铜氨法生产叶绿素铜钠盐工艺优化

叶绿素铜钠盐作为一种安全无毒的水溶性叶绿素衍生物,具有良好的稳定性和着色性,被广泛应用于食品添加剂。本研究对以蚕沙叶绿素为原料制备叶绿素铜钠盐的传统工艺进行了改进,以碱性铜氨置换法半合成叶绿素铜钠盐。选择铜代过程中乙醇质量分数、pH值、反应温度及加铜量4个试验因素,通过正交试验和SAS统计软件进行优化分析,得出最适工艺条件为加铜量为理论值的2.5倍、乙醇质量分数75%、温度55℃、pH11.5。减少置铜过程溶剂乙醇用量10%,得到的产品质量符合国家规定食品添加剂标准。     

几种食品中叶绿素铜钠盐定量方法的研究

<正> 一、前言 叶绿素铜钠盐是用有机溶剂从蚕沙中提取叶绿素,再经皂化、铜代所得到的墨绿色粉状品,是一种天然色素,可在食品加工中作罐头青豆、苦瓜以及糖果、蜜饯、饮料等的着色剂。 我国食品添加剂卫生标准(GB2706—81)中规定叶绿素铜钠盐在食品中最大使用量为0.5克/公斤。有了规定的限量,没有定量的方法作正确的检测也就无法监控。为了确保安全,根据全国食品添加剂标准化技术委员会的提议,我所于1983年进行了青豆、薄荷酒中叶绿素铜钠盐定量方法的研究。     

竹叶制备叶绿素铜钠盐的工艺优化研究

以竹叶为原料,石油醚与95%乙醇复合溶剂为提取溶剂提取叶绿素,叶绿素提取液直接经过皂化、酸化、铜代、净化和成盐等步骤制备叶绿素铜钠盐。对影响产品得率和质量指标的提取、铜代两个关键工艺过程,利用L9(34)正交实验进行工艺条件优化。结果表明,竹叶叶绿素的最佳提取条件为复合溶剂中95%乙醇体积分数为15%、液固比8:1(v:w)、提取温度55℃、提取时间2h;铜代过程最佳条件为乙醇体积分数85%、加铜量为理论值的2倍、反应温度60℃、pH2.5。叶绿素铜钠盐得率0.38%,检验结果主要指标符合食品添加剂国家标准。     

小叶榕叶绿素铜钠盐的制备和理化性质研究

以小叶榕叶为原料,通过化学方法制备叶绿素铜钠盐。采用UV-Vis光谱、FT-IR光谱对叶绿素铜钠盐进行定性分析,表明色素的最大吸收波长为405 nm。并初步研究了光、热、氧化剂、还原剂以及常见食品添加剂对色素稳定性的影响。结果表明,叶绿素铜钠盐的耐热性、耐还原性较好,但耐光性、耐氧化性较差,几种常见食品添加剂对色素稳定性的影响较小。     

食用油中的铜叶绿素

近日，媒体报道某食品企业涉嫌将大豆油掺入铜叶绿素，继而冒充橄榄油销售，报道称长期食用掺有铜叶绿素的油会伤肝肾。那么，铜叶绿素是什么呢？铜叶绿素也叫叶绿素铜，它是叶绿素的一类衍生物，常用的还有叶绿素铜钠盐、叶绿素铜钾盐，在食品工业中常做着色剂使用，也就是我们通常所说的色素。     

莴笋叶绿素锌钠盐的制取及稳定性研究

以莴笋叶为原料,利用萃取得到叶绿素.经皂化、酸化、锌代等过程,制得叶绿素锌钠盐.结果表明,该产品水溶性好,对光、热稳定性较好,具有很好的耐受氧化剂和还原剂的能力.几种常见的食品添加剂对叶绿素锌钠盐的影响不一样.     

甘蓝叶绿素锌钠盐的制备及性质研究

以甘蓝叶为原料,利用萃取得到叶绿素.经皂化、酸化、锌代等过程,制得叶绿素锌钠盐.结果表明,该产品水溶性好,对光、热稳定性较好,具有很好的耐受氧化剂和还原剂的能力.几种常见的食品添加剂对叶绿素锌钠盐的影响不一样.     

关于批准叶绿素铜等2种食品添加剂新品种等的公告

(卫生部公告2013年第2号)根据《中华人民共和国食品安全法》和《食品添加剂新品种管理办法》的规定,经审核,现批准叶绿素铜等2种食品添加剂新品种,N-对苯乙腈基薄荷烷基甲酰胺等2种食品用香料新品种,批准维     

仙人掌叶绿素的提取及叶绿素铜钠盐的制备工艺研究

探讨了"米邦塔"仙人掌叶绿素的提取及制备叶绿素铜钠盐的工艺条件.结果表明,仙人掌叶绿素最佳提取工艺条件为:以80%丙酮及95%乙醇比例为3:1的混合溶液作浸提剂,料液比1:45,浸提温度40℃,浸提时间5h;提取的叶绿素,经过皂化、酸化、铜代、成盐等工序制成叶绿素铜钠盐,产品质量符合国家标准GB3262-82.     

微波技术提取海带叶绿素及其铜钠盐的制备

叶绿素是一种天然的、安全、无毒并具有一定生理功能的脂溶性天然色素,而叶绿素铜钠盐是由叶绿素经化学处理转变而来的.叶绿素铜钠盐具有色泽亮丽、性质稳定、使用安全等特点.本试验以海带为原料,以95%乙醇为浸提溶剂,采用微波技术提取海带中的叶绿素.以海带与浸提溶剂的料液比、微波作用时间、温度、微波功率作为影响因素进行单因素试验,通过分析确定了单因素的最佳实验条件.采用正交实验设计,优化海带叶绿素的提取条件,并将叶绿素提取液浓缩,皂化铜代,与碱反应成盐,干燥,制备叶绿素铜钠.结果表明,温度是影响提取效果的重要因素,其次为微波作用时间,而微波功率为不重要因素,最佳提取工艺参数为:海带与浸提溶剂的料液比为1g ∶ 2OmL,微波作用时间6min,微波功率300w,温度60℃.该方法与传统加热提取方法相比,具有高效、快速、节约能源等优点.由叶绿素提取液制备叶绿素铜钠,得率为4.53%.     

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.     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

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.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of     

The Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.