油脂复合抗氧化剂抗氧化协同增效作用的研究

以易氧化酸败的核桃油为试验原料，取等量的9组样品，将抗氧化剂TBHQ、PG、BHT、VE及增效剂柠檬酸、抗坏血酸(VC)分别以不同的组合方式和配比添加到上述9组样品中，然后与空白样一起利用Schall烘箱法每隔24h测一次过氧化值(POV)，比较它们的氧化稳定性。试验结果表明：添加0．02％TBHQ、0．01％PG和0．015％VC复合抗氧化剂的油样(在60℃通风条件下贮藏17d)的过氧化值最低为0．75meq／kg，经计算其在20℃存储保质期可达20个月以上。     

几种抗氧化剂对核桃油抗氧化性能的研究

用schhal烘箱法研究了几种不同的抗氧化剂及增效剂对核桃油的抗氧化性能，结果表明：特丁基对苯二酚（TBHQ）的抗氧化性能最好，抗坏血酸和柠檬酸均是TBHQ和BHT（2，6－二叔丁基对－甲酚）的良好增效剂，二者都能显著提高TBHQ和BHT的抗氧化性能，选用TBHQ和柠檬酸复合，TBHQ与抗坏血酸复合作为核油的抗氧化剂，可使核桃油在20℃下的贮藏时间从1．9个月分别延到19．9个月和25．9个月。研究结果还表明效果较好的抗氧化剂与效果较差的抗氧化剂复合时具有牵制作用。     

油脂复合抗氧化剂抗氧化协同增效作用的研究

以易氧化酸败的核桃油为试验原料 ,取等量的 9组样品 ,将抗氧化剂TBHQ、PG、BHT、VE 及增效剂柠檬酸、抗坏血酸 (VC)分别以不同的组合方式和配比添加到上述 9组样品中 ,然后与空白样一起利用Schall烘箱法每隔 2 4h测一次过氧化值 (POV) ,比较它们的氧化稳定性。试验结果表明 :添加 0 0 2 %TBHQ、 0 0 1 %PG和 0 0 1 5 %VC 复合抗氧化剂的油样 (在 6 0℃通风条件下贮藏 1 7d)的过氧化值最低为 0 75meq/kg ,经计算其在 2 0℃存储保质期可达 2 0个月以上     

不同抗氧化剂协同效应对花生油稳定性的影响

以过氧化值(POV)作为油脂稳定性的评价指标,采用Schaal烘箱法,研究了TBHQ、BHA、BHT及复合抗氧化剂对花生油稳定性的影响.结果表明,复合抗氧化剂的抗氧化效果优于单一抗氧化剂的,柠檬酸对抗氧化剂有协同增效作用,花生油中添加0.015%TBHQ、0.005%BHT和0.01%柠檬酸抗氧化效果显著.     

精制核桃油生产工艺及其氧化稳定性的研究

研究了利用物理压榨法制备核桃油及其精炼工艺，然后取等重的9组样品，分别添加不同的抗氧化剂TBHQ、PG、BHT、VE及增效剂柠檬酸、抗坏血酸(Vc)，与空白样一起利用Schaal烘箱法每隔24h测一次过氧化值(POV)，比较它们的氧化稳定性。试验结果表明：焙炒、脱酸、脱胶是精制核桃油的关键工序，其工艺条件依次为：焙炒温度130℃、时间30min；碱法脱酸：碱液浓度11％、碱炼初温40℃。加碱量为理论碱量和超碱量之和；磷酸脱胶：油重0．2％的85％磷酸、3％的水、温度保持在60℃；添加0．02％TBHQ、0．01％PG和0．015％Vc复合抗氧化剂的油样(在60℃通风条件下贮藏408h的过氧化值最低为0．75meq／kg，国家标准规定过氧化值≤10nmeq／kg，经计算其在20℃存储保质期可达22个月以上。     

核桃油自氧化及其抗氧化的实验研究

以过氧化值(P0V)为指标研究了温度、时间对核桃油自氧化过程的影响及添加抗氧化剂对核桃油抗氧化性能的影响。结果表明,温度、时间对核桃油的氧化过程有高度显著的影响。TBHQ对核桃油具有较好的抗氧化性能,抗坏血酸和柠檬酸对TBHQ均表现出较强的协同抗氧化效应,且抗坏血酸的协同抗氧化性优于柠檬酸。使用0.015％TBHQ+0.01％柠檬酸或0.015％TBHQ+0.01％抗坏血酸为核桃油的抗氧化剂,可使核桃油在15℃下的贮藏期从2.9个月分别延长至29.8个月和38.9个月。     

非洲山毛豆油抗氧化稳定性研究

采用Schaal烘箱法,以过氧化值(POV)为指标,研究不同抗氧化剂种类以及质量对山毛豆油抗氧化稳定性的影响。结果表明,TBHQ对山毛豆油具有良好的抗氧化效果,柠檬酸、抗坏血酸、植酸对TBHQ和BHT复合而成的抗氧化剂表现出较强的抗氧化协同增效作用,协同作用强弱依次为Vc>植酸>柠檬酸;添加0.0150%TBHQ+0.005%BHT+0.01%Vc复配而成的抗氧化剂,可使山毛豆油在20℃条件下的预期贮藏时间从不到4个月延长至13个月。     

抗氧化剂对蘑菇酱抗氧化性能的影响

采用schhal烘箱法,以过氧化值和酸价为指标研究了不同抗氧化剂对蘑菇酱抗氧化性能的影响。结果表明:相同添加量下,TBHQ对蘑菇酱抗氧化效果最好,但是0.02%TBHQ抗氧化效果不如0.015%TBHQ和0.005%BHT复配的抗氧化剂,抗坏血酸和柠檬酸均对复合抗氧化剂有较强的抗氧化协同增效作用,抗坏血酸的抗氧化协同增效作用优于柠檬酸。因此选用0.01%Vc+0.015%TBHQ+0.005%BHT作为蘑菇酱的抗氧化剂,可使蘑菇酱在20℃条件下的贮藏时间从256 d延长到576 d。     

脂溶性茶多酚对火麻仁油的抗氧化作用研究

以过氧化值(POV)作为油脂氧化程度的评价指标,采用Schaal烘箱法,研究天然抗氧化剂脂溶性茶多酚(LTP)在火麻仁油中的抗氧化作用,并比较LTP与合成抗氧化剂叔丁基对苯二酚(TBHQ)、二丁基羟基甲苯(BHT)在火麻仁油中的抗氧化效果。结果表明:LTP在火麻仁油中具有良好的抗氧化作用,且抗氧化效果与添加量有关,最适添加量为100 mg/kg。在相同添加浓度(100 mg/kg)条件下,经7 d 60℃强化氧化后,LTP、TBHQ及BHT对火麻仁油过氧化值抑制率分别为50.9%,75.7%和11.2%。     

延长花生蛋白粉保质期的研究

研究了采用添加抗氧化剂、抗氧化增效剂、充氮包装等方法延长花生蛋白粉的保质期.通过加速储藏试验,测定过氧化值和酸价确定保质期.结果表明,添加TBHQ0.008%+柠檬酸0.04%配合充氮包装,在60 ℃条件下贮藏24 d时过氧化值为3.15 mmol/kg、酸价为0.604 mg/g,均不超过国家标准,相当于20℃保质期12个月.     

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.