花生麸水不溶性膳食纤维的提取及其吸附亚硝酸根离子的研究

采用化学法从花生麸中提取了水不溶性膳食纤维,并用它对亚硝酸根离子进行了初步吸附实验,结果显示,花生麸水不溶性膳食纤维对亚硝酸根离子有较强的吸附能力,其最大吸附浓度Cmax高达31．12μmol／g。     

燕麦渣中的不溶性膳食纤维对NO2-吸附作用研究

从燕麦麸废渣原料中提取水不溶性膳食纤维,并用它对亚硝酸根离子进行了初步吸附实验,结果显示,燕麦渣水不溶性膳食纤维对亚硝酸根离子有较强的吸附能力。     

四种玉米皮膳食纤维的组分对其吸附等功能性质影响的研究

研究玉米皮膳食纤维的组分不同对其功能性质的影响。采用四种(水不溶性、水溶性、水溶性与水不溶性比例为1∶3和含游离阿魏酸)玉米皮膳食纤维(分别记作A、B、C、D)在中性条件(pH 7,模拟小肠环境)和酸性条件(pH 2,模拟胃环境)下对吸附胆固醇、亚硝酸根离子、清除羟自由基等效果进行试验研究。结果对胆固醇的吸附中性条件优于酸性条件的效果,且C>D>B>A;对亚硝酸根离子的吸附,酸性条件优于中性条件,且A>C>D>B;对清除羟自由基,D>C>B>A。得到结论为,四种玉米皮膳食纤维均可吸附胆固醇、亚硝酸根离子和清除.OH,且受膳食纤维的组分及酸碱环境影响。     

酱油渣不溶性膳食纤维的制备及其功能特性研究

以酱油渣为原料,采用酶法辅助碱法制各不溶性膳食纤维,并测定不溶性膳食纤维的膨胀性、持水力、抗脂质过氧化以及吸附亚硝酸根离子等功能特性.实验结果表明,不溶性膳食纤维制备的最佳工艺参数为:NaOH浓度为4%,碱解温度为50℃,碱解时间为70min,酱油渣不溶性膳食纤维得率达37.89%.酱油渣不溶性膳食纤维具有良好的膨胀性、持水力、抗脂质过氧化和吸附亚硝酸根离子的作用,在胃液pH值条件下,在120min时不溶性膳食纤维吸附性能趋于饱和,吸附率达到72.6%,根据模拟方程求得在48.8min吸附率达到50%.     

蔓越莓中膳食纤维的结构性质和功能性质研究

目的 考察蔓越莓中膳食纤维的结构性质和功能性质。方法 利用酶解法提取蔓越莓总膳食纤维、不溶性膳食纤维和可溶性膳食纤维, 并采用红外光谱和高效液相色谱测定其官能团结构和分子量, 采用质构仪和粘度计测定其凝胶性质和粘度, 同时对膳食纤维吸附亚硝酸根离子、交换阳离子、胆固醇、重金属和葡萄糖的能力进行研究。结果 总膳食纤维和不溶性膳食纤维的提取率较高, 分别为54.67%和38.70%, 膳食纤维具有凝胶和粘度的性质, 同时在功能上有吸附亚硝酸根离子, 交换阳离子, 吸收胆固醇, 重金属离子和葡萄糖的性能。结论 蔓越莓膳食纤维具有特殊的结构性质和很好的功能活性, 可以开发蔓越莓新功能食品。     

玉米皮膳食纤维性质的研究

以玉米皮为原料,分别制备A(玉米皮水不溶性膳食纤维)和B(混合玉米皮膳食纤维)。通过对比A和B的持水力、膨胀力、吸油力以及对胆固醇、亚硝酸根离子的吸附能力这些指标来研究玉米皮膳食纤维的性质。试验结果表明:B的性能优于A。B的持水力和吸油力比A分别高出20.21%和9.87%;A的膨胀力比B高出4.14%;随着pH值的不断增大,膳食纤维对胆固醇的吸附能力增强,在pH7时B对胆固醇的吸附能力比A提高了约33.33%;溶液中残余亚硝酸根离子的浓度随着时间延长而呈下降趋势,并且pH值对样品吸附亚硝酸根离子的能力有较大的影响,在60 min时A和B在pH2时吸附亚硝酸根离子的浓度均比在pH7时高出46.72μmol/L。     

