酶法提取黑加仑籽油

对于酶法提取黑加仑籽油进行了初步探讨。经对比实验筛选出从黑加仑籽中提油的3种酶:复合纤维素酶、果胶酶和中性蛋白酶。通过正交实验分别对3种酶的酶解条件进行优化,得到的结果为,果胶酶:添加量0.5%,pH 6,酶解时间4 h,料液比1∶5,酶解温度50℃,在此条件下提油率为8.03%;复合纤维素酶:添加量1.5%,pH 6,酶解时间4 h,料液比1∶6,酶解温度55℃,在此条件下提油率为10.73%;中性蛋白酶:添加量1.0%,pH 8,酶解时间5 h,料液比1∶5,酶解温度45℃,在此条件下提油率为11.43%。将3种酶复合使用后提油率达到13.89%,显示复合酶法的提取效果要好于单一酶法。     

复合酶法提取菜籽油工艺优化

为提高菜籽油的得率,探讨应用复合酶法提取菜籽油的最佳工艺条件。以挤压处理后的油菜籽为原料,提油率为考察指标,对复合酶种类和配比进行筛选后,在单因素试验基础上,通过响应面优化试验得出最佳酶解条件。结果表明：以中性蛋白酶、果胶酶和α-淀粉酶为复合酶组成,其配比为0.573:0.315:0.112;酶解最佳工艺条件为：酶解温度50 ℃、酶解时间4 h、酶解pH 6、料液比1:4、复合酶添加量2%,在此条件下油菜籽清油的提油率可达92.333%。     

不同酶处理对小麦胚芽油提取率的影响

研究不同酶处理对小麦胚芽油提取率的影响,确定最佳水酶法提取小麦胚芽油工艺。选用纤维素酶、半纤维酶、酸性蛋白酶、淀粉酶、果胶酶作为提取酶,对小麦胚芽进行酶解,研究了不同酶处理对提油率的影响。单一酶处理试验中,分别用纤维素酶和酸性蛋白酶处理的提油率较高;复合酶处理试验中,酸性蛋白酶和纤维素酶组合处理的提油率最高;且复合酶处理比单一酶处理的提油率高。经过正交试验得出小麦胚芽油水酶法最优提取工艺为:复合酶(酸性蛋白酶∶纤维素酶=5∶1),酶解pH=5,酶解温度45℃。经验证试验小麦胚芽提油率可达到65.53%。试验提取的小麦胚芽油不饱和脂肪酸含量高达82%以上,营养品质较好。     

水酶法提取胡麻籽油工艺条件的研究

采用水酶法提取胡麻籽油并对其工艺条件进行了详细研究。在单因素实验的基础上,通过正交实验得出了最佳工艺条件,即20 g研碎油料,加酶量为0.10 g,酶解温度50℃,酶解时间1h,最适pH 5.4,料液比1∶10,浸提温度90℃,浸提时间9 h。另外,水酶法提取胡麻籽油的提油率比水浸法提取胡麻籽油的提油率高24.55%。     

猪血红蛋白的酶解工艺研究

目的 研究猪血红蛋白的酶解工艺.方法 用组合酶Ⅰ（蛋白酶F与蛋白酶P）和组合酶Ⅱ（蛋白酶F与蛋白酶N）同步酶解猪血红蛋白.结果 确定最佳工艺参数,组合酶Ⅰ的最佳酶解条件为：酶添加量0.2％,温度50℃,料水比1∶1.25,pH 7.5,水解时间20 h;组合酶Ⅱ的最佳酶解条件为：酶添加量0.24％,温度50℃,料水比1：1.75,pH 8.0,酶解时间20h.此工艺条件下,组合酶Ⅰ和组合酶Ⅱ三氯乙酸可溶性氮含量（TCA-SN指数）分别为71.72％和87.82％,两种组合酶的蛋白质回收率均达90％.结论 组合酶Ⅱ较适于工业生产.     

