带壳百香果与甘蔗汁混酿复合果酒工艺研究

将带壳百香果和甘蔗汁作为原料酿造复合果酒,并研究其发酵工艺。 运用单因素试验和正交试验对发酵破壳时间、原料配比、原料初始含糖量、主发酵温度及主发酵时间进行优化。 结果表明,百香果甘蔗复合果酒的最优工艺条件为：百香果发酵破壳时 间5d,百香果与甘蔗汁配比1∶3（g∶mL）,调节原料初始含糖量至32.5%,于发酵温度24℃条件下发酵9d。 在此最佳工艺条件下,百香果甘蔗复合果酒感官评分达到79分,酒精度达到14.1%vol,色泽呈玫瑰红色,澄清透亮,具有典型的百香果浓郁香气和甘蔗汁的清 香风味。     

响应面法优化百香果果醋澄清的酶解工艺

从蛋白酶、淀粉酶、果胶酶、糖化酶4种酶中筛选出2种酶进行复合，对百香果果醋进行澄清处理，以百香果果醋透光率为参考指标，通过响应面法优化百香果果醋澄清的酶解工艺。结果表明，百香果果醋澄清的酶解工艺响应面模型的建立具有稳定性，最适澄清酶解工艺条件为复合酶配比(淀粉酶∶果胶酶)3∶2、复合酶添加量145 mg/kg、澄清温度46.5℃、澄清时间125 min。在此优化工艺参数下，百香果果醋透光率可达85.7%,与原醋相比提高了27%,澄清后的百香果果醋外观呈浅黄色，色泽透亮清澈，无肉眼可见杂质。     

响应面优化柚子百香果果酒发酵工艺及其抗氧化性

目的以柚子和百香果为原料,研究复合果酒发酵的最佳工艺。方法通过单因素实验分别考察果汁比例、含糖量、接种量、发酵时间、pH、发酵温度等因素对酒精度和感官评分的影响。以酒精度和感官评分为指标,采用响应面法建立数学模型,筛选最佳发酵工艺条件。结果柚子百香果复合果酒发酵最佳工艺条件为:柚子百香果果汁比例为3:1(V:V),含糖量18%,发酵温度26℃,接种量0.04%, pH 4.0,发酵时间7 d,此条件下柚子百香果复合果酒感官评分为79.86,模型方程理论预测值为81.28,两者相对误差为1.74%,酒精含量为10.14%。柚子百香果复合果酒具有一定的抗氧化活性,对ABTS自由基的清除率为62.38%,对羟基自由基清除率46.56%,超氧阴离子清除率40.44%, DPPH自由基抑制率75.62%。结论所得成品果酒色泽呈淡红色,有典型的柚子和百香果风味,酒香清醇,口感清爽,酸甜适中,澄清透亮。     

亚临界法提取百香果籽油工艺优化及其组分分析

本文采用亚临界法提取百香果籽油,基于单因素试验(提取温度、提取次数和提取时间等),通过正交试验及统计方法优化亚临界法提取百香果籽油工艺参数及获得影响提取率因素的主次顺序,结合百香果籽粉末SEM表征及最优提取工艺条件下的重复实验结果,验证优化结果的可靠性。通过对百香果籽油的FT-IR和GC表征,确定百香果籽油主要组分及含量;通过TG/DSC表征,探讨百香果籽油的热稳定性。结果表明：亚临界法提取百香果籽油最佳工艺条件：提取温度50 °C、提取3次、50 min/次,该工艺条件下百香果籽油提取率(23.776±0.178 %)高于超声和索氏提取。亚临界提取中的温度和次数、温度和时间及次数和时间二因素作用对百香果籽油提取率可见显著正协同效应;温度、次数和时间三因素的正协同效应促进百香果籽油提取率显著增加。亚临界法提取所得油的组分更丰富(11种),不饱和脂肪酸含量(88.88%)更高。百香果籽油在氮气气氛下热稳定好,超过347 °C开始热分解。     

ZTC1+1-Ⅱ澄清剂用于昆参片水提液的纯化研究

目的:研究纯化昆参片水提液的工艺.方法:以纯化前后昆参片水提液中总多糖含量和浸膏率为考察指标,比较乙醇沉淀法、壳聚糖澄清剂和ZTC1+1-Ⅱ澄清剂对提取液的纯化效果,并用单因素考察法确定ZTC1+1-Ⅱ澄清剂的最佳纯化工艺.结果:ZTC1+1-Ⅱ澄清剂优于乙醇沉淀法和壳聚糖澄清剂,最佳纯化工艺为澄清剂用量5%B+2.5%A,药液浓度0.2g/mL,搅拌速度100r/min.结论:ZTC1+1-Ⅱ澄清剂可用于纯化昆参片水提液.     

