热带假丝酵母发酵法生产木糖醇的研究

目的利用热带假丝酵母研究发酵木糖生产木糖醇的发酵条件。方法采用摇瓶发酵对发酵生产条件,如培养基中初始木糖浓度、接种量和通气量、氮源、pH等进行优化,通过测定发酵液中木糖的残留量、木糖醇的转化率来确定适合的发酵工艺。结果通过实验得到最佳培养基条件为:初始木糖50g/L,蛋白胨5g/L,酵母粉10g/L,硫酸镁0.5g/L、磷酸二氢钾5g/L,硫酸铵1g/L;最佳发酵条件为:pH 6.0,摇瓶发酵装液量50mL/250mL,转速200 r/min,发酵温度30℃,发酵时间28h。结论优化了木糖醇的发酵工艺。     

固定化热带假丝酵母发酵氨浸稻秸水解液生产木糖醇

采用海藻酸钙固定化热带假丝酵母细胞发酵氨水浸泡稻秸半纤维素水解液生产木糖醇。为了提高木糖醇的转化率,对发酵条件进行了研究。发酵在250 mL锥形瓶中进行。向水解液中补充适量氮源和营养盐等营养物质提高了木糖醇的生产速率,但木糖醇转化率没有因此而提高。适宜的初始pH和细胞干浓度分别为4-5和1.22 g/L。在这些条件下,进行了固定化细胞重复法较高浓缩度水解液的试验。结果发现,固定化细胞能在初始木糖浓度为104.2 g/L的水解液中重复批式发酵5次,木糖醇平均得率和生产速率分别为0.737 g/g和0.533 g/(L.h)。     

酒糟酸水解液发酵生产木糖醇的研究

采用热带假丝酵母(Candida tropicalis 1779)发酵酒糟酸水解液生产木糖醇,分别利用单因素实验和正交实验考察了影响发酵效果的工艺条件。发酵在250mL摇瓶发酵瓶中进行。结果表明,当种子龄27h、接种量20mL和氮源添加量20mL时发酵效果最好。该条件下发酵液中木糖醇浓度为11.85mg/mL,木糖利用率为45.62%。发酵实验表明酒糟酸水解液作为碳源发酵生产木糖醇具有可行性。     

响应面法优化酒糟水解液发酵生产木糖醇

研究热带假丝酵母(Candida tropicalis)GIM2.7发酵酒糟水解液生产木糖醇的最佳工艺条件,提高酒糟资源的利用率。在单因素试验结果的基础上,选择主要因素接种量、装液量、有机氮源添加量进行响应面优化。结果表明,当接种量为16%、有机氮源添加量5%、装液量109 mL/250 mL时,木糖醇转化率可达到57.8%,与预测值(60.4%)相接近,说明响应面优化酒糟水解液生产木糖醇的发酵条件是有效的。     

L-鸟氨酸发酵废菌渣水解固形物回用工艺的研究

以L-鸟氨酸发酵废菌渣水解固形物为有机氮源,进行L-鸟氨酸发酵工艺条件的研究,实验结果发现最佳回用工艺条件为:水解时间20 h,水解温度90.0℃,水解液加入量6.5 g/100 m L,6.0 mol/L硫酸溶液(m L)与含水废菌渣固形物(g)之比1∶2.5。在上述条件下,L-鸟氨酸产量达到了37.47 g/L,与酵母膏为有机氮源进行的鸟氨酸发酵差异不明显,且产量稳定。     

木薯粉酒精浓醪发酵条件的优化

以木薯粉为原料进行浓醪酒精发酵,在前期优化液化糖化条件的基础上,分析了培养基成分以及温度,pH值等条件对发酵的影响。实验结果表明,在优化的液化糖化条件下进行木薯粉浓醪酒精发酵,氮源和无机盐的最适添加量为尿素0.25%(w/w),MgSO4·7H2O0.45g/L,KH2PO41.50g/L,CaCl20.20g/L,发酵最适温度为33℃,最适初始pH4.5,酵母接种量10%(v/v),发酵时间48h。在此条件下发酵成熟醪酒精浓度高达17.2%(v/v),淀粉利用率达91%。     