水酶法联产核桃油和核桃多肽工艺优化及油脂脂肪酸分析

为提高核桃的综合利用率,优化了水酶法联产核桃油和核桃多肽的工艺条件,并分析了油脂的脂肪酸组成。通过比较4种不同的蛋白酶与纤维素酶复配对核桃提油率和多肽产量的影响,确定最佳酶组合;在此基础上,通过单因素和L₁₈（35）正交试验研究了pH、酶解温度、酶解时间、料液比和加酶量对核桃提油率以及多肽产量的影响,得出最佳工艺条件;利用气相色谱技术分析了核桃油的脂肪酸组成。结果表明,木瓜蛋白酶与纤维素酶复配（2:1,w/w）为最佳酶组合;水酶法制备核桃油和核桃多肽的最佳联产工艺条件为:加酶量3.0%,料液比1:5（g/mL）,pH5,时间3.0 h,温度60 ℃;在此工艺条件下,核桃提油率可达53.37%,多肽产量为4.01 mg/g。气相色谱测定结果表明,核桃油中共检测出5种脂肪酸,分别为亚油酸（62.26%）、油酸（18.64%）、α-亚麻酸（10.57%）、棕榈酸（6.00%）、硬脂酸（2.53%）;核桃油以不饱和脂肪酸为主,其总含量高达91.47%,其中多不饱和脂肪酸含量为72.83%,单不饱和脂肪酸含量为18.64%。该工艺可为水酶法联产核桃油和核桃多肽的产业化应用提供参考。     

响应面优化水酶法提取鳄梨油工艺

以新鲜的鳄梨果肉为原料,采用水酶法提取鳄梨油,对酶源进行筛选,并在单因素实验的基础上,利用中心组合(Box-Behnken)实验设计原理,对3个主要影响因素(料水比、酶用量及酶解时间)进行响应面优化;同时与冷榨法、溶剂法提取的鳄梨油进行部分理化性质比较。结果表明,选用木瓜蛋白酶为酶源,最佳工艺条件为:料水比1:5、酶用量1.10%、酶解温度45℃、酶解时间4 h、pH6.0,提油率高达79.49%。水酶法所提取鳄梨油的品质总体上略高于溶剂法,与冷榨法持平。     

红薯膳食纤维物理-酶法的提取工艺研究

以红薯为原料,对物理-酶法提取膳食纤维的工艺进行研究。结果表明,物理筛分的前处理最佳工艺为浸泡料液比1∶4,浸泡时间8h,浸泡温度50℃;酶解工艺的最佳条件为酶解料液比1∶6,酶解时间1.5h,酶解温度50℃,酶解pH4.0,添加α-淀粉酶质量分数0.03%。在此条件下,原料淀粉去除率达到84.93%,得到的红薯膳食纤维中粗纤维含量达到82.33%。     

水相法提取牡丹籽油及破乳工艺的研究

采用水相法提取牡丹籽油,碱提形成稳定乳状液后,用酶和乙醇进行破乳。选择料液比、酶活添加量、酶解时间、酶解温度作为试验的四个因素,在单因素试验的基础上,进行四因素三水平的正交试验优化提油工艺。通过极差分析可看出,四个因素对牡丹籽出油的影响大小为:料液比酶活添加量酶解温度酶解时间。通过正交工艺优化,得出最佳的提油工艺为:料液比1︰6(g/m L)、酶活添加量600 U/g、酶解时间2.5 h、酶解温度60℃。在此优化条件下,牡丹籽出油率可达到17.13%。提油率为62.29%。     

超声波辅助水酶法提取胡麻油工艺条件的研究

以胡麻籽为原料,研究了超声波辅助水酶法提取胡麻油的工艺条件。研究结果表明:最佳复合酶为酸性蛋白酶和纤维素酶(2∶1),最佳酶解条件为加酶量0.20 g(20 g底物)、酶解pH值5.0、酶解温度50℃、酶解时间1 h,在此条件下提油率为75.1%;当在超声温度45℃、超声频率45 kHz下处理15 min提油率可升到81.1%。     

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