芹菜花生酸奶的研制

以芹菜、花生和鲜牛奶为主要原料,经过保加利亚乳杆菌和嗜热链球菌发酵,通过单因素试验和正交试验,得出芹菜花生酸奶的最佳制作工艺条件为:芹菜汁添加量12％,花生浆添加量9％,蔗糖添加量7％,接种量3％,发酵温度42℃,发酵时间4h.     

芹菜汁酸豆奶的研制

探讨了芹菜汁酸豆奶的工艺,并采用正交试验确定芹菜汁酸豆奶的最佳发酵条件,结果为：保加利亚乳杆菌（Lactobacillus bulgaricus）嗜热链球菌（Streptococcus thermophilus）=1：1,接种量为4%,芹菜汁添加量为10%,脱脂乳粉的添加量10%,发酵温度40℃,发酵时间5h.     

发酵型酸豆乳工艺条件的研究

以大豆为主要原料,研究了嗜热链球菌、保加利亚乳杆菌和嗜酸乳杆菌为混合发酵剂进行乳酸菌发酵酸豆乳的制备工艺.通过单因素和正交实验确定了最佳制备工艺:接种嗜热链球菌、保加利亚乳杆菌、嗜酸乳杆菌的比例为1∶1∶2,接种量为4％,发酵温度为43℃,蔗糖的添加量为6％,发酵时间4h.在此条件下发酵的酸豆乳活菌数可达2.8×108 mL-1,具有淳厚的豆香味和清香的乳酸味,质地均匀,且酸甜可口.     

混料设计法应用于多菌种发酵制备大豆凝胶蛋白

采用保加利亚乳杆菌、嗜热链球菌、嗜酸乳杆菌及其混合菌对大豆分离蛋白进行发酵,应用流变仪和质构仪等手段进行分析,结果表明混合菌的发酵产酸性能和对大豆分离蛋白体系凝胶性质影响优于单一菌.在单因素试验的基础上,采用混料设计对混合菌发酵大豆分离蛋白制备凝胶的发酵条件和混合菌配比进行优化.最优发酵工艺条件为:大豆分离蛋白质量分数12％,葡萄糖添加量5％,40℃发酵4.8h,4℃冷藏12h.改变混合菌的配比可得到不同性能的大豆分离蛋白凝胶,当保加利亚乳杆菌添加量1.27％、嗜酸乳杆菌添加量0.37％时,可得到凝胶强度为145.98 g的高强度凝胶;当保加利亚乳杆菌添加量0.48％、嗜热链球菌添加量0.99％、嗜酸乳杆菌添加量0.14％,可得到持水率为87.28％的高持水率凝胶.     

凝固型降胆固醇全蛋发酵饮料加工工艺研究

目的：以鲜鸡蛋为主要原料，通过乳酸菌发酵作用加工凝固型降胆固醇发酵全蛋饮料；方法：对嗜热链球菌、保加利亚乳杆菌、嗜酸乳杆菌、两岐双岐杆菌及其复合菌种的降胆固醇能力进行测定，选择嗜热链球菌和保加利亚乳杆菌作为复合发酵菌种，对发酵基质配方和发酵条件进行优化；结果：确定全蛋液用量32％、葡萄糖用量1．25％、CMC—Na用量0．3％、卡拉胶用量0．2％、培养时间24h为优选条件，在优选条件下胆固醇降解率可达36．03％，且感官质量较好。     

芹菜营养保健酸奶的研制

以芹菜和新鲜牛乳为主要原料,以蔗糖、稳定剂等为辅料,以保加利亚乳杆菌和嗜热链球菌组成的混合发酵剂作为生产发酵剂,并加入芹菜汁,经杀菌、均质、接种、发酵等工艺,最后生产出来有芹菜香味的、并略带酸味的具有营养和保健功能的芹菜酸牛奶。     

天然竹笋酸奶的研制

以奶粉和竹笋为主要原料，用保加利亚乳杆菌和嗜热链球菌混合发酵制备，采用4因素3水平的正交试验研制出的天然竹笋酸奶的最佳生产工艺条件为：脱脂奶粉12％、原笋浆50％、蔗糖10％、接种量3％、发酵温度44℃、保加利亚乳杆菌和嗜热链球菌菌种比1：2、发酵时间4h、明胶0.3％。该产品口感柔和、风味独特，是一种集营养、保健于一身的新型乳品。     

菊芋对嗜热链球菌和保加利亚乳杆菌生长的影响研究

以菊芋粉为材料,嗜热链球菌和保加利亚乳杆菌为实验菌株,研究菊芋在牛乳中对2菌株生长的影响,结果表明,在牛乳中加入菊芋粉,凝乳时间均有所缩短,菊芋粉对保加利亚乳杆菌和嗜热链球菌的生长无抑制作用,0．6％菊芋粉添加量对保加利亚乳杆菌生长有显著促进作用。     

搅拌型荔枝发酵酸乳的研制

本文以荔枝为原料，添加适量奶粉，经乳酸菌发酵制成一种新型酸牛奶．将荔枝肉．砂糖和奶粉按照一定比例混合调配，杀菌后按嗜热链球菌和保加利亚乳杆菌1：1接种，接种量为2％，42℃恒温发酵4小时，冷却后搅拌灌装，即制得营养丰富，富有荔枝风味的液态酸奶。     

分段发酵提高酸乳中活菌总数的研究

为提高酸乳中乳酸菌活菌数量,在测定不同温度下嗜酸乳杆菌生长曲线及保加利亚乳杆菌与嗜热链球菌1∶1混菌发酵生长曲线的基础上,采用分段发酵的方式,发酵初期按1%接种量接入嗜酸乳杆菌,待发酵进行4h,嗜酸乳杆菌的数量达到107时,再接入保加利亚乳杆菌和嗜热链球菌,接种量均为1%。发酵结束后,测得最终活菌数可达109,相比3种菌一次性接种发酵,活菌数量提高了1个数量级。     

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.