新型无糖苦瓜酸奶的研制

研究了具有营养保健功能的无糖苦瓜酸奶的加工工艺,结果表明:以鲜苦瓜为原料,用100mg/kg葡萄糖酸锌作为护色剂、1%-β环状糊精作为苦味包埋剂,可制得质量良好的苦瓜汁;采用苦瓜汁∶鲜牛奶=37∶的原料配比、阿斯巴甜0.05%、复合稳定剂0.15%,将保加利亚乳杆菌和嗜热链球菌以11∶混合作为发酵剂进行发酵、接种量3%、发酵温度42℃、发酵时间5h等工艺条件,可得到品质风味优良的新型无糖苦瓜酸奶。     

苦瓜保健果冻工艺技术的研究

本文研究了以苦瓜汁、卡拉胶、魔芋胶、环状糊精为主要原料生产苦瓜保健果冻的生产工艺，通过试验确定了最佳工艺参数。苦瓜汁的适宜用量为6％，将苦瓜块在沸水中烫漂30s后，放入料水比1：3的0．1％柠檬酸 o．05％异抗坏血酸 1％食盐的护色液中，可保持苦瓜汁的色泽。在果冻中添加0．3％的β-环状糊精，配合苦瓜块轻微烫漂，可较好解决产品的苦味问题。试验还确定了苦瓜保健果冻的最佳配方。     

苦瓜生姜复合饮料加工工艺研究

本实验以苦瓜、生姜为主要原料,采用正交设计、感官评价等方法,研究了苦瓜生姜复合饮料的加工工艺。结果表明,在苦瓜汁中添加0.5%β-环状糊精可有效降低其苦味,复合饮料的最佳配方为苦瓜与生姜的原汁比为14:1、0.15%柠檬酸、5%白砂糖。     

杨梅固体醒酒饮料的工艺优化研究

以杨梅汁、葛根、葛花、甘草和菊花为原料,研制出一种醒酒固体饮料冲剂.通过工艺优化试验,得到该醒酒饮料冲剂喷雾干燥的最优参数为进料温度190℃、麦芽糊精量14％、进料速度80 mL/min;得到的成品呈乳黄色,且颗粒均匀,复水时间短,冲剂复水后口味柔和,甜度适中,与原液体饮料的口味十分接近.     

苦瓜汁乳饮料的工艺研究

以苦瓜和牛乳为原料,对苦瓜的脱苦、护色条件及苦瓜汁乳饮料的制备工艺进行研究。结果表明,10%盐溶液浸泡25min脱苦效果最佳,浓度为400mg/kg的异抗坏血酸钠的护色效果最好。最佳配方为,苦瓜汁与牛乳体积比1∶2,白砂糖添加量9.5%,柠檬酸添加量0.75%,复合稳定剂(羧甲基纤维素钠、黄原胶、琼脂以1∶1∶1的比例复合)添加量0.15%。在最佳工艺配方条件下,可制得具有丰富营养、独特风味的苦瓜汁乳饮料。     

苦瓜乳复合饮料的工艺研究

研究了具有营养保健功能的苦瓜乳复合饮料的加工工艺。结果表明:以鲜苦瓜为原料,用100mg/kg葡萄糖酸锌作为护色剂、1%β-环糊精作为苦味包埋剂,可制得质量良好的苦瓜汁;采用鲜牛乳:苦瓜汁=8:2的原料配比,蔗糖9%,复合稳定剂0.15%等工艺条件,可得到品质优良的苦瓜乳复合饮料。     

杨梅固体醒酒饮料的工艺优化研究

为改变市场上醒酒饮料产品大多风味口感不佳,醒酒效果参差不齐的现状,以杨梅汁、葛根、葛花、甘草和菊花为原料,研制出一种醒酒固体饮料冲剂.通过工艺优化试验,得到该醒酒饮料冲剂喷雾干燥的最优参数为料温度190℃、麦芽糊精量14％、进料速度80mL/min.得到的成品呈乳黄色,颗粒均匀,复水时间短,冲剂复水后口味柔和,甜度适中,与原液体饮料的口味十分接近.     

豆奶中加入苦瓜汁生产酸豆奶的工艺研究

以豆奶和苦瓜汁为原料,研究了用保加利亚乳杆菌和嗜热链球菌为发酵剂进行乳酸发酵制作酸豆奶的工艺。经正交试验得到的最佳工艺条件为:在豆水比1∶10的溶液中,加入10%脱脂乳,20%苦瓜汁,8%蔗糖,0.2%复合豆奶稳定剂,接种量4%,41℃下发酵6h,可制得色泽均一、组织细腻、酸甜爽口、香味协调的苦瓜酸豆奶。     

苦瓜复合保健饮料的研制

以苦瓜、胡萝卜、菠萝为主要原料,采用正交设计、感官评价等方法,探讨复合饮料的生产工艺。研究表明:添加0.5%β-环状糊精可有效降低苦瓜汁的苦味,复合饮料的最佳配方为8%苦瓜汁,20%菠萝原汁,10%胡萝卜原汁,0.02%蛋白糖,0.2%柠檬酸。稳定剂选择0.04%CMC+0.01%黄原胶,杀菌条件确定为100℃、10min。     

苦瓜营养豆腐的研制

以苦瓜和大豆为原料研制了苦瓜营养豆腐,其最佳工艺参数:豆浆料水质量比为1∶6,葡萄糖酸内酯添加量0.25%,豆浆苦瓜汁体积比为6∶2。该产品呈淡绿色,具有一定的苦瓜香和纯正的豆香味,并有保健和美容作用,发展前景广阔。     

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.