蔗髓制备木糖、L-阿拉伯糖的工艺优化

研究了蔗髓稀酸水解条件对木糖、L-阿拉伯糖得率的影响。在单因素实验的基础上,用正交实验法对水解条件进行优化。实验结果表明:在液固比15:1、硫酸浓度2.0%、温度120℃、时间60 min水解条件下,木糖得率最大为25.93%,L-阿拉伯糖得率最大为4.22%。     

玉米芯制备木糖的工艺研究

目的研究玉米芯制备木糖的最佳工艺条件。方法以颗粒状玉米芯为原料,采用酸解法制备木糖,选择不同的酸度、酸解温度、酸解时间和固液比,以木糖提取率确定最佳工艺条件。结果最佳工艺条件为:酸解温度120℃,酸度1%,玉米芯和工艺水的固液比1:10,酸解时间2 h。水解液经活性炭脱色和离子交换后透光率大幅度提高,在420 nm下透光率可达90%以上;电导率大幅度降低,说明去除了糖液的各种离子。结晶后木糖产率较高,8 t玉米芯可产1 t成品木糖。结论采用此工艺条件制备木糖,木糖的产率较高。     

响应面法优化玉米芯中木聚糖的提取工艺

为提高玉米芯中木聚糖的得率,采用响应面法优化碱法提取玉米芯中木聚糖的工艺条件,对碱液质量浓度、固液比、处理时间、处理温度4个因素进行单因素试验。根据单因素试验结果设计中心组合试验,以木聚糖得率为指标值,采用响应面分析法确定最优工艺参数。结果表明：NaOH溶液的质量浓度为25g/100mL、固液比1:25(g/mL)、94℃抽提3h,在上述条件下木聚糖得率为24.39%,比单因素试验的最高得率20.35%高出19.85%,与模型的预期值24.41%基本相符。响应面优化法能够提高玉米芯的木聚糖得率。     

白酒丢糟酸水解制备木糖及其结构变化

采用混合酸水解法提取白酒丢糟中的木糖,并研究木糖提取过程中丢糟的结构变化。以木糖收率为指标,考查酸解温度、固液比、混合酸浓度和酸解时间4个因素对木糖提取效果的影响,利用正交试验优化工艺参数。结果表明,从丢糟中提取木糖的最优条件为温度110℃、固液比1∶12(g∶mL)、混合酸浓度1.5%和时间145min,该条件下的木糖收率为61.24%。经酸水解法提取木糖后,丢糟的木质纤维结构变化明显,孔隙率和比表面积增加,形貌结构改变,半纤维素和纤维素无定形区被降解,导致结晶度增加。     

超声波提取接骨草花中乌索酸的工艺研究

利用超声波辅助提取法提取接骨草花中乌索酸。通过考察乙醇浓度、固液比、超声波时间对提取乌索酸得率的影响,设计正交实验,得出最佳提取工艺。结果表明各因素对提取乌索酸的影响依次为乙醇浓度>固液比>超声时间。最佳提取工艺是乙醇浓度为80%,固液比为1∶60g/mL,提取时间为45min。在此条件下,乌索酸在盛花期中得率为0.83%,在花蕾期中得率为0.81%。     

微波辅助稀酸降解玉米芯的工艺优化及其效果研究

为提高木质纤维素的利用率及经济效益,以稀酸为催化剂,采用微波辐射相结合的方法对玉米芯进行水解研究。以还原糖得率和原料转化率为指标,通过单因素试验和正交试验考察微波辐射时间、微波功率、酸浓度、固液比和秸秆颗粒大小等对玉米芯水解的影响,利用扫描电镜(SEM)和红外光谱(FT-IR)分析原料及不同方法处理后的水解残渣。结果表明,微波辐射稀酸催化玉米芯水解的最佳工艺条件为:玉米芯粉碎至60~80目,常压,固液比1:8(g/mL),酸浓度13%,微波功率130 W,反应时间20min,该条件下还原糖得率为66.41%、原料转化率为52.70%。SEM及FT-IR分析表明微波辅助稀酸的降解效果较好,反应后玉米芯的表面结构遭到了严重的破坏,其半纤维素基本被水解,同时也有部分纤维素被水解。     

豌豆皮酸水解糖化工艺研究

研究豌豆皮硫酸水解条件对木糖、阿拉伯糖收率的影响。在单因素实验的基础上,用正交实验法对水解条件进行优化。实验结果表明:在固液比1∶12、硫酸浓度1.5%、水解温度110℃、水解时间120min水解条件下,对10kg豌豆皮进行预处理后水解,水解液木糖收率10.69%,阿拉伯糖收率21.58%;进一步对水解液进行脱色、除盐、浓缩、分离、结晶,最后得到木糖晶体521.5g,阿拉伯糖晶体978.5g。     

酸催化水解处理甘蔗叶提取木糖的研究

为了从蒸汽爆破预处理后得到的甘蔗叶中提取木糖,采用酸催化水解法处理甘蔗叶研究了提取木糖过程中各因素对木糖溶出量的影响。结果表明,木糖得率随硫酸浓度先增大后减小,随液料比增大而增大,随反应时间延长先增大后减小,随水解温度增高,先增大后减小。最佳酸解工艺条件是,硫酸浓度2%,反应时间2 h,反应温度100℃,液料比是11:1(v/w)。     

蜂胶黄酮类化合物超临界萃取工艺研究

通过单因素实验和正交实验研究,超临界流体萃取蜂胶黄酮类化合物的工艺进行了优化设计。试验结果表明:影响萃取得率的各因素强烈程度顺序是:萃取压力>乙醇浓度>固液比>萃取温度;最佳萃取实验工艺条件为:萃取压力:25MPa,乙醇浓度95%,固液比:6:1,萃取温度为500C,萃取时间为4h,流体流速为35kg/h。而且黄酮类化合物得率较高、萃取物纯净、色泽金黄、纯度高。     

热辅助酸水解麦糟提取低聚木糖的工艺研究

单因素法考察酸浓度、提取时间、温度和料液比对低聚木糖提取率的影响,并在此基础上用正交设计对低聚木糖的提取工艺进行优化,得出优化的工艺为:磷酸浓度0.8mol/L,提取时间60min,温度160 ℃,料液比1:10.在此工艺条件下低聚木糖的提取率为48.97%,平均聚合度为2.89.     

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.     

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.