瓶装黄酒杀菌条件与风味关系研究

对瓶装黄酒杀菌条件如杀菌温度、时间等对酒质、风味的影响作了系统的研究和分析，实验表明，杀菌温度在60—65℃之间，黄酒风味随杀菌时间延长得到改善。当杀菌温度超过70℃，杀菌时间控制在1h以内；当75℃杀菌，超过30min，黄酒风味有下降的趋势；80℃以上，黄酒风味随杀菌时间延长而变劣。(孙悟)     

瓶装黄酒杀菌条件与风味关系研究

本文主要对瓶装黄酒杀菌条件如杀菌温度、时间等对酒质、风味的影响作了系统的研究和分析，实验表明：杀菌温度在60℃-65℃之间，黄酒风味随杀菌时间延长酒质得到改善。当杀菌温度超过70℃，杀菌时间控制在1h以内，当75℃杀菌，超过30min，黄酒风味有下降的趋势。80℃以上，黄酒风味随杀菌时间延长而变劣。     

黄芪黄酒工艺初探

为增加黄酒的种类,以传统保健养生理论为基础,根据我国传统配方,结合现代科学理念,以黄芪、糯米为主要原料,以黄酒传统酿造工艺生产黄芪黄酒,重点研究酒曲种类、料水比、杀菌温度、杀菌时间、黄芪用量等几个因素对黄芪黄酒成品酒质的影响。结果表明最佳发酵工艺条件为雅大黄酒曲添加量为0.5%;料水比为1∶1.5;杀菌温度为80℃,可得到具有独特的风味和保健养生功能的黄芪黄酒。     

葛根清爽型黄酒的开发研究

以粳米,糯米,葛根为主要原料,采用传统黄酒酿造工艺和结合酿酒新技术生产葛根保健营养清爽型黄酒。探讨了原辅料的特性、原料配比、糖化发酵剂、发酵温度、时间、工艺技术和产品风味对酒质的影响,结果表明:粳、糯米、葛根的配比为1:1:0,5,并在酿造中以粳米制淋饭酒母,糯米蒸煮放凉喂饭,葛根加工酶解制浆喂加,主酵温度30℃～32℃,时间2d,然后在16℃～18℃后发酵45d,经压榨、过滤、杀菌、贮存、勾兑而成的葛根保健清爽黄酒,风味独特,并具有一定的养生保健功能。     

加热方法提高低度瓶装黄酒稳定性的研究

对用加热方法提高低度瓶装黄酒的稳定性进行了研究。研究结果表明．低度黄酒装瓶后。经９０℃,７ｍｉｎ加热处理,室温下静置１周,沉淀分离,再经巴氏杀菌处理,可保证黄酒稳定性,且对酒质风味无任何不良影响。     

热处理对牛骨酶解液美拉德反应产物呈味物质及挥发性成分的影响

探讨不同热处理条件(温度110,115,120,125,130 ℃和时间25,40,55,70,85 min)对牛骨酶解液美拉德反应产物(EBBH-MRP)呈味特性及挥发性风味成分的影响。结果表明:热处理温度低于130 ℃时,总游离氨基酸含量降低,这与鲜味氨基酸和苦味氨基酸变化趋势一致。风味核苷酸含量随温度上升呈增加趋势。在不同温度下,共检测到63种挥发性风味物质,包括醛类、酮类、醇类、酸类和杂环类化合物。当热处理时间超过40 min时,总游离氨基酸含量不断增加,风味核苷酸含量也缓慢增加。随着热处理时间的延长,挥发性风味物质种类减少,共检测到54种。醛类、酮类含量随时间的延长而明显增加,至70 min,其含量保持相对稳定。结论:适当的热处理条件可以提升EBBH-MRP的呈味及风味特性。     

自动化酿造黄酒系统发酵过程理化动态变化研究

通过对自动化酿造黄酒系统发酵过程理化和部分微量成份的动态测定研究,不同后发酵温度和后发酵时间对酒质影响试验研究,结果表明:自动化酿造黄酒系统发酵正常,酿制而成的成品黄酒各项指标和风味成份达到绍兴酒国家标准,发酵时间30天左右,则后发酵温度14℃左右为最佳,优化了发酵工艺参数;自动化酿造黄酒是可行。同时介绍了自动化酿造黄酒控制系统和工艺流程及自动化熟麦曲制作工艺流程。     

速冻机在黄酒过滤中的应用

速冻机采用双级制冷逐级降温冷却工艺对黄酒进行冷冻处理，按进口酒温25℃，第一级出口酒温8℃，第二级出口酒温-5℃进行配置。运行结果表明，各项指标符合设备设定参数和设计要求；制冷速度快、节能效果明显、安全适用；黄酒冷冻后再进行硅藻土过滤，过滤效果好；可明显减少沉淀析出量和减缓沉淀的析出时问，延长保质期，提高酒质。（孙悟）     

瓶装酒杀菌后快速冷却法改善黄酒风味的研究

本文研究了在室温25℃的情况下，瓶装黄酒杀菌后采用放置室内自然冷却，采用23℃的自来水冷却，采用0℃冰水混合物快速冷却，放置于35℃的温水中在室温下慢速冷却，放置过夜，第2天中午进行品评酒的风味。比较采用不同冷却方法制得的酒的风味差别，进行打分排序。结果发现采用快速冷却的黄酒风味明显优于自然冷却和慢速冷却的黄酒。夏季生产的瓶装黄酒在杀菌后，采用冷水冲淋，快速冷却改善黄酒风味的方法简便可行，而且效果显著，有一定推广应用价值。     

超高温瞬时杀菌对苏派黄酒风味物质的影响

为探究超高温瞬时杀菌对黄酒中风味物质的影响,该研究以苏派黄酒(江苏地区黄酒)为研究对象,考察不同条件的超高温瞬时杀菌处理后黄酒中挥发性风味化合物以及非挥发性风味物质含量的变化情况。结果表明,(1)超高温瞬时杀菌处理后,2种黄酒的挥发性风味化合物含量均显著降低(P<0.05),在135℃5 s处理条件下,甜黄酒挥发性风味化合物总量降低了17.5%;半干黄酒挥发性风味化合物总量降低了49.4%;(2)甜黄酒的有机酸总量较对照组有所增加,其中135℃5 s处理后有机酸总量显著性增加(相比对照增加了101.5%)(P<0.05);半干黄酒分别在120、130、135℃处理5 s后,有机酸总量均出现增加,其中120℃处理后显著性增加(相比对照组增加了39.9%)(P<0.05);(3)甜黄酒中17种游离氨基酸的含量无显著变化(P>0.05);而半干黄酒的氨基酸总量显著性下降(P<0.05),其中在125℃5 s处理条件下,氨基酸含量下降幅度最大(相比对照组降低了17.6%)。说明超高温瞬时杀菌对苏派黄酒中的风味物质均有不同程度的影响,从而会改变黄酒中的原有风味。     

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

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.     

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.     

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.