响应面法优化茶奶酪发酵工艺研究

将茶叶提取物添加到奶酪中,在茶叶添加量、发酵剂添加量、发酵温度、发酵时间和凝乳酶添加量的单因素试验基础上,通过响应面分析方法优化茶奶酪生产工艺,确定最佳工艺参数为:茶叶添加量1%、发酵剂添加量0.3%、发酵温度40℃、发酵时间7h和凝乳酶添加量2mg/L,此条件下的茶奶酪色泽美观、香味浓郁,口感优良,水分含量为29.20%,感官评分为94.78分。     

蛹虫草茶酒的研究

将茶叶加水浸提制得茶汁,将蛹虫草培养基进行糊化、液化和糖化后加入一定比例的茶汁和白砂糖,以活性黄酒干酵母为发酵剂,采用液态发酵法酿造出具有保健功能的茶酒,试验结果表明,茶酒发酵的最佳条件为:蛹虫草培养基水解液和茶汁的比例为1∶1,发酵温度30℃,发酵时间9d、酵母量0.2％、糖度16％、pH值为4.5,该茶酒酒精度为9.7％vo1,兼有茶和酒的香气,有一定的保健功能.     

嗜杀酵母Sa2发酵籼米小曲酒的工艺研究

该文对以籼米为原料,纯种根霉曲作糖化剂,嗜杀酵母(Sa2)曲作发酵剂的小曲酒的生产工艺进行了探讨,并对影响小曲酒的出酒率和品质的因素(糖化温度、糖化时间、纯种根霉曲添加量、嗜杀酵母曲添加量、加水量和发酵时间)作了研究.确定了籼米小曲酒发酵的最佳工艺条件:纯种根霉曲加曲量0.4％,糖化温度30℃,糖化时间1d,加水量120％,发酵时间4d,嗜杀酵母曲种加曲量0.8％.     

发酵型草莓蜂蜜酒的工艺优化研究

以草莓为主要原料,用蜂蜜调整糖度,通过单因素实验与正交实验对复合酶法提取草莓汁的工艺条件和草莓蜂蜜酒的发酵工艺进行优化研究.结果表明,草莓的最佳酶解工艺条件为:复合酶添加量0.2％(果胶酶与纤维素酶添加量比例为1∶4),酶解温度50℃,pH4.5,酶解时间4.0h,草莓出汁率可达90.2％.草莓蜂蜜酒的发酵工艺条件为:发酵初始糖度16％,酵母菌直投用量0.4％,发酵温度30℃,发酵时间4d,酒精度可达8.4％vol.     

酸浆果酒酿造工艺研究

以酸浆为原料了生产酸浆果酒工艺,考察果胶酶用量对酸浆出汁率的影响,以及SO2添加量、发酵温度、接种量对酸浆果酒品质的影响。结果表明：果胶酶用量为0．6g／kg时,可提高出汁率9％;酸浆酒的最佳发酵条件为：SO2添加量0．8mL／L-1．0mL／L,发酵温度为18℃～22℃,接种量5％。酿制出的酸浆果酒色泽好,澄清透明,酒味浓郁,酒体丰满,具有酸浆的特殊清香。     

山楂保健果酒的研制

研究以山楂为原料,分析了各种发酵条件对发酵过程的影响,通过单因素和正交试验,得出山楂果酒的发酵优化条件:山楂果酒的发酵温度26℃,酵母接种量0.10％,最适pH值为3.2.山楂榨汁时果胶酶最佳添加量为0.09％,可使出汁率达87％.该实验为山楂果酒新产品开发提供参考.     

不同茶类酸奶的研制

目的研制茶味酸奶,增加酸奶产品的多样性。方法采用6大茶类为原料,利用响应面优化方法确定茶叶酸奶的最佳配方。结果普洱茶、红茶、白茶、黄茶、绿茶、乌龙茶制作的茶叶酸奶最佳配方为:浸提茶汤茶水比为1:10,浸提温度为90℃,浸提时长为20min;牛奶中茶汤添加量5%,白砂糖添加量8%,菌种接种量2%,发酵时间6 h,发酵温度为42℃时制作的茶叶酸奶品质具佳。结论鲜牛奶中添加5%茶汤,在42℃下发酵6 h制作的茶叶酸奶奶香浓郁,与牛奶融合较好,具有独特口感与茶香,比普通酸奶滋味醇厚。     

红茶酒酵母驯化筛选及发酵工艺研究

以优质红茶叶为原料,通过不同浓度配比的茶汁YPD培养基对茶酒发酵酵母进行梯度驯化,筛选出1株对茶汁适应能力和发酵力都比较强的酵母Z-4。该酵母在含12％蔗糖茶汁培养基中发酵所得酒精度为10％vol,残糖量为7．5°Bx。并对温度、发酵液配比、pH值以及酵母接种量等发酵条件进行单因素分析,研究表明,最优发酵条件为：发酵温度25℃,茶与清水比1：60（g／v）,发酵液pH4,蔗糖含量12％,酵母接种量为3％,发酵时间7d。     

家庭自制酒酿的最佳条件

家庭自制酒酿的过程中,糯米的温度、酵母菌发酵的环境中水分含量、酒曲的量、温度以及发酵时间都对酒酿的制作产生影响.以优质糯米为主要原料,经传统工艺发酵制作酒酿,将糯米摊凉至35℃左右并加少量凉开水,酒曲添加量为2.4％(每250 g糯米添加6 g酒曲),发酵温度28℃,发酵72 h,此时出酒率高,品质好.     

安琪牌葡萄酒活性干酵母在草莓酒酿造中的应用

研究了安琪葡萄酒活性干酵母在草莓汁中的发酵条件。表明发酵温度为20℃,初始pH值为3．3,接种量为0．2％.SO2添加量为100mg／L,果胶酶量添加量为0．3g／L,发酵出的酒质较好。采用安琪葡萄酒活性干酵母酿制得干型草莓酒具有典型的草莓香和酒香。     

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.     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the