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葡萄籽油和亚麻籽油储藏期间氧化对功能性成分影响 总被引:1,自引:0,他引:1
通过实验研究35℃恒温避光储藏亚麻籽油和葡萄籽油过氧化值、p–茴香胺值、脂肪酸组成和维生素E含量变化,探讨储藏期间油脂氧化劣变对其功能性成分影响。结果表明,经60天储藏,葡萄籽油、亚麻油过氧化值分别达241.30 mmol/kg、248.72 mmol/kg;p–茴香胺值为32.20、104.06;油脂脂肪酸组成不饱和脂肪酸减少0.35%和0.41%,亚油酸和亚麻酸分别降低0.20%和0.09%、0.23%和1.04%,反式脂肪酸含量基本没有变化;维生素E含量显著降低均未检出;储藏期间亚麻籽油氧化对功能性成分影响均大于葡萄籽油。 相似文献
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为比较不同贮藏温度对核桃营养功能成分与品质稳定性的影响,以云南三台核桃为试材,进行了模拟货架期室温(24℃)和0℃低温核桃贮藏试验,分析了核桃氧化稳定性与营养功能成分油酸、亚油酸、亚麻酸、总酚、总黄酮、γ-VE含量的变化.结果表明,室温下贮藏6个月,过氧化值和羰基价较贮藏前分别上升了0.94 mmol/kg、2.48 mmol/kg,油酸、亚油酸、亚麻酸质量分数分别降低了19.5%、14.0%、12.9%,总酚、总黄酮和γ-VE分别降低了34.5%、22.4%和40.1%;0℃下贮藏6个月,过氧化值和羰基价分别上升了0.31 mmol/kg、1.14 mmol/kg,油酸、亚油酸、亚麻酸质量分数分别降低了12.1%、4.3%和4.2%,总酚、总黄酮和γ-VE分别降低了3.2%、12.1%、7.8%.0℃条件下核桃贮藏6个月的营养品质与货架期室温贮藏2个月的品质相当. 相似文献
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选择了不同温度、光照及加入TBHQ抗氧化剂的条件下,以冷榨核桃油储存期间过氧化值和酸值变化为评价指标,对其氧化稳定性进行评价,结果表明:经50d储存,冷榨核桃油酸值和过氧化值都有不同程度的升高,不同温度下过氧化值、酸值升高变化趋势为:50℃>室温25℃避光>5℃;见光条件下的过氧化值、酸值升高变化趋势为:室温25℃见光>室温25℃避光;不同温度下加入抗氧化剂的过氧化值、酸值变化趋势为:50℃>室温25℃避光>5℃;采用Rancimat仪评价几种抗氧化剂提高核桃油的氧化稳定性值结果为:TBHQ>VE>BHT>空白样。 相似文献
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针对烘烤类花生产品抽检的酸价、过氧化值不合格的问题,探究不同储存条件下烘烤类花生的品质,并进行货架期评估。设置不同包装材质、光照、脱氧剂和干燥剂的放置、储存温度条件,以酸价、过氧化值为烘炒类花生品质评价指标,比较它们在不同储藏时间内的变化趋势。结果表明,储存温度对酸价、过氧化值影响均较为明显,在温度、时间相同的储存条件下,以氧化铝涂层复合膜袋包装、袋内放置脱氧剂为最优储存方案,能有效地延缓烘烤类花生酸败过程。采用最优储存方案进行长期稳定性试验和比对试验,样品的感官、理化、微生物指标均符合食品安全国家标准,常温储存可达预计的8个月货架期。 相似文献
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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。 相似文献
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Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates 总被引:2,自引:0,他引:2
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. 相似文献
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Anne Theobald Catherine Simoneau Philippe Hannaert Patrizia Roncari Anna Roncari Thomas Rudolph Elke Anklam 《Food Additives & Contaminants》2000,17(10):881-887
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. 相似文献
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A. Boenke 《Food Additives & Contaminants》2001,18(12):1135-1140
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. 相似文献
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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。 相似文献
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Microbiology of food taints 总被引:2,自引:0,他引:2
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. 相似文献
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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 相似文献
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Jesus Simal-Gandara Miguel Sarria-Vidal Rinus Rijk 《Food Additives & Contaminants》2000,17(9):815-819
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. 相似文献
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H. J. Van Den Top A. Boenke P. A. Burdaspal
J. Bustos
H. P. Van Egmond T. Legarda
A. Mesego A. Mouri o W. E. Paulsch C. Salgado 《Food Additives & Contaminants》2000,17(6):419-433
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. 相似文献
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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 下载免费PDF全文
《造纸信息》2014,(8):80-80
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)" 相似文献
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1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China 下载免费PDF全文
《造纸信息》2014,(8)
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. 相似文献