南瓜绿豆复合饮料的研制

以南瓜和绿豆为主要原料,采用多种酶对原料进行水解,生产一种营养丰富、口味独特的新型复合饮料。通过单因素实验和正交试验得出:1.南瓜复合酶解最佳工艺参数为:纤维素酶0.4%、果胶酶0.05%、酶解pH4.5、酶解温度50℃、酶解时间2.0h;2.α-淀粉酶水解绿豆淀粉最佳工艺参数为:α-淀粉酶0.2%、酶解pH6.0、酶解温度60℃、酶解时间2.0h;3.木瓜蛋白酶水解绿豆蛋白最佳工艺参数为:木瓜蛋白酶0.05%、酶解pH6.5,酶解温度60℃、酶解时间2.0h;4.南瓜绿豆复合饮料最佳配方为:南瓜汁∶绿豆汁(体积比)为4:6,白砂糖12%、柠檬酸0.1%,食盐0.04%。     

澄清型黄菇娘果汁饮料的工艺研究

目的研究澄清型黄菇娘果汁饮料的制备工艺。方法果汁在制备中采用果胶酶进行酶解,通过单因素试验和正交试验确定果胶酶的最佳工艺参数。同时利用柠檬酸、蔗糖和黄原胶对果汁进行调配,试验采用综合评分法,根据感官品评打分确定产品的最佳配方。结果在果胶酶的最佳工艺参数(酶浓度0.04 g/L、酶解温度40℃、酶解时间2 h)下,果汁出汁率和透光率最高,分别为88.5%和67.1%;澄清型黄菇娘果汁饮料的最佳配方为柠檬酸0.2%,蔗糖14%,黄原胶0.15%,此时饮料酸甜可口、澄清透明,并具有浓郁的果香味。结论该研究可为发展以黄菇娘为原料的深精加工产品奠定一定的理论基础。     

香蕉果酒工艺的研究

以香蕉为原料,采用全发酵法研制具有保健功能的香蕉果酒.单因素试验和正交试验结果表明,其最佳工艺条件为:热烫温度为100℃,热烫时间为4～5 min;NaHSO3的添加量为0.08‰;酶解条件为:酶制剂的添加量为0.04%,酶解温度为45℃,pH值为5,酶解时间为2 h.发酵的最佳工艺条件为:接种量为果汁的10%:0.5%(葡萄酒酵母:异常汉逊酵母)的酵母液,外观糖度18%,发酵温度为28℃,发酵时间为5 d.     

果胶酶酶解库尔勒香梨果汁工艺条件优化

通过试验得出:香梨汁中果胶含量0.4%,最佳酶制剂为液态Pectinex BE XXL;并通过单因素对比试验初步确定库尔勒香梨果汁酶解的工艺条件,通过正交试验优化工艺参数,确定果胶酶酶解库尔勒香梨果汁的最佳工艺组合:酶制剂用量为120 mL/t,温度40℃,时间2 h,最适pH为5～5.5。     

梨果汁加工中酶解工艺的研究

以寒地特色梨为研究对象,在单因素实验的基础上,采取正交实验设计,系统研究了梨果汁最佳酶解工艺条件。研究结果表明:加酶量、酶解温度、酶解时间对梨果汁品质有不同程度的影响;最佳酶解工艺条件为:酶解温度50℃,果胶酶添加量3g/kg,酶解时间2h。     

黑莓果蔬汁加工工艺研究

比较了黑莓离心式和压榨式榨汁法制取果汁,用正交试验法探讨了果汁酶解的最佳工艺条件,比较了4种果汁澄清法和14种澄清剂的澄清效果,并复配成稳定的果蔬汁饮料。结果表明:黑莓以离心式榨汁效果较好;最佳酶解条件为酶浓度为0.06%、温度27℃、时间4h、pH为3.13;复合澄清剂使用浓度为≥0.050%,稳定剂Ⅱ使用浓度为0.015%。     

菠萝蜜果汁加工工艺的研究

以成熟的菠萝蜜果实为原料,采用单因素和正交试验,研究了澄清型菠萝蜜果汁的酶解工艺条件及调配方法。结果表明:用果胶酶酶解菠萝蜜果汁有明显的澄清效果,酶解菠萝蜜果汁的优化工艺条件为酶解温度50℃、酶解时间2.5h、果胶酶用量0.1%;酶解后的菠萝蜜果汁的最佳配方为糖度20°Bx、柠檬酸0.1%、抗坏血酸0.06%。     

酶法黑米饮料的工艺研究

该文研究了酶法黑米饮料的工艺参数和稳定性。正交试验结果表明,液化型淀粉酶液化黑米淀粉的最佳条件是:温度60℃、pH值6.0、酶浓度0.1%和酶解时间1h;糖化型淀粉酶糖化黑米糊精的最佳条件是:温度50℃、pH值5.0、酶浓度0.3%和酶解时间2h;木瓜蛋白酶酶解黑米蛋白质的最佳条件是:温度50℃、pH值6.0、酶浓度0.15%和酶解时间1.5h。通过感官评定法确定黑米饮料适宜的条件,即稀释倍数为3,糖度为10%和pH5.5。黑米饮料对光、热、冷的稳定性的研究表明,黑米饮料对冷稳定,对热不太稳定,对光不稳定。     

正交实验优化酸樱桃果汁酶解工艺研究

以酸樱桃为原料,在单因素实验的基础上,采取正交实验设计,研究了酸樱桃果汁最佳酶解工艺条件。结果表明:果胶酶在酸樱桃果汁加工中的最适添加量为1.6mL/kg,酶解时间为3.5h,酶解温度为55℃。用此工艺生产的酸樱桃果汁,出汁率为87.17%,浊度为1.25NTU。从各因素对果汁加工的影响来看,酶解温度>酶添加量>酶解时间。     

应用神经网络优化芒果果汁的酶解工艺

为研究酶解条件对芒果果汁得率的影响,在单因素的基础上建立了芒果果汁酶解工艺的神经网络模型,并对其工艺参数进行了优化。研究结果表明:果胶酶用量0.007%、纤维素酶用量0.001%、酶解温度40.6℃、酶解时间60min为最佳酶解工艺参数。此时芒果带皮果汁得率为80.48%,去皮果汁得率为66.47%,提高14.01%,且带皮果汁品质变化较小,可以接受。本研究为芒果果汁生产工艺改进提供参考。     

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.     

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.