糯米玉米酒酿发酵工艺及其清除DPPH自由基的能力

以糯米、玉米为主要原料,通过接种酒曲进行混合酒酿发酵,选取糯米和玉米配比、酒药添加量、发酵时间、发酵温度为主要因素,采用正交试验对混合酒酿的发酵工艺进行优化。结果表明,最佳发酵条件为糯米与玉米配比为1∶3,酒曲添加量为1.0%,发酵温度38℃,发酵28h。此甜酒具有较强的清除DPPH自由基的能力,其IC50为10.07μL。     

六粮风味米酒工艺研究

以玉米、大米、小米、黑米、糯米、糯玉米6种米为原料,以米根霉和酿酒活性干酵母为糖化发酵剂,通过单因素试验对6种淀粉质原料米酒酿造用麸曲和酒曲的种类、比例及接种量、发酵温度、发酵时间等进行研究,再采用正交试验优选出六粮风味米酒发酵的最佳工艺参数。结果表明:麸曲与酒曲最佳质量比为1∶1,加曲量为0.6%,30℃条件下发酵48 h;玉米∶大米∶小米∶黑米∶糯米∶糯玉米的质量比为1∶1∶1∶2∶2∶2。此时的米酒质量最佳,酒质地均匀、酒醪清澈、醇香浓郁,柔和爽口,具有独特的甜米酒风味。     

酸汤子发酵工艺的优化及其品质分析

目的 优化酸汤子的发酵工艺，比较传统发酵和人工接种发酵酸汤子的品质差异。方法 以有机玉米面粉为主要原料，以从传统发酵的酸汤子中分离纯化的植物乳杆菌和酿酒酵母按1:2 (V:V)进行酸汤子人工接种发酵，以感官评价为指标，通过单因素和响应面试验优化，研究了液料比、pH、发酵时间和发酵温度对酸汤子品质的影响。结果 实验结果表明，获得适宜的酸汤子发酵工艺为：液料比2:1，pH 6.9，发酵温度37℃，发酵时间16 h, 感官综合评价得分为92.9分。在缩短发酵时间的同时，与市售菌剂发酵的酸汤子、传统发酵的酸汤子相比，总酸含量分别提高了1.65倍、2.63倍；熟断条率分别降低2.65%、5.37%。结论 在最优条件下制作的酸汤子味香而酸甜，顺滑爽口。与传统发酵相比，采用人工接种的酸汤子在外观品质、适口性及营养方面均得到很大提升，本研究为酸汤子工业化生产提供实验参考数据。     

芦荟糯米保健醋的研制

以芦荟原汁、糯米、酿酒干酵母、醋酸菌为原料,通过单因素实验和正交试验,探索了芦荟糯米醋的发酵工艺。通过正交试验确定了最佳组合为酵母活化液接种量为1.0%(V/V)、糯米与芦荟汁混合比为3∶2(g/mL),加水量为芦荟糯米混合量的1.5倍,发酵温度为28℃。芦荟糯米醋的最佳醋酸发酵条件为发酵温度30℃、酒精度10%(V/V)、接种量4%(V/V)、发酵时间96 h,可获得6.48 g/100 mL芦荟糯米保健醋。酿制的芦荟糯米醋香味独特,品位纯正。     

糯米-黑米混合甜酒发酵工艺研究

以糯米、黑米为主要原料,通过接种酒曲进行混合甜酒发酵,选取黑米和糯米的比例、酒曲添加量、发酵时间、发酵温度,采用单因素试验和正交试验对混合甜酒的发酵工艺进行优化。结果表明,最佳发酵条件为黑米与糯米的比例1∶5,酒曲添加量0.8%,发酵温度25℃,发酵时间32 h,此条件下所得的产品口感细腻醇甜,色泽晶莹,黑亮,酒香柔和。     

薯莨保健酒的研制

以糯米和薯莨为原料生产薯莨保健酒,通过单因素试验选取原料配比、料液比、酵母添加量、发酵温度为主要因素,采用Box-Benhnken响应面分析法对选取的主要因素进行回归分析,确定了发酵产薯莨保健酒的最优工艺条件为:A(原料配比)薯莨:糯米为1:0.3,B(酵母接种量)为0.4%,C(料液比)为1:0.6,D(发酵温度)为30℃。     

