婴幼儿营养米粉中营养物质稳定性的研究

通过对婴幼儿营养米粉稳定性的研究,为婴幼儿营养米粉货架期的预测、确定和产品储存以及产品配方、加工技术的改进提供参考。依据化学动力原理设计试验,在温度(37±2)℃,湿度(75±5)%条件下贮藏样品6个月,以加快营养素衰减变质速度,检测各营养素指标,探究婴幼儿营养米粉中营养素的稳定性。结果表明,维生素中的VA、VC、VB1和泛酸的稳定性较差,平均衰减率为47.60%,42.59%,26.70%和28.30%,VD、VE、VB2、VB6、VB7、VB9、VB12和烟酸的稳定性较好。矿物质营养中钠元素的稳定性差,最大衰减为40.00%,钙、铁、锌、钾和磷保持稳定,无明显变化。部分营养素虽在加速试验中呈衰减趋势,但均在合格范围。部分指标可在后期配方设计时进行调整。     

温度及光照对婴幼儿配方乳粉中VA、VD稳定性的影响

为研究不同温度条件下婴幼儿配方乳粉中VA和VD的稳定性,分别考察其在25、40、60 ℃及80 ℃储藏条件下乳粉中的含量变化;通过采用透光和避光2种方式储存的乳粉进行光照试验,研究了光照对乳粉中VA和VD稳定性的影响。结果表明,25 ℃储藏条件下,乳粉中VA和VD含量均无明显变化;40、60 ℃和80 ℃条件下,VA含量有不同程度的降解,而VD无明显变化。光照条件下,乳粉中VA和VD均发生明显降解,其中VA含量在光照1 h后损失达50%,VD含量在光照12 h后损失了将近50%。     

维生素E对β-胡萝卜素纳米乳液性质及其饮料稳定性的影响

为提高β-胡萝卜素的水溶性和稳定性,本研究以吐温80、吐温60和磷脂为乳化剂,维生素E为抗氧化剂制备了纳米乳液。测定了纳米乳液的粒径、透光率、色价、储藏稳定性和应用稳定性。结果显示,维生素E对纳米乳液粒径和透光率有轻微影响,对包埋率和色价没有影响。在25、37 ℃和光照下储藏28 d期间纳米乳液的透光率没有发现明显变化,55 ℃储藏期间透光率呈现下降趋势。在25 ℃和光照下储藏28 d期间色价没有发现明显变化,37和55 ℃储藏期间色价有所降低。不同含量的维生素E均提高了β-胡萝卜素的色价保留率。维生素E的加入显著提高了β-胡萝卜素在酸性和中性饮料中的应用稳定性,且添加量为3%时饮料稳定性最佳。     

木薯蚕蛹中6 种维生素含量分析

目的：分析木薯蚕蛹6 种维生素含量,为木薯蚕蛹的综合利用提供科学依据。方法：高效液相色谱法。结果：木薯蚕蛹中VB1、VB2、VPP、VE的平均含量分别为（0.03±0.00）、（3.14±0.03）、（3.63±0.18）、（3.18±0.20）mg/100 g,VA、VD3未检出。结论：木薯蚕蛹中维生素含量比较丰富,尤其是VB2、VPP和VE。     

不同温度冲调对婴儿配方奶粉中微生物及相关质量的影响

选择国内市场上多个品牌8种婴儿配方奶粉（适合0-6个月婴儿），在21℃，厂家推荐冲调温度（55℃左右）以及沸水（95℃）3种不同温度下冲调，研究了冲调温度对奶粉中微生物的影响。同时对不同冲调温度下奶粉中的部分维生素VA，VB1，VB2，VE，VC损失情况进行了检测，结果表明，除VC在高温时损失明显外，其他几种维生素变化不显著。     