浒苔不溶性膳食纤维理化性质研究

研究了浒苔不溶性膳食纤维的理化性质。研究结果表明：浒苔膳食纤维的持水力为12.22g/g,膨胀力为6.40mL/g,吸附饱和脂肪的能力为11.20g/g,吸附不饱和脂肪的能力为8.65g/g,pH值7条件下基本不吸附亚硝酸根离子,pH值2条件下吸附亚硝酸根离子的能力逐渐增大,90min时为6.44mmol/g。以上研究表明浒苔膳食纤维具有较好的理化性质。     

超声波辅助浸提小麦膳食纤维及其理化性质研究

采用超声波辅助浸提法制备小麦麸皮可溶性物质和不溶性膳食纤维,并研究了不同干燥方式对不溶性膳食纤维理化性质的影响。在膨胀力方面,经过低温真空干燥的膳食纤维大于经过真空冷冻干燥的;在吸附脂肪方面,经过低温真空干燥的膳食纤维小于经过真空冷冻干燥的,而且小麦膳食纤维吸附饱和脂肪的能力明显强于吸附不饱和脂肪的能力。在吸附亚硝酸根方面,受体系的pH值影响较大,在pH值为7时,小麦膳食纤维基本不吸附亚硝酸根;而在pH值为2时,溶液中残留的亚硝酸根的含量随时间呈现明显减小的趋势,低温真空干燥处理的吸附亚硝酸盐的能力强于冷冻真空干燥所制备的膳食纤维。     

小米麸皮酶法改性工艺及其功能特性

采用纤维素酶对小米麸皮膳食纤维进行改性处理，以可溶性膳食纤维（soluble dietary fiber，SDF）得率为指标，通过单因素试验及正交试验优化改性条件，并对处理前后小米麸皮膳食纤维的持水力、持油力、膨胀力及体外胆固醇吸附能力、亚硝酸根离子清除率进行分析。结果表明：在纤维素酶添加量4.5%、反应时间9 h、反应温度60 ℃的条件下，可溶性膳食纤维得率最高，为24.77%；改性后小米麸皮膳食纤维（cellulase modified -millet bran total dietary fiber，CM-MBTDF）持油力显著上升，在25、37 ℃分别为2.750、3.440 g/g，是小米麸皮膳食纤维（millet bran total dietary fiber，MBTDF）持油力的2.3 倍和2.9 倍，持水力和膨胀力显著下降。此外，体外清除胆固醇能力显著升高，在pH2.0、pH7.0 时体外胆固醇吸附量分别为23.68、22.28 μmol/L，是MBTDF 体外胆固醇吸附量的1.31、1.96 倍。在pH2.0 时MBTDF、CM-MBTDF 均表现出较高的亚硝酸根离子清除率，其中CM-MBTDF 能够加快亚硝酸根离子清除速度，在pH7.0 时CM-MBTDF 亚硝酸根离子清除率显著提高。     

葡萄籽水不溶性膳食纤维对胆固醇吸附的特性

以葡萄籽水不溶性膳食纤维为试验材料,以胆固醇的吸附量为指标,通过对胆固醇浓度、水不溶性膳食纤维添加量、时间、温度对胆固醇吸附效果影响的研究,旨在确定葡萄籽水不溶性膳食纤维对胆固醇的吸附特性和吸附作用机理。经测定,葡萄籽水不溶性膳食纤维具有较好的持水性(0.440 g/g)和溶胀性(2.367 mL/g)。正交试验得出,其最佳吸附条件为胆固醇浓度4.0 mg/mL、葡萄籽水不溶性膳食纤维添加量0.05 g、吸附时间90 min、吸附温度40℃,葡萄籽水不溶性膳食纤维对胆固醇的吸附量为44.634 mg/g。经正交优化,其吸附量提高了2.25倍。经研究,葡萄籽水不溶性膳食纤维对胆固醇的吸附主要包括物理吸附和化学吸附。     

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.