且随用量的增大 ,效果越好 ;脱氢醋酸纳和丙酸钙的最佳比例为 2 :3。     

脱氢醋酸钠、丙酸钙及其复配在面包中的防腐作用

研究了脱氢醋酸钠、丙酸钙及其复配形式对面包的防腐效果。结果表明 :脱氢醋酸钠和丙酸钙均能有效地延迟面包的霉变时间 ,且随用量的增大 ,效果越好 ;脱氢醋酸纳和丙酸钙复配的最佳比例为 2∶3。     

食品防腐剂复配形式在面包中的防腐应用研究

食品防腐剂可防止微生物引起的食品腐败变质,有效延长面包的保质期和销售货架期,而各种防腐剂都有各自的作用范围,两种及以上的防腐剂合理复配使用,往往具有协同作用,比单独使用更为有效。我国《食品添加剂使用卫生标准》GB2760-2007中规定:面包中允许使用的防腐剂有三种:丙酸盐类、脱氢乙酸及其钠盐、山梨酸及其钾盐。本文选用丙酸钙、脱氢醋酸钠和山梨酸钾三种防腐剂,研究了丙酸钙与脱氢醋酸钠两者复配形式、丙酸钙与脱氢醋酸钠和山梨酸钾三者复配形式对面包的防腐效果。防腐剂复配添加量按各自用量占食品添加剂使用卫生标准规定的其最大使用量的比例之和等于1来确定,在面包制作工艺的主面团配料环节加入。结果表明,丙酸钙与脱氢醋酸钠两者复配形式更有利于延长面包保质期,复配的比例6:4。     

脱氢醋酸钠及其复配形式在食品中的防腐应用研究

脱氢醋酸钠是一种广谱性抑菌力极强的食品防腐剂,对霉菌、细菌、酵母的抑制能力尤强.本文系统地研究了脱氢醋酸钠及其复配形式在面制品、肉制品、豆制品中的防腐应用,结果表明单一防腐剂处理,脱氢醋酸钠的抑菌能力优于山梨酸钾、双乙酸钠、丙酸钙;复配形式以脱氢醋酸钠与月桂酸单甘油酯为主体,配以山梨酸钾或丙酸钙、双乙酸钠,其防腐效果较单一防腐剂效果好.     

脱氢醋酸钠及其复配形式在食品中的防腐应用研究

脱氢醋酸钠是一种广谱性抑菌力极强的食品防腐剂,对霉菌、细菌、酵母的抑制能力尤强.本文系统地研究了脱氢醋酸钠及其复配形式在面制品、肉制品、豆制品中的防腐应用,结果表明单一防腐剂处理,脱氢醋酸钠的抑菌能力优于山梨酸钾、双乙酸钠、丙酸钙;复配形式以脱氢醋酸钠与月桂酸单甘油酯为主体,配以山梨酸钾或丙酸钙、双乙酸钠,其防腐效果较单一防腐剂效果好.     

保鲜剂在湿玉米面条应用研究

湿玉米面条是当今广受人们喜爱食品,但由于其水分含量高,导致在常温下容易发霉变质,不能长时间保存。研究和探讨几种防腐保鲜剂：双吸剂、乳酸链球菌素、优利、脱氢醋酸钠、丙酸钙等在常温下对湿玉米面条防腐保鲜效果,结果表明：几种防腐保鲜剂均具有一定防腐保鲜作用,并以Nisin0．1g/kg+优利0．5g/kg+丙酸钙0．315g/kg为最佳；脱氢醋酸钠0．5g/kg+丙酸钙0．4g/kg次之；而双吸剂无论单独使用或结合以上几种防腐保鲜剂同时使用,都具有良好保鲜效果,保鲜期可达2个月。     

槟榔原料优势霉菌分析及防霉剂的研制

分别采用营养琼脂培养基、查氏培养基、牛肉膏蛋白胨培养基、麦氏培养基和高氏Ⅰ号培养基分析原料槟榔中微生物菌群的基本构相,其中霉菌为主要菌群,数量为总菌属的1／3。进一步对槟榔原料干果中的霉菌进行分离纯化,经斜面培养和湿室载片培养后,所得毛霉菌株数为菌株总数的2／5左右,表明毛霉为优势霉菌：分别采用丙酸钙、脱氢醋酸钠及其复合防霉剂对毛霉进行抑菌活性测定,三者的MIC值分别为1．9g／kg,110mg／kg和140mg／kg,抑菌圈直径分别为9．8,8．4,9．3mm,同时确定丙酸钙与脱氢醋酸钠以2：1混合时对毛霉的防霉效果最佳。     

脱氢醋酸钠的防霉作用研究

脱氢醋酸钠是一种新开发的广谱类、抑菌力极强的食品防腐剂，对霉菌、酵母菌、细菌的抑制能力特别强，广泛地应用于各类食品加工行业中。本文研究了脱氢醋酸钠在酱油、酱菜、面包、蛋糕、广式月饼、人造奶油、腐乳、米面制品、各式月饼、汤料、饮料中的应用。结果表明脱氢醋酸钠不仅能应用于酱油、酱菜、果汁、面包、蛋糕、广式月饼、人造奶油和腐乳的防腐、防霉，而且能用于米面制品、各式月饼、汤料和饲料的防腐、防霉，防腐、防霉作用持久，值得推广应用。     

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