脲包法富集高纯度红花油亚油酸甲酯的研究

以亚油酸含量 81 74 %的红花油为原料 ,采用先碱性醇解 ,后尿素包合的方法 ,从红花油中富集亚油酸。通过正交试验 ,确定了尿素一次包合法富集高纯度亚油酸甲酯的最佳工艺条件 :混合脂肪酸甲酯∶尿素∶甲醇为 1 0 4∶1∶4 (W/W /V) ,包合温度 - 10℃ ,包合时间 2 4h ,亚油酸甲酯得率 72 95 % ,纯度 99 2 7%。     

尿素包合法提纯油茶籽油中油酸的工艺研究

用尿素包合法对油茶籽油中的油酸进行包合。采用浸出法、直接酸解法和浸出后酸解法分离包合物固相中的油酸。实验结果表明,选用直接酸解法效果较好。尿素包合条件为脂肪酸/尿素/甲醇(W/W/V)比例1∶4∶10,通过包合,油酸的纯度从包合前的66.99%提高到77.96%。     

尿素包合法制备高纯度油酸甲酯的研究

将油茶籽油甲酯化后得到油籽脂肪酸甲酯,再对油茶籽脂肪酸甲酯进行尿素包合,使其中的油酸甲酯含量得到提高。为了进一步提高油酸甲酯的纯度,进行了2次尿素包合优化。试验结果表明:在尿素用量与第2次尿素包合原料的质量比2.75:1、结晶温度0℃、结晶时间12 h、包合搅拌速度650 r/min、包合搅拌时间2 h的条件下进行尿素包合,效果最佳。通过气相色谱对包合后的脂肪酸甲酯产品进行分析,表明油酸甲酯的纯度由78.98%提高到93.53%。     

尿素包合法从葡萄籽油中富集高纯度亚油酸甲酯及包合物表征分析

为提升葡萄籽的使用价值,以葡萄籽油为原料,采用尿素包合法富集高纯度亚油酸甲酯。研究了脂肪酸甲酯与尿素质量比、尿素与95%乙醇质量比、包合时间和包合温度对包合效果的影响,并采用傅里叶变换红外光谱（FTIR）、X射线衍射（XRD）和扫描电子显微镜（SEM）对空白尿素结晶物和包合固形物进行表征。结果表明：制备高纯度亚油酸甲酯的最佳工艺条件为脂肪酸甲酯与尿素质量比1∶2、尿素与95%乙醇质量比1∶4、包合温度5℃、包合时间10 h,在此条件下得到的亚油酸甲酯含量为94.83%,收率为40.41%;FTIR和XRD分析表明,尿素包合反应没有新的官能团生成,且脂肪酸甲酯的包合降低了尿素的结晶度;SEM图像显示,尿素与脂肪酸甲酯形成了六棱体包合物。综上,尿素包合法为富集葡萄籽油中的高纯度亚油酸甲酯的有效方法。     

尿素包合法制备桐油C18不饱和脂肪酸甲酯的工艺优化研究

以桐油通过酯交换反应制得的桐油脂肪酸甲酯为原料,以无水乙醇为溶剂,采用尿素包合法分离其中的C18不饱和脂肪酸甲酯。以C18不饱和脂肪酸甲酯含量和收率为评价指标,探究了尿素用量、无水乙醇用量、包合温度、包合时间对桐油脂肪酸甲酯分离效果的影响。通过正交实验设计优化得到最佳工艺条件。对桐油C18不饱和脂肪酸甲酯的溶剂性能进行了测定。结果表明,尿素用量是影响C18不饱和脂肪酸甲酯含量的主要因素,C18不饱和脂肪酸甲酯制备最佳工艺条件为尿素与桐油脂肪酸甲酯质量比1∶1、无水乙醇体积与桐油脂肪酸甲酯质量比5∶1、包合温度5℃、包合时间18 h,在此条件下C18不饱和脂肪酸甲酯含量可达99. 28%,收率为54. 93%。得到的桐油C18不饱和脂肪酸甲酯的闪点(190℃)、沸点(320℃)高,有机挥发物未检出,贝壳松脂丁醇值(KB)为59,证明其是一种环境友好型溶剂。     

尿素包合法分离麻疯树籽油脂肪酸甲酯的研究

研究了尿素包合法分离麻疯树籽油脂肪酸甲酯中饱和脂肪酸甲酯和不饱和脂肪酸甲酯的工艺条件.结果表明:采用95％乙醇作助溶剂,尿素与脂肪酸甲酯的质量比0.75∶1,包合温度10℃,包合时间20 h,经一次尿素包合后不饱和样品中不饱和脂肪酸甲酯相对含量从原料中的75.88％增加到95.95％;饱和样品中饱和脂肪酸甲酯的相对含量从原料中的23.85％增加到65.73％;二次包合后得到不饱和样品中不饱和脂肪酸甲酯的相对含量增加到98.92％.     

脲包法富集高纯度红花油亚油酸甲酯的研究

以亚油酸含量81．74％的红花油为原料，采用先碱性醇解，后尿素包合的方法。从红花油中富集亚油酸。通过正交试验，确定了尿素一次包合法富集高纯度亚油酸甲酯的最佳工艺条件：混合脂肪酸甲酯：尿素：甲醇为1．04：1：4(W／W／V)，包合温度-10℃，包合时间24h，亚油酸甲酯得率72．95％，纯度99．27％。     

尿素包合法分离油酸甲酯顺反异构体的研究

以顺反混合的油酸甲酯异构体为原料,采用尿素包合法对其顺、反式异构体进行分离.分别考察了油酸甲酯、尿素与甲醇质量比,包合温度,降温速率,包合时间等因素对分离效果的影响.确定最优分离条件为:油酸甲酯、尿素和甲醇质量比1:2:10,包合温度30℃,降温速率30℃/h,包合时间5 h.在此条件下,顺式油酸甲酯纯度可达到96.52%,回收率为47.99%,同时顺式油酸甲酯产品中不含反式油酸甲酯.     

元宝枫油中神经酸乙酯的分离提纯

将元宝枫油制成混合脂肪酸乙酯,分别利用多级分子蒸馏提纯和分子蒸馏与尿素包合法相结合提纯神经酸乙酯得到高含量的神经酸乙酯产品。六级分子蒸馏直接提纯神经酸乙酯,得到神经酸乙酯含量为78.35%的产品。二级分子蒸馏与尿素包合法相结合时,分子蒸馏脱除甾醇、维生素E、C16、C18、C20及部分C22脂肪酸乙酯,得到神经酸乙酯与芥酸乙酯比例为1∶1的初级产品,再在m(脂肪酸乙酯)∶m(尿素)∶V(甲醇)为1∶5∶35、包合温度35℃、包合时间8 h条件下,经过二次尿素包合处理,可得到神经酸乙酯含量为66.21%的产品。     

棉籽油脱臭馏出物中脂肪酸甲酯化工艺研究

棉籽油脱臭馏出物中含有40%-80%的游离脂肪酸,对这部分脂肪酸的甲酯化进行了研究。考察了甲醇用量、催化剂用量、酯化温度、酯化时间对脂肪酸甲酯化的影响。结果表明,脂肪酸甲酯化优化条件为甲醇/原料为2∶1(V/W),催化剂/原料为0.005∶1(V/W),酯化温度65℃,酯化时间3 h;在此条件下脂肪酸甲酯化率达到98%以上。     

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.     

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.     

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.     

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.