草鱼内脏油的精制及阻抑鱼油氧化条件的研究

目的:研究草鱼内脏油精制条件,并比较不同抗氧化剂对鱼油的抗氧化作用.方法:用真空提油法提取粗草鱼内脏油,通过脱胶、脱酸、脱色、脱臭工艺精制鱼油,以过氧化值(POV)和硫代巴比妥酸值(TBARS) 为指标,在60℃条件下,对VC、VE、BHT、PG四种抗氧化剂进行筛选并比较.结果与结论:最佳的精制条件为:利用50%的磷酸脱胶,添加量为油量的1%;用浓度为3.65%的氢氧化钠脱酸,添加量为油量的1.5%;用活性炭和活性白土脱色,二者比例为1:20,添加量为油量的2.1%;在真空度为0.085kPa的条件下脱臭,时间为60min.不同抗氧化剂对鱼油的抗氧化能力为:0.01% PG ＞0.02% BHT＞0.1% VE＞0.2% VE＞0.2% VC.     

深海粗鱼油的精炼工艺研究

对深海杂鱼粗鱼油精炼工艺进行优化,考察了磷酸体积分数、超量碱和活性白土添加量对鱼油酸值、回收率和感官品质的影响,并对精炼鱼油的理化指标及脂肪酸组成进行分析。结果表明:适宜的精炼条件为采用占鱼油质量1%、体积分数80%的磷酸脱胶,脱胶油中加入占鱼油质量1.5%的超量碱和理论碱量的Na OH(4 mol/L)脱酸,脱色选用添加占鱼油质量20%的活性白土;精炼鱼油的理化指标均达到我国水产行业精制鱼油的一级标准(SC/T 3502—2000),酸值(KOH)由(5.52±0.12)mg/g下降到(0.29±0.11)mg/g;精炼工艺对鱼油脂肪酸组成的影响较小,其中二十碳五烯酸和二十二碳六烯酸的总量约占总脂肪酸含量的38%,且分别占多不饱和脂肪酸含量的35.99%和51.59%,品质较优。     

鱼粉加工副产物中鱼油的精炼及其脂肪酸组成分析

对鱼粉加工副产物中鱼油的精制进行研究,得到鱼粉加工副产物中鱼油精炼的最佳工艺：添加1%磷酸（体积分数60%）脱胶,3% NaOH（质量分数12%）溶液脱酸以及15%活性炭脱色,在85 ℃条件下减压蒸馏脱臭10 min。在精炼过程中,鱼油中饱和脂肪酸含量下降,其他脂肪酸含量变化较小。所制备鱼油的理化指标均达到精制鱼油一级要求,其中多不饱和脂肪酸总含量达到0.69 g/mL,二十二碳六烯酸和二十碳五烯酸含量分别为0.229 g/mL和0.121 g/mL。     

鳜鱼内脏副产物中鱼油的精炼及其品质分析

目的:优化鳜鱼内脏粗鱼油精炼工艺,改善鱼油品质。方法:以酸价和过氧化值为响应值,磷酸体积分数、NaOH添加量、活性白土添加量为影响因素,采用Box-Behnken响应面法优化鳜鱼内脏粗鱼油精炼工艺,并对鱼油精炼前后的感官品质、理化指标及脂肪酸组成进行分析。结果:最优的精炼工艺条件为:磷酸体积分数50%,NaOH添加量2%,活性白土添加量15%。在此条件下,精炼鱼油的酸价为(0.94±0.03) mg/g、过氧化值为(0.12±0.01) g/100 g,与预测值基本一致,且模型显著。精炼工艺对鱼油脂肪酸组成及含量的影响较小,精炼后鱼油以不饱和脂肪酸为主,主要为十八碳烯酸(36.73%)和共轭亚油酸(27.02%)。结论:在最佳精炼工艺条件下鳜鱼内脏鱼油的感官品质、理化指标及物理特性等品质特性均得到有效改善。     

真空在罗非鱼油精炼工艺中的应用研究

研究了真空在罗非鱼油精炼工艺中的应用。得到最佳真空精炼工艺参数为:在真空度0.095MPa下进行脱胶、脱酸、水洗、干燥、脱色处理;在70℃下,用质量分数为80%的磷酸溶液进行真空脱胶,磷酸添加量为粗鱼油质量的1.5%,先搅拌20 min,然后静置30 min;在50℃下,用质量分数为20%的氢氧化钠溶液进行真空脱酸,超量碱添加量为理论碱量的4%,脱酸时间20 min;在50℃下,用95℃以上的热水真空水洗3次,每次热水添加量为脱酸鱼油质量的15%;在95℃下进行真空干燥,干燥时间30 min;在70℃下,用质量比为1∶9的活性炭与活性白土混合物进行真空脱色,脱色剂添加量为干燥鱼油质量的5%,脱色时间20 min。梯度降温冬化第一阶段降温速率0.2℃/min,由室温降温至5℃,第二阶段置于冰箱冷藏过夜。成品油理化指标远高于我国水产行业鱼油标准(SC/T 3502—2000)中一级精制鱼油要求。     

