陶瓷膜微滤制备食用级浓缩磷脂的研究

用无机陶瓷膜微滤饲料级大豆磷脂-正己烷混合溶液制备出了杂质含量少、透明程度高的食用级浓缩磷脂。研究了膜孔径、压力、料溶比、温度与膜通量的关系以及不同膜孔径、溶料比、温度对磷脂丙酮不溶物含量、正己烷不溶物含量的影响。实验表明,在40℃,0.20MPa压力下,饲料级浓缩磷脂与正己烷质量比为1∶3的混合溶液用1.2μm孔径陶瓷膜微滤,初始膜通量为110L/(m2·h),微滤后产品中丙酮不溶物含量和正己烷不溶物含量分别为60.20%和0.0082%,符合食用级浓缩磷脂的要求。     

无机陶瓷膜微滤制备食品级大豆浓缩磷脂的研究

采用无机陶瓷膜微滤工艺除去饲料级浓缩磷脂溶液中的杂质,得到含杂量低的食品级浓缩磷脂。选择孔径1.2μm的膜在微滤压力0.15MPa、微滤温度50℃和料液比1∶4(W/V)下过滤磷脂溶液,一次微滤得率为82.3%。用二次微滤工艺,浓缩磷脂得率可以提高到92.5%,得到的食品级大豆浓缩磷脂的主要指标都达到美国同类产品标准。     

无机陶瓷膜对大豆混合油净化的研究

通过无机陶瓷膜进行大豆混合油净化的研究,结果表明:选择30~100 nm无机陶瓷膜,在大豆混合油体积分数27.5%、温度43~50℃、真空0.07 MPa条件下,膜通量为562~1 178 L/(m2·h),除杂效果明显,除杂率达100%;100 nm孔径的无机陶瓷膜反洗通量衰竭较快,并有堵塞现象,不宜用于大豆混合油的净化;30 nm孔径的无机陶瓷膜与50 nm孔径的相比,膜通量小,投资增加,50 nm孔径的无机陶瓷膜过滤具有较合适的效果。     

膜过滤法制备食品级浓缩磷脂

以粗大豆浓缩磷脂为原料,采用无机膜过滤方式制取高质量浓缩磷脂.研究了膜孔径、溶料比、膜过滤温度、物料流速和水分含量对膜通量、丙酮不溶物含量和磷脂得率的影响.实验结果表明,水分含量0.1%,膜孔径0.20μm,溶料比6:1,过滤温度50 ℃,物料流速3 m/s为最佳工艺条件.在最佳条件下,产品中丙酮不溶物含量可达到60%以上,最高可达65%以上;且乙醚不溶物含量可以稳定地控制在0.05%以下.     

陶瓷膜微滤生物柴油的研究

用孔径0.6、0.2、0.1μm陶瓷膜在进口压力0.26MPa、出口压力0.06MPa、温度60℃下微滤粗生物柴油除去其中的皂和游离甘油。结果表明,0.1μm的陶瓷膜滤过液中K、Na、Ca、Mg和游离甘油含量达到欧盟生物柴油标准(EN14214)。用孔径为0.1μm陶瓷膜微滤生物柴油,当浓缩比为4∶1时,膜通量为300L/(m2.h),得到总滤过液中的K、Na、Ca、Mg的含量分别为1.40、1.78、0.81、0.20mg/kg,游离甘油含量为0.0108%。     

鳀鱼蒸煮液陶瓷膜微滤浓缩的研究

本文研究了压力、温度、陶瓷膜孔径、蒸煮液浓度和投料方式对微滤浓缩鳀鱼蒸煮液膜通量的影响。微滤浓缩时,0.45 μm和0.14 μm陶瓷膜对蛋白质的浓缩效率相同,但选用0.14 μm陶瓷膜使整体膜浓缩效率提高;升高温度、压力等均能提高陶瓷膜通量;降低蒸煮液的浓度虽能增大陶瓷膜通量,但降低了蛋白质的浓缩效率。45 ℃浓缩时陶瓷膜通量较高,并且浓缩液的菌落总数、挥发性盐基氮（TVB-N）相对于浓缩因子的增长率最小,丙二醛（TBARS）的增长率与35 ℃、25 ℃相近。因此在温度45 ℃、压力0.3 MPa和选用0.14 μm陶瓷膜的条件下,采用间歇的投料方式作为陶瓷膜浓缩鳀鱼蒸煮液较优的操作条件。陶瓷膜清洗方面,复合清洗剂（1% NaOH+0.05% SDS）在45 ℃的清洗条件下,清洗40 min可使膜通量回复率达到98.99%,比单一清洗剂（1% NaOH）提高22.85%。     

翘鳞伞胞外多糖无机陶瓷膜分离提取工艺优化研究

【研究目的】采用无机陶瓷膜分离提取翘鳞伞胞外多糖,考察不同孔径的膜对膜过程妁影响,优化膜通量影响因素,获得超滤膜分离最佳工艺条件;【方法】以微滤处理后的翘鳞伞发酵液为研究对象,测定了5种不同孔径超滤膜的膜通量以及多糖截留率,采用L9（3^4）正交实验优化了超滤工艺条件;【结果】在5种陶瓷超滤膜中,截留分子量为50kDa的超滤膜最适合于翘鳞伞胞外多糖发酵液分离浓缩,当压力在0．1～0．4MPa,温度在20～40℃时,压力和温度的提高均有利于超滤膜通量的增大,而料液质量浓度的增加对多糖截留率影响较小．【结论】选择50kDa的超滤膜在压力0．3MPa、温度40℃、料液质量浓度0．8g/L的条件下,其膜通量以及多糖截留率最佳。     

混合油状态下膜脱胶工艺的研究

无机陶瓷膜由于其膜材料为化学性质稳定的金属氧化物,能很好地耐受工业己烷和高温条件,适宜于混合油状态下的脱胶分离.本文研究了用孔径为0.05μm、0.02μm、截留分子量为20000dal的无机陶瓷膜超滤大豆混合油,研究了膜通量与时间、压力、温度的关系.超滤结果表明：膜分离不但可以脱除95%以上的大豆磷脂,而且也脱除了部分游离脂肪酸.     

陶瓷膜在卤制品加工废弃液微滤中的应用

探讨了陶瓷膜用于卤制加工废弃液微滤的工艺条件。研究不同预处理方法、膜孔径、操作温度、操作压力等因素对膜通量的影响,并通过正交实验确定微滤的最佳工艺参数为:预处理网筛300目、陶瓷膜孔径0.22μm、操作温度50℃、操作压力0.075 MPa,通过质量分数0.75%NaOH和0.5%柠檬酸复合清洗后,陶瓷膜的通量恢复率可达到94.1%。     

陶瓷膜技术在黄酒生产中的应用

采用错流过滤技术，用陶瓷膜超滤装置对黄酒进行过滤，探讨了超滤时间、压力、温度对膜通量的影响，考查了相关质量指标的变化规律。结果表明，在温度为20℃-25℃、压力为0．2MPa-0．25MPa时，用孔径为0．15μm膜过滤黄酒，其中高分子蛋白质的去除率为56．9％，黄酒的非生物稳定性显著提高，并保持了黄酒的传统风味，且理化指标符合要求。     

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.     

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.     

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.     

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.     

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.