不同氮源种类对米根霉RM167-12发酵生产L-乳酸的影响

蔗糖糖浆水解液经模拟移动床(SMB)分离后可得到果糖液和葡萄糖液。通过以该葡萄糖液作为碳源,以不同氮源种类:硝酸铵、硫酸铵、尿素、蛋白胨和麸皮汁作比较,考察不同氮源种类对米根霉RM167-12摇瓶发酵生产L-乳酸的影响程度,确定3%(w/v)麸皮汁作为RM167-12最佳摇瓶发酵氮源,产酸量达到118.52g/L。用3%麸皮为发酵罐发酵产酸的氮源,经3次液体深层通风搅拌发酵验证,在5L发酵罐发酵L-乳酸积累量最高可达116.31g/L。     

热带假丝酵母发酵甘蔗渣水解液生产木糖醇

用超声辅助双碱(NaOH/氨水)的方法预处理酶解蔗渣,利用热带假丝酵母发酵蔗渣水解液生产木糖醇,优化发酵的工艺参数。以木糖醇质量浓度为参照指标,分别考察了种龄、接种量、木糖初始质量浓度对热带假丝发酵蔗渣水解液生产木糖醇的影响,得出种龄为26 h,接种量为10%,木糖初始质量浓度为100 g/L为发酵木糖醇最适条件。在最适条件下,热带假丝酵母菌以蔗渣酶解液为原料发酵54 h,最终木糖醇质量浓度达到62.98 g/L。结果证明,热带假丝酵母菌可以有效发酵蔗渣水解液,有一定的研究意义。     

木薯粉酒精浓醪发酵条件的优化

以木薯粉为原料进行浓醪酒精发酵,在前期优化液化糖化条件的基础上,分析了培养基成分以及温度,pH值等条件对发酵的影响.实验结果表明,在优化的液化糖化条件下进行木薯粉浓醪酒精发酵,氮源和无机盐的最适添加量为尿素0.25%(w/w),MgSO4·7H2O 0.45g/L,KH2PO4 1.50g/L,CaCl2 0.20g/L,发酵最适温度为33℃,最适初始pH4.5,酵母接种量100,6(v/v),发酵时间48h.在此条件下发酵成熟醪酒精浓度高达17.2%(v/v),淀粉利用率达91%.     

玉米秸秆水解液发酵产生物油脂试验研究

对发酵性丝孢酵母IFFI01368发酵玉米秸秆水解液产脂的培养基组成和发酵条件进行了探索,并对油脂的脂肪酸组成进行了鉴定.结果表明最佳条件为:补加4%的蔗糖,酵母膏、硫酸铵为氮源,碳氮比100:1,pH 5.5,发酵摇瓶装液量为300 mL三角瓶装玉卷秸秆水解液50 mL,时间4d.在最佳条件下于27℃、150 r/min振荡发酵培养,所得生物量为23.5 g/L,油脂含量42.7%,产脂能力为10.03 g/L.所产生物油脂的脂肪酸主要为棕榈酸、油酸和硬脂酸.     

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.     

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.     

National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the "13~(th) Five-Year Plan"

In Apri Commi major p Plan＂ （h 2014, the National Development and Reform ssion issued an announcement for selection of reliminary research projects for the ＂13th Five-Year ereafter referred to as ＂The Announcement＂）     

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 scientific     

Contamination of animal feed and food from animal origin with mineral oil hydrocarbons

Oils and fats used for the production of animal feed can become contaminated with mineral oil material originating from gas oils (C₁₈-C₃₅) or synthetic oils (poly alpha olefins, C₂₅ to beyond C₄₅). An important cause is assumed to be the discharge of waste oils, such as motor oil and hydraulic oils. Mineral oil material was analysed by on-line LC-GC-FID directly in the fat or in a raw extract from animal feed or foodstuffs. In Switzerland in summer/autumn 1999 concentrations in oils and fats for feed production were often found to be between 100 and 1000mg/kg. In the feeds, the average concentration was around 100mg/kg with values ranging up to a maximum of 1000mg/kg; few samples were free of contamination. In animal body fat, the average concentration determined in summer 1999 was 25mg/kg, with a maximum of 150mg/kg, although in samples from December 1999, contamination was substantially lower. In the fat phase of eggs, the average concentration was 30mg/kg, with a maximum of 80mg/kg. Paraffin oil is used for feed production, which may account for part of the contamination problem (e.g. eggs).