卡拉胶、黄原胶、海藻酸钠、瓜尔豆胶及转谷氨酰胺酶对鸡肉肠出品率和硬度的影响

本实验采用两因素析因试验设计,研究了转谷氨酰胺酶和四种亲水胶体(卡拉胶、黄原胶、海藻酸钠、瓜尔豆胶)对鸡肉肠硬度和出品率的影响。结果表明,随着浓度的增加,四种亲水胶体均可显著增加鸡肉肠的出品率(p<0.01);转谷氨酰胺酶对鸡肉肠的出品率没有显著的影响,且与各亲水胶体之间均无显著交互作用(p>0.05)。转谷氨酰胺酶可显著增加鸡肉肠的硬度(p<0.05),卡拉胶对转谷氨酰胺酶处理的鸡肉肠硬度无显著影响,而黄原胶、海藻酸钠、瓜尔豆胶则均极显著降低了鸡肉肠的硬度(p<0.01)。     

复配型抗馒头老化改良剂的实验研究

通过对复配型添加剂在馒头生产中的应用研究和对比实验,开发出在馒头中增添复配型添加剂的生产工艺,可以有效地解决馒头变硬、口感不佳、失水等问题。采用单因素试验和正交试验研究了两种亲水胶体（黄原胶、海藻酸钠）和高温α-淀粉酶对在4℃下储存的馒头的抗老化效果。试验结果表明,黄原胶、海藻酸钠、高温α-淀粉酶对馒头均有一定的抗老化效果。抗馒头老化效果较好的复配比例：以面粉为基准,黄原胶添加量为0.15%、海藻酸钠添加量为0.10%、高温α-淀粉酶添加量为0.0001%。     

亲水胶体对红芽芋全粉理化特性和消化特性的影响

分别将κ-卡拉胶、黄原胶和瓜尔胶3种亲水胶体以不同比例(0.4%、0.8%)与红芽芋全粉进行复配,研究两者复配后理化特性和消化特性的变化。结果表明,添加3种胶体后,复配体系的持水性、膨胀度和RVA值均有不同程度的提升,其持油性和回生值有所下降。κ-卡拉胶和瓜尔胶可降低体系析水率,提高冻融稳定性,而黄原胶只有在第3次冻融处理下能提高冻融稳定性。与空白组相比,3种胶体复配体系的硬度和咀嚼性下降,黏度上升。在消化特性结果中,添加3种胶体均可使易消化淀粉(RDS)含量降低,抗性淀粉(RS)含量升高,其中加入0.8%黄原胶能使RS质量分数从10.11%升至19.85%。     

基于亲水胶体改性和混料设计优化传统粘豆包的配方

目的 用亲水胶体改性和混料设计来优化传统粘豆包的配方, 改善其食用品质。方法 选用3种食品工业中常用的亲水胶体, 卡拉胶、黄原胶和瓜尔豆胶, 对糯玉米与糯大黄米淀粉进行改性, 通过快速粘度分析仪和质构仪比较回生值和硬度的变化, 筛选出复配糯玉米粉和复配大黄米粉作为粘豆包的制作原料, 然后利用混料设计优化粘豆包配方。结果 卡拉胶、黄原胶、瓜尔豆胶对糯性谷物淀粉有着良好的抗老化作用, 回生值都明显变小, 尤其瓜尔豆胶效果最明显; 通过混料设计发现当糯大黄米为33%, 糯玉米粉为24%, 红豆馅为43%时感官评分最高。结论 利用混料设计优化传统粘豆包的生产配方, 感官评分高, 传统粘豆包品质得到改善。     

复配胶体对面包烘焙品质的影响

研究了不同胶体复配(黄原胶、瓜尔豆胶、羟丙基甲基纤维素(HPMC)和海藻酸钠)对面包烘焙品质的影响.结果表明:面包中添加复配胶体可弥补添加单一胶体时在比容、质构特性和感官等方面的不足,改善面包的烘焙品质,提高面包抗老化性能,延长产品货架期.黄原胶、海藻酸钠与HPMC最优质量配比为1:2:6,质量分数为0.15％时,面包的烘焙品质和抗老化效果得到了明显的改善.     