鱿鱼内脏粗提油的精制工艺优化及其理化指标分析

本研究采用碱炼法脱酸、活性白土分批脱色对鱿鱼内脏粗提油进行精炼。分别以酸价和脱色率作为脱酸和脱色效果的评价指标,在单因素实验的基础上,运用中心组合设计法优化精制工艺,同时分析测定了精制前后鱿鱼内脏油的相关理化指标。结果表明鱿鱼内脏粗提油的最佳脱酸工艺为:碱液浓度26 °Bé、碱炼温度54℃、碱炼时间26 min,在此脱酸条件下鱿鱼内脏油的酸价为(0.63±0.05)mg/g;最佳脱色工艺为:活性白土添加量3.7%、脱色温度88℃、脱色时间60 min,在此脱色条件下鱿鱼内脏油的脱色率为92.38%±1.25%。精制后鱿鱼内脏油的酸价和色泽达到一级精制鱼油的质量标准,其他各项理化指标达到或接近二级精制鱼油的质量标准。精制后鱿鱼内脏油的多不饱和脂肪酸含量达38.91%,其中EPA和DHA含量分别为12.56%和16.32%。以上结果说明本研究优化的工艺能够对鱿鱼内脏粗提油进行有效的精炼,可用于工业化生产。     

鱿鱼内脏毛油的精制研究及脂肪酸分析

研究以鱿鱼内脏毛油为原料,探索鱿鱼内脏毛油的精制方法,涉及脱胶、脱酸、洗涤、干燥、脱色过程。经过单因素试验,得到精炼鱿鱼内脏粗油的最佳工艺条件为:用磷酸脱胶,用量为油重的1%,浓度为80%;用15%Na OH碱炼,用量为油重的4%;脱色用白土与活性炭质量比为9∶1,添加量为油重的5%,70℃下脱色20 min。在此条件下,得到的精炼油浅黄色透明,略有淡淡鱼油的腥味,相关理化指标都达到精制鱼油标准,GC分析表明其不饱和程度含量高,EPA和DHA含量达34.07%,可作为食品或者饲料添加剂。     

二步提取法中鳡鱼内脏油的浸出工艺优化

以鳡鱼内脏为原料,采用单因素和正交实验设计L9(33)优化熬煮-浸出二步提取法中的浸出工艺参数.结果表明,100℃熬煮6～8min后,鱼渣按料液比2∶1(m/v)加入正己烷,反复提取4次,30min/次,鱼油提取率可达64.17％.鱼油呈棕黄色、浑浊态,有独特的鱼腥味,理化指标达到一级粗鱼油标准.精炼后,成品鱼油呈淡黄色,微浊,有淡鱼腥味;酸价0.07mg KOH/g,碘价140 I2/100g,杂质0.07％,达到精制鱼油一级标准;过氧化值为6.26mmol/kg,不皂化物含量达1.74％,达到精制鱼油二级标准.     

酶法提取沙丁鱼内脏鱼油工艺优化及其品质分析

为提高沙丁鱼加工副产物的利用率,以沙丁鱼内脏为原料,研究5种蛋白酶(胃蛋白酶、木瓜蛋白酶、中性蛋白酶、胰蛋白酶和碱性蛋白酶)对沙丁鱼内脏鱼油提取率的影响,并优选1种蛋白酶作为鱼油提取酶,以鱼油提取率为指标,通过单因素试验和正交试验确定沙丁鱼内脏鱼油提取的最佳工艺条件。对酶法提取的粗鱼油进行精制,对精制鱼油的理化指标和脂肪酸组成进行分析。结果表明：采用中性蛋白酶时,鱼油提取率最高;中性蛋白酶酶解提取沙丁鱼内脏鱼油的最佳工艺条件为料液比1∶1、加酶量1%、酶解时间2 h、酶解pH 7、酶解温度50℃,在此条件下沙丁鱼内脏鱼油提取率可达67.86%;粗鱼油经精制后,达到SC/T 3502—2016精制鱼油的二级标准;精制鱼油中DHA含量为26.57%,EPA含量为2.64%,营养价值较高。     

酶法提取沙丁鱼内脏鱼油工艺优化及其品质分析

为提高沙丁鱼加工副产物的利用率,以沙丁鱼内脏为原料,研究5种蛋白酶（胃蛋白酶、木瓜蛋白酶、中性蛋白酶、胰蛋白酶和碱性蛋白酶）对沙丁鱼内脏鱼油提取率的影响,并优选1种蛋白酶作为鱼油提取酶,以鱼油提取率为指标,通过单因素试验和正交试验确定沙丁鱼内脏鱼油提取的最佳工艺条件。对酶法提取的粗鱼油进行精制,对精制鱼油的理化指标和脂肪酸组成进行分析。结果表明：采用中性蛋白酶时,鱼油提取率最高;中性蛋白酶酶解提取沙丁鱼内脏鱼油的最佳工艺条件为料液比1∶ 1、加酶量1%、酶解时间2 h、酶解pH 7、酶解温度50 ℃,在此条件下沙丁鱼内脏鱼油提取率可达67.86%;粗鱼油经精制后,达到SC/T 3502—2016精制鱼油的二级标准;精制鱼油中DHA含量为26.57%,EPA含量为2.64%,营养价值较高。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

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.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

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.     

Analysis on Economic Indicators from 62 Enterprises in Printing Machinery Industry in Q1 2014

Operation of printing machine industry was still unsatisfactory in the first quarter of 2014.Analysis on operation of printing machine industry.a.Market demand was not strong;sales of product undulated and declined.According to the statistics,the total industrial output value fell by 19.28% in the first quarter of 2014 than the average quarter value in 2013; industrial added value decreased by 4.16%; sales revenue dropped by 22.83%. h. Business operation of enterprises was in poor condition. c. R＆D of new products is an important transformation guarantee for enterprises. d. To take self explore new ways upgrading advantages,and explore new ways.