脱水蔬菜护绿方法的研究

探讨以苦瓜为代表的绿色蔬菜在加工过程中所采用的护绿措施及其护绿效果 ,确定护绿方法和护绿工艺条件。结果表明 ,0 .5cm厚的苦瓜片经 0 .2 0 mol/LNa2 CO3浸泡 1 min后 ,于 85～ 90℃水中烫漂 2 .5min,充分快速冷却后 ,置于 2 0 0 mg/LZn Ac2 0 .3? Cl2 80 0 mg/L Mg Cl2 1 0 0 mg/L EDTA护绿剂中 ,反压处理 1 0～ 2 0 min,沥干后先于 85℃烘 2 h,再于 50℃烘 3h,成品色泽理想。     

出口袋装四季豆加工过程中的护绿研究

对四季豆在加工过程中所采用的护绿措施及其护绿效果进行了研究 ,探讨护绿方法和护绿工艺条件。结果表明 :经过挑选分级的四季豆于 95～ 1 0 0℃水中烫漂 1 .5min左右 ,快速充分冷却后置于 p H1 .5的柠檬酸溶液中 ,室温褪色2 .5h,流动水浸泡去除多余的酸后 ,于 85℃ 30 0 mg/ LCu SO4溶液中浸泡 2 5min,流动水冷却清洗 2 h至水无色 ,随后放入0 .6% Ca Cl2 溶液中浸泡 1 0～ 1 5min,捞起后袋装 ,并加入占总量 40 %的 p H4.2的酸液后封口。于 85～ 90℃水浴杀菌 2 0～30 min。所得产品质地良好 ,色泽理想。     

杏的无硫护色工艺研究

研究杏的无硫护色工艺.结果表明:杏片的厚度、护色工艺影响护色效果.将4mm～5mm杏片浸泡于0.3%β-环状糊精+0.2%葡萄糖酸锌复合液中,热烫2 min,经此处理的杏片仍保持杏原有的橙黄色,具有良好的感官效果.为了防止破碎的杏浆料的褐变,采用90℃下热烫2min以钝化多酶氧化酶(PPO),防止有酶参与的酶促褐变.     

荷花茶制作工艺的研究

本实验是以生产荷花茶为目的 ,研究荷花的护色、护香工艺。实验结果表明最佳护色、护香工艺为 :可食性涂膜 + 0 .5 %柠檬酸 + 0 .0 2 5 %Vc + 0 .0 5 0 %CaCl2 ;浸泡时间为 6min。最佳护味配方为 0 .10 %魔芋葡苷聚糖 + 0 .15 %β -环状糊精。在此条件下干制的荷花色、香、形能基本接近鲜荷花     

板栗果酒生产工艺研究

以板栗为原料，采用液态法发酵生产板栗果酒，结果表明，栗仁：水为1：4，用0．2％SO2护色，浆液灭酶10min，75℃糊化30～40min，添加25％自配复合糖化酶，65℃糖化60min，70℃至碘液反应完全，接种0．2‰酵母，在25℃主发酵6-7d，经陈酿、澄清、调配可得到色、香、味俱佳的优质板栗果酒。     

两种鲜豆荚的速冻保鲜

介绍了两种速冻鲜豆荚的生产工艺，将新剪豆荚及时浸泡于2％～3％的氯化钠水溶液中。以防切口褐变。热烫的适宜温度为96～98℃，时间：青豌豆荚为1．0～1．5min；青刀豆荚为1．0～2．0min，以抑制氧化酶活性。采用单体快速冻结能有效避免慢冻时产生大量冰晶，以防豆荚爆裂，冻结温度为-20～-25℃。时间为8～10min，温度过低会引起豆荚断条。     

软包装清水蘑菇产品护色技术的探讨

本课题采用几种护色剂对软包装清水蘑菇产品进行正交试验，筛选出清水蘑菇产品护色液的最佳配方为：护色剂A：0．2％(以下简称护A)，护色剂B：0．02％(以下简称护B)，护色剂C：0.05％(以下简称护C)。护色效果是：在常态下(普通场所，室温14．30℃)贮藏六个月，蘑菇色泽鲜黄宜人，香味浓郁，汤汁鲜味显著，无任何异常的滋、气味，质地柔嫩而富有弹性，保持了蘑菇原有品质。     

速冻鲜食玉米的冻结规律及工艺优化研究

鲜食玉米在速冻加工中存在水分、色泽、香味及营养损失等问题,严重影响产品的品质。以中糯301、超甜2018为实验材料,对鲜食玉米的冻结规律与速冻工艺进行了研究。结果表明,鲜食玉米冻结时过冷点为-1.2℃,冰点为-0.7℃,最大冰晶生成区范围在-5℃~-1.2℃之间。1%的食盐溶液浸泡鲜玉米穗20 min,可达到驱虫和护色的效果;汽蒸22 min~30 min,能达到较好的烫漂效果;冻藏时间达8个月,玉米仍能保持良好的感官品质和营养品质;速冻玉米在-18℃采用包冰衣的方法可实现0~3个月的短期保藏,采用真空包装能有效降低玉米的失重率,可以保藏6~8个月。     

速冻双孢蘑菇护色工艺研究

为了保证速冻蘑菇良好的色泽,该实验采用五因素四水平正交实验设计,对速冻蘑菇护色和热烫处理条件如护色液的组成、热烫时间等进行了探讨。结果表明,以0.30%的亚硫酸盐(焦亚硫酸钠∶无水亚硫酸钠为1∶2)、0.80%的氯化钠和0.50%的异抗坏血酸钠溶液作为护色液,取1∶3的固液比,浸泡10min,再热烫4min,是速冻蘑菇加工时护色和热烫处理的最优条件。     

火龙果低糖果脯的加工工艺

火龙果脯加工的关键技术是护色、硬化、脱痒喉味、真空渗糖和烘干。实验表明，用0．5％V， 0．5％柠檬酸护色、0．3％生石灰 1．0％明矾硬化、1．0％柠檬酸 0．5％食盐在50℃下脱瘁喉味20min、在真空度0．086～0．089MPa下渗糖25～30min、55—70℃下烘干16～20h制作的火龙果脯，酸甜适口、色泽自然、透明饱满、质量优良。     

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.