响应面法优化茶渣水不溶性膳食纤维的提取及性能研究

以石阡苔茶茶渣作为实验材料,碱提法对水不溶性膳食纤维进行提取。采用Design-Expert V8.0软件中的Box-Behnken(BBD)中心组合原理设计响应面实验,考察浸提温度、料液比、碱浓度、浸提时间对水不溶性膳食纤维提取率的影响,优化提取工艺,结果表明:优化的最佳提取工艺条件为:浸提温度32.6℃、碱浓度0.2mol/L、浸提时间50min、料液比1∶13.5(g/m L),茶渣中水不溶性膳食纤维的提取率为78.66%;性质研究的结果表明:提取得到水不溶性膳食纤维的持水力为183.92%,溶胀度为2.83m L/g。由此可知,响应面法优化提取水不溶性膳食纤维具有时间短、能耗低、提取率高等特点。     

响应面法优化火棘水不溶性膳食纤维提取工艺

以火棘果为原料,采用碱水解法提取膳食纤维,通过单因素试验和响应面分析,探讨碱液质量分数、浸提时间、浸提温度和液料比对火棘水不溶性膳食纤维提取率和纯度的影响,并对提取工艺条件进行优化。结果表明,碱水解法提取火棘膳食纤维的最佳工艺条件为碱液质量分数1.00%、浸提时间3.00h、浸提温度77.8℃、液料比17:1(mL/g),在此工艺条件下水不溶性膳食纤维的提取率56.89%、纯度达到92.74%,表明该工艺可行。     

野生阳荷水不溶性膳食纤维的提取及性能测定

以梵净山野生阳荷作为实验材料,应用酸碱结合法制备阳荷水不溶性膳食纤维。采用L9(34)正交表进行实验设计,考察料液比、碱浓度、浸提温度、提取时间对水不溶性膳食纤维提取率的影响,优化水不溶性膳食纤维的提取条件,得出水不溶性膳食纤维的佳提取工艺为:料液比1∶45、碱浓度0.25 mol/L、浸提温度52℃、提取时间100 min,在此优化条件下,IDF的提取率为90.73%,提取得到的IDF溶胀度为8.6 mL/g。持水力为2.315 g/g。研究结果表明,梵净山野生阳荷是提取水不溶性膳食纤维的良好原料。     

花生壳不溶性膳食纤维提取工艺的研究

为了促进花生加工副产品的高值化利用,以花生壳为原料,应用酸碱结合法制备花生壳不溶性膳食纤维。通过对碱的质量分数、碱处理温度、碱处理时间、碱用量、酸处理温度、酸处理时间与酸液用量7 个影响因素进行单因素及正交试验,获得了花生壳不溶性膳食纤维的最佳工艺条件。结果表明,3g 花生壳粉在碱的质量分数4% 的碱液60mL、恒温水浴40℃条件下处理30min、然后用60mL 酸液恒温水浴60℃处理90min,不溶性膳食纤维的提取率为86.44%,纯度为91.13%,综合得分为88.01。     

花生壳膳食纤维提取工艺的研究

以花生壳为研究对象,通过一系列单因素实验、正交试验和方差分析的方法,着重对花生壳挤压预处理工艺条件、可溶性膳食纤维提取工艺条件和不溶性膳食纤维的提取工艺条件进行了研究,研究结果表明:花生壳挤压预处理的工艺条件为:物料含水量为20%、挤压温度为170℃、螺杆转速为180r/min;花生壳中可溶性膳食纤维提取的最佳工艺条件为:p H为3、提取温度为85℃,提取时间为2h;花生壳中不溶性膳食纤维提取的最佳工艺条件为:α-淀粉酶加酶量为0.5%、反应p H为6.5、反应温度为65℃、反应时间为50min。在上述工艺条件下制备的花生壳膳食纤维产品中,可溶性膳食纤维含量达到18.1%,不溶性膳食纤维含量达到80.7%。     