甘薯饮料澄清工艺的研究

本文研究了甘薯饮料的最佳澄清工艺.本试验通过加入淀粉酶、果胶酶、壳聚糖作为澄清剂以除去引起混浊的成分淀粉、果胶、纤维素、酚类、可溶性蛋白等,以透光率为衡量指标,考虑温度、pH值、时间的因素影响进行单因素和正交试验,进而得到最佳澄清条件.     

果胶酶和壳聚糖对无核黄皮发酵酒澄清效果的比较研究

研究了果胶酶和壳聚糖对无核黄皮发酵酒的澄清效果,并通过正交试验及综合评比分析,确定了最佳澄清剂和工艺条件,即壳聚糖法:壳聚糖用量1.0 g/L,pH值为3.0,温度30℃,澄清时间24h.澄清后的发酵酒澄清透明,稳定性增加.     

鲜灵武长枣酒澄清工艺的研究

以宁夏灵武长枣为原料,对鲜灵武长枣鲜枣汁发酵酒发酵工艺和澄清工艺进行了研究。采用正交试验,优化发酵工艺过程中的关镑陛因素,得出生产红枣酒的最佳发酵工艺条件;对澄清剂进行了单因素及复配实验,选择出最佳的澄清方法。鲜枣汁经发酵、澄清后得到最终获得了一种色、香、味、外观俱佳的高品质鲜枣汁发酵酒。     

响应面法优化百香果的酶解工艺

以百香果为原料,响应面法优化果胶酶、纤维素酶酶解百香果全果的最佳酶解工艺。单因素实验研究料液比、p H、酶解时间、酶解温度、酶添加量对百香果出汁率的影响,利用Box-Behnken设计实验响应面法优化三个因素对酶解全果百香果果汁工艺。响应面法优化结果表明,百香果酶解最佳工艺参数为温度38.8℃,果胶酶添加量0.06‰,纤维素酶添加量0.09‰,在此条件下酶解百香果全果果汁60 min,出汁率为94.21%,和理论值94.237%模拟较好。本研究建立百香果酶解工艺二次线性回归模型准确有效,优化百香果酶解工艺参数是可行的,有一定的实用价值,可为百香果果汁、果酒及果醋等进一步研究提供理论依据。     

复合澄清剂处理柚子发酵酒的澄清效果研究

针对柚子果酒难以澄清的情况,采用硅藻土、壳聚糖、木瓜蛋白酶、明胶、交联聚乙烯吡咯烷酮（PVPP）、皂土6种澄清剂进行单因素试验,考察其对柚子果酒的澄清效果。以透光率和感官品评为评价指标,选取澄清效果较好的澄清剂进行复合,并优化澄清工艺。单因素试验结果表明,皂土和壳聚糖为最佳澄清剂,正交试验结果表明,柚子果酒的最佳澄清工艺为：皂土-壳聚糖澄清剂质量比为0.75∶1.00、处理温度35 ℃、处理时间11 h。在此优化条件下,柚子果酒透光率达91.7%,比原果酒的透光率提高了35.5%。     

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.     

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.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

Focus on China's Paper Industry

In the English section of this issue, 〈China Paper Newsletters〉 will introduce ＂National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the ＇13th Five-Year Plan＇＂, ＂2013 Annual Report of China＇s Paper Industry＂, and news of projects and other policies.     

Listen to downstream & search for innovation

正Nowadays,textile enterprises are all taking efforts in transformation and upgrading,like improving producing capacity and optimizing production structure to face market downturn.It claimed a higher request to the standard of textile equipments.In the upcoming of ITMA ASIA+CITME 2014exhibition,this magazine have interviewed several branch associations and a series of relative enterprises,to summarize industrial developing status