牡丹籽油亚临界流体萃取工艺优化

采用亚临界流体技术萃取牡丹籽油,通过正交试验对制油工艺进行优化,并对此法所得牡丹籽油的脂肪酸
组成及理化性质进行分析。结果表明,最优萃取工艺条件为萃取温度50 ℃、萃取压强0.5 MPa、每次萃取30 min、
萃取3 次,该条件下牡丹籽出油率达24.16 %。所得牡丹籽油共鉴定出12 种脂肪酸,主要为亚麻酸（45.412 2%）、
亚油酸（38.119 9%）、棕榈酸（11.124 6%）和硬脂酸（3.648 9%）。其理化指标为：相对密度0.901 3、折光指数
1.474 2、酸值3.25 mg KOH/g、碘值175 g I2/100 g、皂化值176 mg KOH/g、过氧化值1.48 meq/kg。     

亚临界萃取文冠果籽油工艺的响应面优化

探讨了亚临界萃取文冠果籽油的工艺条件,通过单因素实验研究原料粒度、萃取温度和萃取时间对提油率的影响,在此基础上,采用Box-Behnken设计响应面实验,优化确定最佳工艺条件。结果表明,在四氟乙烷(R134a)为溶剂、萃取压力1.0 MPa、萃取次数3次下,亚临界萃取文冠果籽油的最佳条件为:原料粒度66目、萃取温度41℃、萃取时间56 min,在此条件下提油率为97.18%。文冠果籽油理化性质测定结果表明,其酸值(KOH)为0.8 mg/g,过氧化值为0.20 g/100 g,总砷含量小于0.01 mg/kg,铅含量小于0.005 mg/kg,溶剂残留未检出,相对密度为0.929 3,折光指数为1.471。利用气相色谱分析文冠果籽油的脂肪酸组成,共鉴定出13种脂肪酸,主要是棕榈酸(6.10%)、油酸(28.77%)、亚油酸(45.62%)、二十碳烯酸(6.78%)、硬脂酸(1.79%),其中不饱和脂肪酸占总组分的81.91%。     

南瓜籽油亚临界流体萃取工艺及成分研究

采用亚临界流体技术萃取南瓜籽油,在单因素试验基础上通过正交试验对工艺条件进行优化,并对此法所得南瓜籽油的脂肪酸组成及理化性质进行分析。结果表明:最优萃取工艺条件为萃取次数4次、料液比1∶5、萃取温度30℃、萃取时间25 min,在此条件下得到南瓜籽提油率为89.12%;所得南瓜籽油共检测出5种脂肪酸,主要为棕榈酸(18.84%)、亚油酸(40.17%)、油酸(29.38%)、硬脂酸(10.67%)和花生酸(0.93%);其理化指标为碘值(I)124.5 g/100 g、酸值(KOH)1.6 mg/g、皂化值(KOH)188.5 mg/g、相对密度0.915。     

石榴籽油低温连续相变萃取工艺优化及其脂肪酸分析

采用低温连续相变萃取技术分离石榴籽油,以油脂得率为指标,通过正交试验L9(3~4)优化萃取工艺,并对石榴籽油理化性质和脂肪酸组成进行分析。结果表明,低温连续相变萃取石榴籽油的最佳工艺条件为:原料颗粒度60目,萃取压力0.5 MPa,萃取温度45℃,萃取时间70 min,解析温度70℃,该条件下石榴籽油得率为15.94%,石榴籽原料含油量16.31%,提取回收率高达97.60%。低温连续相变萃取石榴籽油呈浅黄色半固体膏状物,酸价为3.26 mg KOH/g,过氧化值为0.10g/100g。石榴籽油主要脂肪酸组成为9C,11TR,13TR-十八碳三烯酸甲酯(亚油酸,68.09%)、亚油酸甲酯(9.13%)、十八烯酸甲酯(6.91%)、棕榈酸甲酯(4.73%)、硬脂酸甲酯(3.33%)。     

油莎豆油亚临界丁烷萃取条件优化及产品质量研究北大核心CSCD

以油莎豆为原料,采用亚临界丁烷萃取法提取油莎豆油。以油莎豆粕残油率为考察指标,在亚临界萃取压力0.5 MPa的条件下,通过单因素试验和响应面试验优化亚临界丁烷萃取油莎豆油的工艺条件,并对亚临界丁烷萃取的油莎豆油品质进行了分析。结果表明:油莎豆油的最佳萃取工艺条件为物料粒度0.425 mm(40目)、萃取温度45℃、萃取时间50 min、液固比8∶1,在此条件下萃取1次,油莎豆粕残油率为2.91%。所得油莎豆油酸值(KOH)和过氧化值分别为1.33 mg/g、0.074 g/100 g,不饱和脂肪酸含量高达84.26%,甾醇和V_(E)总量分别为171.43 mg/100 g、201.81 mg/kg。亚临界丁烷萃取法提取油莎豆油粕残油率低,产品质量达到LS/T 3259—2018《油莎豆油》质量指标,是一种值得推广应用的油莎豆油生产工艺技术。     

