活性干酵母超氧化物歧化酶提取研究

目的:研究并优化活性干酵母超氧化物歧化酶(SOD)的提取工艺;方法:采用L_9(3~4)正交实验设计,应用邻苯三酚自氧化法测定酶活;结果:提取优化工艺参数为异丙醇浓度90%、搅拌时间18h、第一次丙酮沉淀体积比(丙酮:粗提液)为0.8、第二次丙酮沉淀体积比(丙酮∶粗提液)为0.9,所得酶所得酶活性为840.25U/g,比活力为3361.00U/mg;结论:从活性干酵母提取超氧化物歧化酶(SOD)的最佳提取工艺为异丙醇-丙酮二次沉淀法,大大缩短了生产时间,提高了生产效益,具有极大的应用价值。     

香蕉皮类胡萝卜素提取工艺条件的研究

为探究香蕉皮类胡萝卜素提取及综合利用的可能性,采用单因素试验与正交试验相结合的方法优化香蕉皮类胡萝卜素的提取工艺条件。结果表明:其最佳提取工艺条件为:以丙酮为提取溶剂、料液比1∶25、提取温度45℃、提取时间75min,在此工艺条件下可获得最佳提取效果,类胡萝卜素提取量平均值为12.541 mg/g。另用超声波辅助提取法,得到香蕉皮中类胡萝卜素提取量平均值为13.740mg/g,在提取时间仅为20min的情况下,比普通浸提法的提取量增加了9.56%,提取效率大大提高。     

粗壮脉纹孢菌孢子中β-胡萝卜素的提取优化

研究发现粗壮脉纹孢菌孢子中含有丰富的类胡萝卜素,且β-胡萝卜素占类胡萝卜素含量最高,达到20.08%。试验采用丙酮溶剂从粗壮脉纹孢菌孢子中提取β-胡萝卜素,优化了溶剂浸提温度、浸提时间、料液比3个单因素,并通过响应面法结合HPLC-DAD获得了β-胡萝卜素提取最佳工艺。结果表明,β-胡萝卜素最佳提取条件为:丙酮浸提温度54℃、浸提时间59.2 min、料液比1∶100(g/mL)。在此条件下粗壮脉纹孢菌孢子中β-胡萝卜素提取量最高可达561.082μg/g。按所得最佳工艺进行验证试验,实际粗壮脉纹孢菌孢子中β-胡萝卜素提取量结果为570.168±0.02μg/g,与理论值接近。     

固氮菌β-C1株类胡萝卜素分离提取工艺优化的研究

本文主要报导了破壁方法、浸提溶剂和工艺条件对从固氮菌β-C1菌株中提取类胡萝卜素影响的实验结果.用酸热法对β-C1菌株进行破壁处理最有利类胡萝卜提取,用正交实验法得出的最佳破壁工艺为:盐酸的浓度3mol/L,盐酸的加量30ml/g,破壁时间2min,破壁温度100℃.氯仿、丙酮、甲醇及乙醇等多种溶剂能取得良好的提取效果,但综合考虑,乙醇最理想;用正交实验优化乙醇浸取的最佳条件为:乙醇加量30ml/g菌体,浸提温度为50℃,浸提时间45min,在优化后的条件下进行破壁提取β-C1菌中的类胡萝卜素,提取得率为3.45mg/g(干菌体).     

枸杞中类胡萝卜素超声波法提取工艺优化及其在卷烟中的应用研究

该文研究了超声波辅助提取枸杞类胡萝卜素的工艺,并用SAS 8.0设计优化实验。得出最佳工艺参数:以石油醚:丙酮(2∶1)为提取剂,超声时间32.86 min,超声功率337.54 W,超声温度42.65℃,液料比32.26 g/g,超声提取2次,在次工艺条件下类胡萝卜素提取得率为112.78 mg/100g。实际验证值为110.52 mg/100g,与预测值相比,误差为0.02%,符合实际生产需要。所得产品在卷烟样品中的最佳用量为0.5%;并对卷烟烟气柔和度、质感、口腔甜润感和杂气等方面均有明显改善,有助于提高香气的丰富性、香气质。     

