产乳酸芽孢杆菌发酵液对山药护色及多糖免疫活性的影响

结合单因素试验和响应面法优化产乳酸芽孢杆菌发酵时间、发酵液添加量、护色时间对山药多糖得率和山药相对褐变度的影响,并对比该护色液和亚硫酸钠护色液对于山药中酶促褐变和山药多糖免疫活性的影响。结果表明,最佳护色工艺为采用添加10%发酵时间为34 h的产乳酸芽孢杆菌发酵液配制的护色液、护色时间为1 h,在此条件下,多糖得率为12.44%,相对褐变度为43.05%。该护色工艺能够有效抑制山药中多酚氧化酶(polyphenol oxidase,PPO)和过氧化物酶(peroxidase,POD)活性。该工艺护色后的山药多糖刺激小鼠巨噬细胞RAW264.7分泌肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素1(interleukin-1、IL-1β)的水平显著高于传统亚硫酸钠护色后的山药多糖。说明,采用该工艺护色后山药多糖的免疫活性显著优于采用亚硫酸钠护色后的山药多糖。     

山药饮料的护色和稳定性工艺研究

对山药饮料加工过程中易引起褐变的环节及稳定性进行了研究,比较了不同护色剂的护色效果和不同稳定剂的稳定效果,并确定了最佳护色工艺及稳定剂。结果表明:最佳护色条件为山药在20℃的质量分数0.5%抗坏血酸+0.5%柠檬酸+0.01%氯化钠水溶液中浸泡15 min,可防止其切片后褐变;另外,复配稳定剂(质量分数0.2%CMC+0.15%瓜尔豆胶+0.15%卡拉胶)对山药果肉饮料的稳定效果最为明显,所得山药饮料的浆液组织形态均匀,长时间放置不分层。     

山药中多酚氧化酶的活性测定及其护色研究

研究了山药中多酚氧化酶(PPO)的最适pH值、最适温度,设计了不同护色方案,以确立山药的最佳护色条件。采用分光光度法研究pH值、温度对酶活性的影响;比较不同护色液对酶活力的影响;将山药经不同护色条件护色后,低温烘干,粉碎过筛得山药粉,用分光光度法测定其甲醇-水溶液(1∶1)的吸光度。结果表明,以邻苯二酚为底物,山药PPO的最适pH值为5.6,最适温度为35℃,山药的最佳护色条件为:以0.25%的Na2SO3为抗氧化剂,并配以0.25%的柠檬酸和1.5%的NaCl为护色液。     

均匀设计法优化鲜切山药的护色工艺

鲜切山药在空气中容易被氧化产生褐色素,影响其品质。通过单因素实验,研究了常用护色剂EDTA-2Na、抗坏血酸、氯化钠及柠檬酸对鲜切山药的护色效果,并确定了其单独使用时的较佳浓度。通过均匀设计安排实验,对鲜切山药的护色工艺进行优化,得到优化护色配方:0.8%EDTA-2Na,2.0%柠檬酸,0.2%抗坏血酸。通过对照实验,研究了不同前处理0.005%,0.010%Na Cl O消毒及65℃烫漂对鲜切山药的护色效果,结果表明:0.005%,0.010%Na Cl O消毒及65℃烫漂对鲜切山药均具有良好的护色效果,其中0.005%Na Cl O效果优于0.010%Na Cl O。     

紫山药紫甘薯保健酸乳的开发研究

以紫山药、紫甘薯和牛乳为原料,研发出一种集营养与保健作用为一体的新型保健饮料——紫山药紫甘薯保健酸乳;对其生产过程中的护色、发酵原料配比和发酵工艺参数分别进行了正交试验筛选。结果表明:紫山药紫甘薯最佳护色条件为柠檬酸0.4%、维生素C 1.3%、氯化钙0.30%,护色时间2 h;发酵原料最佳配比V(为紫山药原浆)︰V(紫甘薯原浆)=2︰1、原料乳的添加量为25%、糖的添加量为4%;最佳发酵工艺参数为发酵时间7 h、发酵温度43℃、接种量4%。     

山药清水罐头的加工工艺

根据食品罐藏的基本原理，探讨了山药清水罐头的加工工艺，并且针对山药在加工过程中容易变色的问题进行了护色试验，筛选出了护色效果好、食用安全的护色方法，研制出了能够保持山药天然色泽和风味的罐头产品。     

山药罐头加工中护色条件的研究

目的研究山药罐头加工中最佳的护色条件。方法用柠檬酸、维生素C及氯化钙为护色剂进行护色实验。结果最佳护色条件为:0.5%柠檬酸 1.0%维生素C 0.25%氯化钙。结论3种护色剂配合处理后可防止山药褐变,提高山药罐头质量。     

微波对鲜切山药护色及品质的保持

分别使用不同微波功率100、300、500 W对鲜切怀山药进行80 s处理,并在(4±1)℃下保存,贮藏期间每3 d测定鲜切山药的亮度、褐变度、多酚氧化酶活性、过氧化物酶活性、电导率、水分含量、失重率和感官评价指标。结果表明,微波处理能够有效抑制鲜切山药的相关褐变酶多酚氧化酶(polyphenol oxidase,PPO)与过氧化物酶(peroxidase,POD)的活性,延缓整体褐变,维持山药乳白色泽,同时能维持细胞膜的完整性,但微波功率对护色效果有较大影响,功率不足会导致护色效果不显著,功率过高则会引起鲜切山药失水失重加剧,实验中以微波功率300 W、处理时间80 s的保鲜效果最佳,能很好地维持鲜切山药的色泽,且贮藏保鲜期可达到15 d。该研究为今后鲜切果蔬保鲜的研究提供了微波护色方向。     

抑制山药中多酚氧化酶活性的研究

采用分光光度法研究了pH值、温度以及护色液对山药中多酚氧化酶(PPO)活性的影响。结果表明,抑制山药PPO活性的pH值应控制在2.4或7.2,温度应控制在5℃左右;质量分数0.03%EDTA、0.4%抗坏血酸、0.5%柠檬酸配比的混合护色液可以有效抑制山药中多酚氧化酶(PPO)的活性。     

山药罐头加工中护色条件的研究

目的 研究山药罐头加工中最佳的护色条件。方法用柠檬酸、维生素C及氯化钙为护色剂进行护色实验。结果最佳护色条件为：0．5％柠檬酸＋1．0％维生素C＋0．25％氯化钙。结论3种护色剂配合处理后可防止山药褐变，提高山药罐头质量。     

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

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