葛根糯米混合甜酒酿发酵工艺研究

以荆门地区葛根、糯米为原料,接种甜酒曲进行混合甜酒酿发酵。选取葛根与糯米的比例、酒曲接种量、发酵温度、发酵时间为条件,采用单因素试验和正交试验对混合甜酒酿的发酵工艺进行优化。结果表明,最佳发酵工艺为葛根与糯米质量比为1.0∶1.5、酒曲接种量为2.0%、发酵温度为30 ℃,发酵时间为3 d,在此条件下,制得的甜酒酿感官评分为85分,总糖含量为35.4%,酒精度为3.3%vol,黄酮含量为4.2 mg/100 mL,总酸含量为82.3 mg/100 mL（以柠檬酸计）。     

干酪乳杆菌发酵番茄酸汤的工艺优化

本试验探究应用干酪乳杆菌H1作为发酵剂接种西红柿优化制作酸汤发酵工艺。研究发酵温度、发酵时间、接种量和加盐量四个因素对番茄酸汤的品质的影响并对其发酵条件进行优化。在单因素实验的基础上,进行四因素三水平的响应面实验设计,基于模糊数学法得到的感官评定和总酸两个响应值,对人工接种干酪乳杆菌的番茄酸汤的发酵工艺进行优化,以确定其最佳发酵工艺。结果表明:在发酵温度25℃、发酵时间5 d,接种量2%,加盐量1.45%时,得到的番茄酸汤总酸达到1.23%,感官评分8.48±0.58,与理论值差异均不显著(p0.05),说明响应面的实验值和回归方程预测值基本吻合,响应面法建立的模型所确定的番茄酸汤的发酵条件稳定可靠,能为番茄酸汤工业化生产提供理论依据。     

基于GC-IMS技术对多菌系复合发酵特色米酸汤的风味特征研究

苗族传统米酸汤是以糯米或籼米为基质经自然发酵而成。为丰富米酸汤产品,明确多菌系复合发酵对米酸汤发酵生产的实际应用价值及米酸汤风味特征。本文以传统自然发酵的米酸汤(A)为对照、采用多菌系复合发酵不同基质米酸汤(红米酸汤-B、紫米酸汤-C、糯米酸汤-D、白米酸汤-E)为研究对象,利用气相色谱-离子迁移谱(Gas chromatography-ion mobility spectroscopy,GC-IMS)技术分析不同基质发酵米酸汤差异特征风味物质。结果表明:与传统自然发酵的米酸汤相比,糯米酸汤含有相对含量较高的乙酸乙酯,红米酸汤、紫米酸汤含有相对含量较高的乙酸丙酯,且经多菌系复合发酵后的红米酸汤、糯米酸汤、白米酸汤中贡献较大的主体风味物质种类皆比传统自然发酵的米酸汤丰富。采用正交偏最小二乘判别分析筛选出18种特征标志物(VIP>1)(Variable Importance for the Projection,VIP),通过热图聚类区分不同米酸汤样品的特征挥发性风味化合物,其中传统自然发酵的米酸汤以丁酸丙酯、丁酸丁酯、2-甲基丙酸乙酯等为特征风味物质,具有独特的菠萝果香味;红米酸汤以罗勒烯、柠檬烯-M、丙酸、乙酸丙酯等为特征风味物质,具有独特的柠檬与丁香香味;紫米酸汤以乙酸异丙酯、乙酸异丁酯、3-甲基丁醛、乙酸丙酯等为特征风味物质,具有独特的苹果样果香味;糯米酸汤以乙醇、乙酸乙酯等为特征风味物质,具有独特的米酒型香味;白米酸汤无特征标志物,但酸类物质较多,具独特的酸感。研究结果表明利用多菌系复合发酵米酸汤,具有改善并丰富米酸汤风味品质的显著优势,通过本实验还确定了不同基质发酵米酸汤的特征风味物质,为丰富米酸汤产品提供科学支撑。     

玉米甜酒的发酵特征与米酒酸奶生产工艺优化

用优化的甜酒曲发酵工艺参数对玉米糁进行发酵,发酵产物具有米酒风味特征,总酸度(49°T)和还原糖含量(50.88%)低于糯米发酵产物。用玉米糁和糯米(4∶6或6∶4)混合原料制备的发酵产物,其风味特征、酸度(70°T～72°T)和还原糖含量(56.61%～63.33%)与糯米发酵产物相似。乳酸菌在米酒发酵过程中没有显著的发酵产酸活性,而甜酒曲在酸奶发酵过程中有发酵活性。制备米酒风味酸奶简单可行的工艺是将玉米甜酒汁液添加到酸奶生产原料中,用正交试验设计法获得的最佳生产工艺条件为:米酒汁添加量15%,蔗糖添加量5%,培养温度42℃,培养时间为5h。     

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.