椪柑籽油提取工艺优化及其抗氧化活性的研究

本研究以椪柑籽为原料,采用响应面法优化压榨及亚临界丁烷萃取工艺,得到椪柑籽油最佳提取条件,并对所得椪柑籽油进行抗氧化活性研究。结果表明压榨法最佳工艺条件为加热时间2 min、微波功率900 w和喷水比例2.10%,出油率达到27.12%；亚临界丁烷萃取最佳工艺条件为萃取次数4次、萃取温度45 ℃、萃取时间43 min,出油率达到10.02%。高效液相色谱分析结果表明,亚临界椪柑籽油中橙皮苷含量(49.60 μg/g)和柚皮苷含量(30.07 μg/g)分别高于压榨椪柑籽油中橙皮苷含量(17.29 μg/g)和柚皮苷含量(28.30 μg/g)。当样品质量浓度为50 mg/mL,亚临界椪柑籽油DPPH自由基清除率为71.81%,ABTS自由基清除率为48.66%,总抗氧化能力为0.123 mmol/L。压榨椪柑籽油DPPH自由基清除率为24.34%,ABTS自由基清除率为15.11%,总抗氧化能力为0.102 mmol/L。因此,亚临界椪柑籽油比压榨椪柑籽油具有更强的抗氧化活性。     

亚临界丁烷萃取澳洲坚果油的工艺及品质研究

为提高澳洲坚果的出油率,采用亚临界丁烷萃取技术提取其油脂,优化温度、时间、料液比、萃取次数等工艺参数,并分析其主要理化指标及脂肪酸组成等品质指标。结果表明,亚临界丁烷萃取澳洲坚果油的最佳工艺参数为:萃取温度45℃、萃取时间15 min、料液比1∶5 g/m L、萃取4次,该条件下澳洲坚果油得率可达80.7%。所制备的油脂品质好,可省去大部分精炼工序;脂肪酸组成以油酸(58.99%)和棕榈油酸(17.59%)为主,并含少量的棕榈酸(9.29%)和硬脂酸(4.15%)。上述结果表明,亚临界丁烷提取澳洲坚果油脂具有操作温度低、产品质量优良的特点。     

固体碱催化合成中碳链脂肪酸聚甘油酯

以聚甘油、樟树籽仁油脂肪酸为原料,固体碱KOH/Al2O3为催化剂,催化酯化合成中碳链脂肪酸聚甘油酯.采用单因素试验研究反应温度、反应时间、聚甘油与中碳链脂肪酸质量比、催化剂用量对酯化率的影响,通过正交试验优化中碳链脂肪酸聚甘油酯的合成工艺.最优合成工艺条件为反应温度220℃、反应时间2.5h、聚甘油与中碳链脂肪酸质量比2∶1、催化剂用量4.5％,该条件下酯化率为87.5％,所得中碳链脂肪酸聚甘油酯的酸值(KOH)、皂化值(KOH)、碘值(Ⅰ)、熔点分别为1.86 mg/g、148.4 mg/g、2.9 g/100 g、47.3℃.     

R134a亚临界流体萃取沙棘籽油的工艺优化及品质评价

研究采用R134a(1,1,1,2-四氟乙烷)亚临界流体萃取沙棘籽油。在原料粒度、萃取时间和萃取温度三个单因素筛选的基础上,以籽油提取率为响应值,对这三个因素进行响应面优化,得到最佳工艺参数:原料粒度32目,萃取时间60 min,萃取温度55℃,在此条件下籽油提取率可达80.7%,所得籽油的碘值、过氧化值、酸价和VE含量分别为(178.83±0.54)g/100 g、(0.151±0.001)g/100 g、(3.412±0.112)mg KOH/g、(198±1.73)mg/100 g,以上指标均满足行业标准(SL 493-2010)的要求,其中碘值和VE含量分别高出行业标准下限27.74%和65%,过氧化值和酸价分别低于标准上限39.6%和77.25%。综上所述,采用亚临界R134a法萃取沙棘籽油具有籽油提取率高、加工成本低及理化品质优良等特点。     

高酸值米糠油萃取脱酸工艺的研究

对高酸值米糠油的溶剂萃取脱酸工艺进行了研究。在以95%乙醇为溶剂、萃取温度30℃、油和溶剂比为1∶1.8(w/w)的条件下萃取3次,可将米糠油酸值从31.02(KOH)/(mg/g)降至4.52(KOH)/(mg/g),通过碱炼可进一步降低酸值至0.23(KOH)/(mg/g)。该工艺可大幅降低脱酸过程中的炼耗,经蒸发脱溶后可直接获得副产品脂肪酸。     

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.