不同储藏条件下全麦片品质的稳定性分析

探讨储藏条件对全麦片储藏期间营养素损失和氧化稳定性的影响,为全麦片的储藏及其货架期的预测提供理论依据。以全麦片为原料,在4℃避光,25℃避光,25℃光照,45℃避光的储藏条件下储藏30 d,分别测定其维生素A含量、维生素E含量、过氧化值、脂肪酸值和酸价等指标,分析比较温度和光照等储藏条件对全麦片营养素和稳定性的影响。结果表明,低温可以显著减少全麦片中的营养素损失和氧化酸败,其中4℃下储藏的全麦片营养素损失最少,氧化稳定性最佳;与其相比在45℃下储藏的全麦片样品维生素A和维生素E分别降低至319.54μg/100 g和96.85 mg/100 g,衰减率分别提高至2.5和3.3倍。储藏温度也显著影响全麦片的氧化稳定性,低温处理使全麦片中的脂肪氧化酸败速度显著下降(p<0.05),在储藏30 d后,相比45℃储藏的样品,在4℃下储藏的样品其过氧化值、脂肪酸值和酸价分别下降了23.26%、87.02%、36.62%。此外,光照也能显著降低全麦片的稳定性。与25℃避光储藏相比,全麦片经过光照储藏30 d后其维生素A和维生素E降低至400.16μg/100 g和180.19 mg/100 g,过氧化值和酸价分别升高至0.16 mmol/kg和0.42 mg/g。综上所述,在4℃避光储藏的全麦片有最好的品质稳定性。     

烹调过程中如何减少维生素的损失

维生素是食物的构成成分。它们都是天然有机化合物，是人体维持生命和健康所不可缺少的要素。烹饪原料在烹调过程中，最易损失的营养素便是维生素。维生素按其理化性质的不同可分为两大类，即脂溶性维生素和水溶性维生素。脂溶性维生素包括VA，VD、VE，VK，水溶性维生素包括VB1(硫胺素)，VB2(核黄素)和VC(抗坏血酸)等。维生素受到高温、氧化、光照等物理、化学因素的影响会遭到破坏而造成损失，且维生素自身会以脂溶或水溶的形式随脂或随水流失。如新鲜蔬菜和水果，它们的细胞     

婴幼儿米粉货架期的预测及货架期内营养成分的变化分析

本文设置了2个外部环境37 ℃ 75% RH和47 ℃ 75% RH对婴幼儿米粉的货架期进行预估,并对米粉货架期内维生素和矿物质的衰减情况进行了分析。结果表明,铁听充氮包装米粉在37 ℃ 75% RH和47 ℃ 75% RH下的货架期分别为210~225和75 d,从而计算得出其在25 ℃ 75% RH下的货架期为722~841 d。货架期内维生素A、泛酸的稳定性最差,货架期最高衰减率分别可达28.96%和24.47%;其次,维生素B₁、维生素B₂、叶酸、维生素E和维生素C的稳定性较差,货架期内最高衰减率分别为18.46%、18.97%、18.53%、13.96%和12.67%;维生素D、维生素B₆、维生素B₁₂、烟酸、生物素以及铁的稳定性较好,在整个货架期内基本无衰减。     

柱切换法液相色谱测定保健食品中的VA、VD、VE

建立柱切换法液相色谱测定保健食品中VA、VD、VE含量的方法。参照GB 5009.82—2016《食品中维生素A、D、E的测定》样品前处理方法,以Agilent Poroshell 120 PFP（4.6 mm×100 mm,2.7 μm）为一维色谱柱,甲醇、水为流动相梯度洗脱,分离VA和VE的4 种异构体,以Agilent Zorbax Eclipse PAH（2.1 mm×100 mm,3.5 μm）为二维色谱柱,甲醇、乙腈为流动相梯度洗脱,分离VD2和VD3。以Agilent Poroshell 120 EC C18（4.6 mm×5 mm,4 μm）为捕获柱,捕获VD。根据VD在一维色谱柱上的出峰起止时间,确定柱切换时间。一维检测波长为325 nm和294 nm,二维检测波长为264 nm。以外标定量法测定VA、VD、VE的含量。结果表明,VA在2.50～50.0 μg/mL、VD在0.10～2.00 μg/mL、VE在5.00～100.0 μg/mL线性范围内线性良好,相关系数均大于0.999。回收率为86%～102%,相对标准偏差为1.5%～4.0%。表明该方法测定准确,适用于保健食品中VA、VD、VE的含量测定。     

婴儿配方乳粉加速试验过程营养素衰减分析

大部分对食品货架期的研究均是以温度为加速因子,在37℃条件下考察了婴儿配方乳粉的保质期。在37℃条件下,脂溶性维生素中的维生素K_1加速6个月出现了轻微的衰减,水溶性维生素中的维生素B_(12)加速6个月的衰减率为15.83%,矿物质在加速试验过程中均未出现明显的衰减,可选择性成分中叶黄素和核苷酸的衰减率分别为18.03%和14.91%。在该加速试验过程中,婴儿配方乳粉的营养素是相对稳定的。     

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.