用NaHSO3浸泡与α-淀粉酶水解提取薏苡仁蛋白工艺的研究

研究了用NaHSO3浸泡与α-淀粉酶水解提取薏苡仁蛋白的工艺,实验结果表明,在45℃下,用pH5.0浓度为0.4%的NaHSO3溶液浸泡薏苡仁粉15h时,薏苡仁蛋白的溶出效果最好。在此基础上,通过正交实验发现,用高温淀粉酶水解淀粉提取薏苡仁蛋白的最佳条件为:每克淀粉加200Uα-淀粉酶,在80℃下水解4h。在此条件下所得样品蛋白含量可达60.8%,淀粉残留为14.1%。     

玉米淀粉实验室提取方法研究

以普通黄马齿玉米为原料,采用湿法提取淀粉工艺,制得淀粉得率高、优质纯净玉米淀粉;通过大量实验设计筛选出最佳提取方案:浸泡温度50℃,乳酸和NaHSO3浓度均为0．5％,浸泡时间36 h,流槽倾斜度为0．015 cm／cm。     

生物酶–超声波协同提取制备米糠多糖工艺

以脱脂米糠为原料,采用淀粉酶和糖化酶水解除去淀粉,采用胃蛋白酶除去蛋白,在酸性条件和碱性条件下各提取一次,优化米糠多糖提取工艺。实验结果表明,脱脂米糠以1∶15 g/mL料液比加水充分混匀后,以3%的淀粉酶水解2 h、3%糖化酶水解1 h、3%胃蛋白酶水解1 h除去淀粉和蛋白,分别在酸性和碱性条件下70℃、200W超声提取90min,得到米糠多糖的得率为8.12%。冷冻干燥后的粗多糖含有84.2%的米糠多糖,6.6%的粗蛋白,2.1%的灰分和5.8%的水分。     

豌豆淀粉及蛋白生产的研究

通过对现有豌豆淀粉及蛋白生产提取工艺的考察研究,筛选出影响豌豆淀粉和蛋白的主要工序,确定最佳生产工艺和提取方法,即在常温下使用0、1％H2SO3溶液在浸泡罐内进行浸泡,浸泡时间为50～60h,获得比较理想的产品品质和收率。淀粉收率达到47．6％,蛋白含量小于0．6％;蛋白收率25．4％,蛋白粉蛋白含量90．25％。     

酶法提取麸皮中膳食纤维的研究

通过耐高温α-淀粉酶和蛋白酶对麸皮中的淀粉和蛋白质进行水解,提取麸皮中的膳食纤维。通过正交试验设计,确定α-淀粉酶去除麸皮淀粉的反应条件为：酶用量为3％（[E],[S]）,90℃,水解2h;选择水解蛋白质能力较强的碱性蛋白酶对麸皮进行水解以除去其中的蛋白质,碱性蛋白酶降解蛋白质的优化条件为：蛋白酶用量1．4％（[E],[S]）、60℃、水解1．5h。在上述优化工艺条件下,麸皮中膳食纤维的提取率达到77．6％。     

水酶法提取花生水解蛋白的研究

采用水酶法从冷榨花生饼中提取水解蛋白。以溶出的蛋白质浓度为指标,研究了提取花生蛋白的酶解工艺及条件。结果表明,先用碱性蛋白酶水解再用中性蛋白酶水解效果优于单一酶,碱性蛋白酶最适条件为：温度为55℃,pH值为9．0,加酶量为0．8％,水解时间为3h;中性蛋白酶最适条件为：温度为50℃,pH值为6．5,加酶量为0．3％,水解时间为1．5h。此条件下,蛋白提取率可达90．29％。     

水酶法提取花生水解蛋白的研究

采用水酶法从冷榨花生饼中提取水解蛋白。以溶出的蛋白质浓度为指标,研究了提取花生蛋白的酶解工艺及条件。结果表明,先用碱性蛋白酶水解再用中性蛋白酶水解效果优于单一酶,碱性蛋白酶最适条件为：温度为55℃,pH值为9．0,加酶量为0．8％,水解时间为3h;中性蛋白酶最适条件为：温度为50℃,pH值为6．5,加酶量为0．3％,水解时间为1．5h。此条件下,蛋白提取率可达90．29％。     

玉米醇溶蛋白提取及其对酒精发酵的影响

用磷酸盐缓冲液在40℃浸泡玉米36h后，进行脱胚芽处理，用胚乳提取醇溶蛋白。实验确定了提取玉米醇溶蛋白的最佳工艺条件为：添加液料比为6H，的75％乙醇溶液，在60℃浸提2h后，离心分离，醇溶蛋白回收率为67-37％。分别用浸泡过的整粒玉米和胚乳及未经浸泡的胚乳提取玉米醇溶蛋白，结果表明，浸泡有利于醇溶蛋白的提取。将提取醇溶蛋白后的玉米胚乳残渣进行酒精发酵，淀粉出酒率为53．40％，略高于对照试验的53．04％。     

甘薯叶可溶性蛋白提取工艺研究

以甘薯鲜叶为原料，研究了碱提酸沉法提取甘薯叶可溶性蛋白的工艺，通过单因素和正交实验，确定出提取甘薯叶可溶性蛋白的最佳工艺条件：提取液（0．05％NaHSO3）pH8．0，料液比（w／v）1：4，打浆时间3min，酸沉pH4．5。该优化条件下可以得到纯度为50％一65％的甘薯叶可溶性蛋白，可溶性蛋白提取率为14％-18％。     

豌豆酸奶加工工艺研究

以豌豆为原料,对豌豆制作酸豆奶的加工工艺进行了研究。通过对不同浸泡液和浸泡时间的选择,得出最佳浸泡条件为：采用0．5％的NaHCO3溶液,按干豆重3倍的量加入,常温浸泡16h;针对豌豆淀粉含量高,豆浆易分层的特点,加入α-淀粉酶对其进行酶解处理,以α-淀粉酶加入量、酶解温度和处理时间为因素,采用L9（3^4）正交试验,得出最佳酶解条件为：加入0．07％α-淀粉酶,在85℃水浴处理40min;最后对豌豆酸奶的发酵条件进行了研究,确定最佳发酵条件为：乳酸菌接种量5％,加糖量5％,发酵5．5h。     

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