富硒小麦苗中β-胡萝卜素的提取及纯化

对小麦苗中类胡萝卜素超声波辅助提取工艺进行优化,用氧化镁交换层析柱分离和纯化β-胡萝卜素,高效液相色谱法梯度洗脱分离并测定β-胡萝卜素质量浓度和纯化过程含量。结果表明,小麦苗中类胡萝卜素超声波辅助提取最佳工艺参数为料液比1:50(g/mL)、石油醚:丙酮为95:5(V/V)、超声功率300W、提取时间50min、室温条件下提取3次,最优条件下总类胡萝卜素含量12.85mg/g、β-胡萝卜素含量4.86mg/g;提取液在波长447nm处检测到有多处吸收峰,表明富硒小麦苗有色物质组成复杂;氧化镁交换层析柱纯化β-胡萝卜素得率达到93.37%;纯化液在保留时间17.138min处出峰,且保留时间16.726min仍有小峰出现,纯化所得β-胡萝卜素峰可能含有多种结构相似的物质。     

海带中类胡萝卜素提取工艺条件

类胡萝卜素是人体内维生素A的主要来源之一,具有抗氧化、免疫调节、抗癌、延缓衰老等功效。类胡萝卜素来源广泛,普遍存在于动物、高等植物、真菌、藻类。海带中富含类胡萝卜素。为提取海带中的类胡萝卜素,以有机溶剂法优化类胡萝卜素提取条件,通过分光光度计测定类胡萝卜素的提取量,研究不同提取条件对类胡萝卜素提取量的影响。结果表明,提取溶剂采用石油醚-丙酮(1︰1, V/V)、温度50℃、时间50 min、料液比1︰20 (g/m L)、提取2次条件下,类胡萝卜素提取量可达0.427 mg/g,而超声辅助提取和添加抗坏血酸提取,两者均可增加类胡萝卜素提取量,提取量分别可达0.476 mg/g和0.493 mg/g。试验为有机溶剂法提取海带中类胡萝卜素提供技术基础,并为海带中类胡萝卜素功能研究开发提供参考。     

油菜籽中天然类胡萝卜素的提取工艺研究

考察了油菜籽中天然类胡萝卜素的提取工艺.通过单因素实验,研究了提取溶剂种类、料液比、原料粒径、提取温度、提取次数、提取时间等因素对类胡萝卜素提取率的影响.结果表明,提取油菜籽中天然类胡萝卜素的较优工艺条件为:提取溶剂为石油醚-丙酮(1:1,v/v)混合溶剂,料液比(g/mL)为1:30,原料粒径为100目,提取时间为6h,提取温度为40℃,提取次数为3次.     

红酵母番茄红素提取工艺优化

从破壁方法、浸提溶剂及提取条件等方面对黏红酵母番茄红素提取工艺进行优化研究。采用单因素试验对破壁方法及浸提溶剂进行选择,结果表明热酸法是黏红酵母破壁提取番茄红素的最佳方法,丙酮-乙酸乙酯(1:1)混合液是理想的提取溶剂。采用正交试验方法对液料比、提取温度和提取时间等番茄红素提取条件进行优化,得到适宜的提取条件为丙酮-乙酸乙酯(1:1)溶剂添加量60mL/g、提取温度30℃、提取时间3h。在此提取工艺下,得到红酵母番茄红素提取量为4.55mg/g,比未优化时的3.22mg/g增加了41.30%。     

光合细菌类胡萝卜素的提取工艺优化及抗氧化活性研究

为了建立一套相对简单、操作性强、提取率高的光合细菌类胡萝卜素提取工艺,利用单因素和正交试验优化了光合细菌类胡萝卜素的提取工艺。通过超声波辅助提取,分别考察了不同有机溶剂、超声时间、浸提时间、料液比4个因素对光合细菌类胡萝卜素的提取效果,最终获得的最佳提取条件为丙酮石油醚混合液(体积比1∶1)为提取溶剂,超声时间30 min,浸提时间4.5 h,料液比是0.1(g)/6.5(mL)。在该条件下提取,类胡萝卜素的提取量达到9432.56μg/g。通过不同浓度的类胡萝卜素及不同抗氧化剂对猪油POV值的影响试验,证明光合细菌类胡萝卜素具有较强的抗氧化活性,是一种来源于光合细菌、抗氧化效果较好的天然色素类食品添加剂。     

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.     

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.     

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.     

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.