响应面法优化油塔子复合抗老化剂配方

本研究采用响应面法探讨一种油塔子复合抗老化剂配方。以乳化剂(单甘酯、硬脂酰乳酸钙(calcium stearyl lactylate,CSL)、硬脂酰乳酸钠(sodium stearyl lactate,SSL)、大豆卵磷脂)、酶制剂(α-淀粉酶、麦芽糖淀粉酶、木聚糖酶、脂肪酶)、亲水性胶体(黄原胶、羧甲基纤维素钠(sodium carboxymethyl cellulose,CMC)、结冷胶、海藻酸钠)为抗老化剂,在单因素试验的基础上,通过响应面法,以硬度偏差率的绝对值为响应值,考察12种抗老化剂对油塔子硬度和感官的影响,优化复合抗老化剂配方。结果表明:大豆卵磷脂添加量0.357%,木聚糖酶添加量0.00366%,黄原胶添加量0.439%,在此配方下,硬度偏差率的理论值为5.69%,而实测值为6.68%,理论值和实测值基本相符,说明此配方的协同抗老化效果最佳。     

复配亲水胶体对牛肉丸品质特性的影响

比较卡拉胶、刺槐豆胶、瓜尔胶组成的复配亲水胶体两种添加方式(干粉添加、凝胶添加)对牛肉丸品质特性的改良效果,得到亲水胶体以干粉形式添加对牛肉丸的硬度、持水性、凝胶强度增强效果更明显,两者添加方式之间差异显著(P0.05),采用混料设计的方法得到3种亲水胶体的最佳配比为卡拉胶59%,刺槐豆胶22%,瓜尔胶19%,最佳添加量为0.8%,在该条件下,牛肉丸的硬度为2267g、持水性为82.1%、凝胶强度为1561g·mm。     

花生乳干法生产工艺增稠剂稳定性研究

经过对果胶、卡拉胶、黄原胶、海藻酸钠、羧甲基纤维素钠(CMC)、藻酸丙二醇酯(PGA)等11种稳定剂初步筛选,确定了黄原胶、卡拉胶、海藻酸钠是稳定效果最好的多糖类物质。单因素试验时,黄原胶的稳定效果最好,且添加量0.02%为最佳用量。添加黄原胶、卡拉胶、海藻酸钠后都出现不同的油脂析出和沉淀,3种稳定剂对花生乳的稳定性没有规律可循,说明单一的稳定剂满足不了对花生乳溶液稳定性的需要,对稳定剂进行复配才能达到良好的增稠稳定效果。最终确定了复配稳定剂的组成及配比:卡拉胶添加量为0.01%、黄原胶的添加量为0.02%。在室温下贮藏20 d后样品的悬浮稳定性很好,这时的Z-均粒径为578.3 nm,属于胶体分散体系,PDI值为0.725,在配比中属于最小值。     

不同亲水胶体对再制奶油奶酪品质的影响

通过研究刺槐豆胶、卡拉胶、海藻酸钠、瓜尔豆胶和黄原胶5种不同亲水胶体对以切达奶酪为原料,直接酸化法得到的再制奶油奶酪品质的影响,来选择较佳的亲水胶体方案。实验结果表明,亲水胶体对样品各方面的性质影响显著,对持水性和持油性的影响尤为明显。本体系适用不凝胶的亲水胶体。黄原胶和刺槐豆胶是最佳的选择,并建议2种胶体单独使用。     

亲水胶体对肉糜凝胶强度和持水性能的影响

将几种不同的亲水胶体复配后应用于低脂肉糜中,通过对肉糜凝胶强度和持水性的测定,筛选出一种复配型亲水胶体作为脂肪替代品。结果表明:复合亲水胶体的最佳配方为大豆分离蛋白2.5%,魔芋精粉1.0%,黄原胶0.2%,卡拉胶0.3%。按此最佳配方添加于肉糜中,添加水量35%,在100℃下加热1.5h,肉糜综合性质较佳。     

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.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.