杨梅渣膳食纤维提取工艺

以杨梅渣为原料,连续提取水溶性和不溶性膳食纤维,在单因素试验基础上,通过正交试验优化提取工艺条件。试验表明,适宜水溶性膳食纤维提取工艺为:以柠檬酸为浸提剂,料液比(g∶mL)1∶10,pH值2.0,90℃提取75 min,在此条件下提取率达58.62%。适宜的不溶性膳食纤维提取工艺为:料液比(g∶mL)1∶12.5,pH值2.5,60℃提取90 m in,在此条件下提取率达61.25%。所制备的不溶性膳食纤维持水力为570.6%、溶胀性为6.5 mL/g,功能特性良好、生理活性突出。     

山楂中水不溶性膳食纤维提取工艺的优化

以新鲜山楂果实为原料,采用酶化学法提取山楂果实中的水不溶性膳食纤维,通过单因素试验和正交试验优化工艺条件。结果表明,当碱加入量0.50%(样品质量分数),碱解温度45℃,液化淀粉酶用量为0.10%(样品质量分数),酶解时间35 min时,得到的水不溶性膳食纤维纯度高,总杂质去除率为97.8%,水不溶性膳食纤维的提取率为3.52%。所提取的水不溶性膳食纤维持水力为5.27 g/g、膨胀力为5.10 mL/g。     

响应面法优化麦麸蛋白质和膳食纤维的提取工艺

研究麦麸中蛋白质、水不溶膳食纤维、水溶膳食纤维等功能成分的提取工艺。以麦麸为原料,采用醇碱提取-盐析的方法同时提取麦麸蛋白和水溶性膳食纤维,利用α-淀粉酶去除淀粉提取水不溶性膳食纤维。在单因素试验基础上,利用响应面分析法优化提取工艺参数。结果表明,麦麸功能成分的最佳提取工艺参数为酶添加量270U/g、酶反应温度56℃、酶反应料液比1:12(g/mL)、醇碱比1:4、反应温度51℃、硫酸铵饱和度33%,在此条件下得到麦麸蛋白质的得率为5.23%,水不溶性膳食纤维提取率为88.76%,水溶性膳食纤维提取率为3.08%。该数学模型对优化麦麸蛋白和水不溶性膳食纤维的提取工艺可行。     

花生膳食纤维的提取研究

目的:花生除少部分作为干果食用之外,大部分作为油料资源用于榨取食用油脂,花生粕是花生仁提取油后的副产物,主要作为饲料和肥料,没有得到很好的开发与利用,本研究以花生粕为原料,提取功能性食品添加剂膳食纤维。方法:主要研究了NaOH浓度、提取温度和提取时间对花生粕水不溶性膳食纤维提取率的影响,并通过正交实验对膳食纤维制备工艺进行优化,同时研究了水溶性膳食纤维的提取条件。结果:水不溶性膳食纤维的提取工艺条件:15%NaOH溶液,40℃提取50min,提取率为34.20%;水溶性膳食纤维的提取工艺条件:提取水不溶性膳食纤维后的滤液调pH到3.0除去蛋白质,再调pH到6.5,乙醇沉淀,提取率为8.70%。结论:用化学分离法提取花生粕中膳食纤维是可行的,且可提高花生附加值,增加农民收入。     

超声波辅助提取花生壳水溶性膳食纤维工艺研究

以花生壳为原料,采用超声波辅助法提取水溶性膳食纤维,在单因素试验基础上,通过正交试验确定提取花生壳水溶性膳食纤维最优工艺。结果表明,提取花生壳水溶性膳食纤维最优工艺条件为:提取温度80℃、提取时间20 min、料液比1:15(g/mL)、超声波功率320 W;在此工艺条件下,花生壳水溶性膳食纤维提取率为18.54%;所得水溶性膳食纤维膨胀力为6.73 ml/g、持水力为7.21 g/g,成品呈黄褐色,气味良好。     

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.     

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.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.