超临界CO2流体萃取胡椒油工艺条件的研究

建立了超临界流体萃取胡椒油的实验装置，以CO2为萃取剂，考察了萃取压力、操作温度、胡椒颗粒度及CO2流量等因素对胡椒油萃取率的影响，同时考虑设备投资对萃取过程的影响，由此确定了超临界CO2萃取胡椒油的较佳工艺条件：萃取压力22MPa～26MPa，操作温度313K～323K，胡椒颗粒度30目～40目，CO2流量0．3m^3／h～0．4m^3／h，胡椒油累积萃取率为80％～90％。     

超临界CO2萃取芦笋中总黄酮的工艺研究

采用超临界CO2萃取技术对芦笋中的黄酮类化合物进行了萃取研究，运用L9（3^4）正交表系统研究了萃取压力，萃取温度，萃取时间以及夹带剂用量对萃取率的影响。确定了超临界CO2萃取芦笋总黄酮的最佳工艺条件为：温度为70℃、时间为2h、压力为30MPa、夹带剂（75％乙醇）用量为2．0mL／g。此条件下得到总黄酮比率为1．35％，其黄酮得率是常规溶剂乙醇提取法总黄酮得率的2．7倍。     

超临界CO2萃取番茄红素工艺条件的研究

以番茄粉为原料，利用超临界CO2流体萃取技术对番茄红素的提取工艺进行了研究。探讨了萃取压力、萃取温度、萃取时间及夹带剂对番茄红素萃取率的影响，应用高效液相色谱仪对萃取特进行分析检测。采用二次回归正交旋转组合设计，通过计算机分析得出最佳工艺参数为：萃取压力38MPa、萃取温度61℃、夹带剂添加64mL大豆色拉油、萃取时间120min，番茄红素的萃取率为1．18mg/100g.     

超临界CO_2萃取发酵法生产的番茄红素工艺的研究

研究了应用超临界CO2萃取技术,萃取发酵法生产的番茄红素的最佳工艺条件。结果表明,萃取压力30MPa,萃取温度50℃,萃取时间1.5h,CO2流量为25 kg/h,乙醇体积分数90%。     

番茄红素超临界二氧化碳萃取研究

通过单因素和正交试验对番茄红素超临界CO2萃取工艺进行了优化，研究表明，最佳工艺条件为：萃取压力25MPa，萃取时间3h，萃取温度50℃，CO2流量40L／h。     

到临界CO2萃取西瓜中番茄红素研究

本实验研究了超临界萃取西瓜番茄红素工艺,实验表明：在30MPa,55℃,2h,CO2流量为25L／h,加入乙醇,西瓜沉淀干燥物的总提取率为17．7％,番茄红素含量为29．5％。     

苹果籽油的超临界萃取试验研究

应用CO2超临界流体萃取技术对苹果籽油的萃取工艺进行研究，得出最佳萃取工艺条件为：萃取压力30-35MPa、萃取温度30-35℃、CO2流量20～25kg／h、原料破碎度50目、萃取时间90min：利用气相色谱分析了苹果籽油的组成成分，结果表明苹果籽油中不饱和脂肪酸含量为91.81％,其中油酸32．27％，亚油酸59．54％。     

超临界CO2萃取樟树籽油脂的实验研究

对超临界CO2萃取樟树籽油的工艺进行了研究，探讨了萃取压力，萃取温度和CO2流量对樟树籽油萃取的影响，在萃取压力20MPa、萃取温度40℃、CO2流量35kg/h条件下，萃取2h，樟树籽油的萃取率可达94．3％。     

超临界CO2萃取玉米皮纤维脂类物质的研究

采用超临界CO2流体萃取技术脱除玉米皮纤维中脂类物质。通过正交试验方法确定超临界CO2流体萃取的最佳工艺条件为：萃取压力30MPa、萃取温度45℃、萃取时间60min、CO2流量23L／h，脂类物质提取率为5．06％。萃取脂类物质后所得玉米皮纤维颜色乳白，风味纯正，脂肪含量低于0．3％，可作为低热量高膳食纤维食品的添加剂。     

超临界CO2萃取红松子油的研究

研究超临界CO2萃取红松子油的影响因素，在试验条件下，其影响因素次序为萃取压力、夹带剂、萃取温度、萃取时间。最优条件为35MPa，45℃，240min，5％无水乙醇作夹带剂，CO2流量20L／h～25L／h。45oC时，在15MPa和35MPa两种不同的压力下，对比了加入5％无水乙醇作夹带剂与不使用夹带剂时超临界CO2萃取过程中出油量随时间的变化，使用夹带剂后出油量均有提高。     

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.     

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.