不同方法提取浒苔膳食纤维的效果比较

目的:以浒苔为原料,对浒苔膳食纤维提取工艺条件进行探讨;方法:选用正交实验设计,分别利用碱处理、酶碱结合处理两种方法提取浒苔膳食纤维,并对两种方法的效果进行了比较;结果:碱处理法提取膳食纤维的最佳条件为:60g/L氢氧化钠溶液,在70℃条件下处理90min,膳食纤维含量为80.21%,膨胀力和持水力分别为6.50mL/g和541%;酶碱结合法提取膳食纤维的最佳条件为:蛋白酶用量1500u/g,纤维素酶用量80u/g,在45℃,pH6下处理1.5h,膳食纤维含量为83.24%,膨胀力和持水力分别达到18.20mL/g和1230%。结论:用酶碱结合提取膳食纤维效果明显好于碱处理。     

茭白壳膳食纤维提取工艺及性能的研究

以芟白壳为原料,采用化学法制备可溶性膳食纤维和不溶性膳食纤维.正交实验结果表明,可溶性膳食纤维提取的最佳工艺条件为:pH2.0、温度80℃、时间90min.不溶性膳食纤维提取的最佳工艺条件为:碱解时NaOH浓度1.0mol/L、料液比1:20(g/mL)、温度60℃、时间60min;酸解时pH3.0、温度60℃、时间120min,其溶胀性为4.34mL/g,持水力为8.11g/g.     

豆渣水不溶性膳食纤维提取工艺研究

本文以豆渣为原料,研究了酸碱处理法提取水不溶性膳食纤维的最佳提取工艺条件.研究结果表明,制取水不溶性豆渣膳食纤维的最佳酸碱处理条件为,碱用量5 mL/g,碱处理温度40 ℃,碱处理时间80min;酸用量4 mL/g,酸处理时间80min.产品中膳食纤维含量达78.3%.     

野山杏果肉不溶性膳食纤维的提取特性研究

以新疆野山杏为原料,采用酸法、碱法和酸碱共处理法三种化学方法提取不溶性膳食纤维,通过正交实验对影响酸法、碱法、酸碱共处理法三种提取不溶性膳食纤维工艺的主要因素进行了比较研究,并比较其性能特性,获得了三种化学方法提取野山杏果肉不溶性膳食纤维的最佳工艺参数,酸法提取的最佳工艺为：料液比1∶10,酸液浓度3%,提取温度30℃,提取时间80min,在此工艺条件下不溶性膳食纤维的得率为25.4%,持水力为12.0g/g,溶胀性为6.5mL/g;碱法提取的最佳工艺为：料液比1∶10,碱液浓度10%,提取温度30℃,提取时间20min,在此工艺条件下不溶性膳食纤维的得率为24.7%,持水力为13.36g/g,溶胀性为7mL/g;酸碱共处理法最佳工艺参数为：碱处理料液比1∶10,碱处理时间30min,碱浓度10%,酸处理料液比1∶10,酸处理时间90min,在此工艺条件下不溶性膳食纤维的得率为16.5%,持水力为33.2g/g,溶胀性为10.4mL/g。     

从麦麸中提取水不溶性膳食纤维的研究

以麦麸为原料,采用化学法提取麦麸中水不溶性膳食纤维。通过单因素试验和正交试验确定麦麸中水不溶性膳食纤维的最佳工艺条件。结果表明碱作用提取的最佳工艺条件为:碱的浓度为4%、处理温度为70℃、处理时间为75 min;酸作用的最佳工艺条件为:酸的浓度为2%、处理温度70℃、处理时间120 min。依据碱与酸作用的最佳工艺条件进行试验,不溶性膳食纤维的得率为18.12%。提取得到的膳食纤维膨胀力、持水力分别为5.43 mL/g和8.62 g/g。     

一种复合抗氧化果蔬酵素的开发及活性研究

以甘草渣为原料,用水浴加磁力搅拌方法辅助,分别对可溶性和不溶性膳食纤维进行碱提,利用单因素试验和正交试验对提取条件进行优化,确定最佳提取工艺为:料液比1∶9(g/mL)、提取温度40℃、提取时间80 min、氢氧化钠浓度6%时,不可溶膳食纤维得率最大为81.33%;料液比1∶10(g/mL)、提取温度80℃、提取时间80 min、氢氧化钠浓度7%时,可溶膳食纤维得率最大为8.33%。采用理化分析方法,对提取物进行功能特性的测定,测定结果为:不可溶膳食纤维的持水力为3.73 g/g,膨胀力为5.00 mL/g;可溶膳食纤维的溶解度为0.02 g/mL,膨胀力为0.50 mL/g。该研究为提取膳食纤维提供一条新途径,为甘草渣的再利用提供一种新思路。     

碱解醇沉法提取玉米种皮中水溶性膳食纤维

以玉米种皮为原料,采用碱解醇沉的方法,对玉米种皮中水溶性膳食纤维提取工艺进行研究。结果表明,其最佳碱解工艺为碱解时间30 min,碱解温度50℃,氢氧化钠质量分数为1%;最佳醇沉条件为料醇比为1∶2(g/mL),醇沉时间30 min,醇沉温度40℃,制得的膳食纤维品质好。     

马铃薯渣中膳食纤维提取工艺的优化

目的:以马铃薯渣为原料,探究提取马铃薯渣中膳食纤维的最佳工艺条件。方法:通过生物法-酶法、超声波裂解、高速剪切等技术提取马铃薯渣中所含的膳食纤维,通过单因素试验和正交试验分析试验数据。结果:提取膳食纤维的最佳工艺条件为酶解p H为5、酶解温度45℃、酶添加量30U/g、酶解2.5h。结论:本研究膳食纤维的提取率达25.87%,并测得持水力和膨胀力分别为7.1g/g、7.5mL/g,该工艺条件可有效提取马铃薯渣中的膳食纤维。     

酶法提取胡萝卜皮渣可溶性膳食纤维的工艺研究

以胡萝卜皮渣为原料,采用酶法提取可溶性膳食纤维,探讨加酶量、酶解时间、酶解温度及pH对膳食纤维得率的影响。通过正交试验确定制备胡萝卜皮渣膳食纤维的最佳工艺条件为:纤维素酶添加量为1.2%,酶解温度60℃,酶解pH 4,酶解时间80 min,此条件下胡萝卜皮渣可溶性膳食纤维得率达5.32%,持水力和膨胀力分别为5.25 g/g和5.30 mL/g。     

盐生植物碱蓬制备膳食纤维的工艺优化研究

以盐生植物碱蓬提取叶蛋白后的残渣为原料,采用酶解处理和碱处理相结合的方法,研究得到了碱蓬高活性膳食纤维的最佳提取工艺。所得碱蓬膳食纤维的膨胀力达9.7mL/g,持水力达515%,其功能性质优于小麦麸皮膳食纤维。     

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.