河蚬肉酶解液的活性炭脱腥脱苦条件优化

采用双酶解法制备河蚬肉酶解液,用活性炭进行脱腥脱苦吸附处理,测定蛋白质回收率,结合气味分析,评价吸附效果。通过正交实验获得较优吸附条件:起始pH值调为4,加入3%的粉末活性炭,55℃吸附30min,处理液的腥味苦味明显降低。     

鲍鱼内脏酶解液抗氧化能力及脱腥工艺研究

以鲍鱼内脏粗蛋白为原料,使用木瓜蛋白酶为工具酶对其进行高效酶解,以水解度和抗氧化能力为指标,通过正交试验优化酶解工艺,得到最佳酶解工艺:p H 9,酶/底物([E]/[S])1 000 U/g,酶解温度60℃,底物浓度5%,此时酶解液DPPH自由基清除率为(88.14±0.92)%,水解度为(14.12±0.53)%;以食品级活性炭粉末为吸附剂,以蛋白质损失率和感官评价为指标,得到酶解液的最佳脱腥工艺为:活性炭的质量分数1.0%,吸附时间为60 min,吸附温度为50℃,在该条件下试验得到的蛋白质回收率为(88.06±0.24)%,腥味值为2.00。制备得到的酶解液具有较强抗氧化能力,脱腥液无明显苦腥味,液体澄清呈淡黄色,感官品质有了很大改善。     

虾头水解蛋白脱苦脱腥方法的研究

为去除虾头水解蛋白溶液的苦腥味,比较了粉末活性炭吸附法、酵母发酵法和环状糊精包埋法的脱苦脱腥效果。结果表明,酵母发酵与β-环糊精包埋联合去除苦腥味的效果最佳。通过添加1.5%的β-环糊精,60℃包埋60min,然后添加1%的酵母,在40℃下恒温发酵60min,离心分离后沸水浴5min。处理后的虾头水解蛋白液无苦腥味,且具有浓郁的鲜虾风味。     

三角帆蚌取Hgriopsis cumingii肉酶解工艺的研究

探讨了Asl．398中性蛋白酶水解三角帆蚌肉的具体工艺条件。通过正交实验，确定其最佳水解条件为；温度50℃，酶用量2．8％，肉水比1：2，时间9h。综合考虑各方面的因素，在实际生产中可采用40—45℃，酶用量2．4％，肉水比1：2或1：1，时间8h对蚌肉进行酶解。水解液可用于生产功能性蛋白饮料及调味配料。     

蛋黄降压肽酶解液脱色工艺的优化

采用单因素和正交实验法,用粉末活性炭对含蛋黄降压肽的酶解液进行脱色处理,考察了活性炭用量、pH、脱色温度和吸附时间等因素对脱色率、肽损失率和溶液活性损失率的影响。结果表明,粉末活性炭用量3%,pH4.5,脱色温度40℃,吸附时间30min的条件下,蛋黄降压肽酶解液脱色效果明显,肽损失率(LP)可控制在20%以下,脱色率(DE)可达到86.3%,而酶解液对血管紧张素酶(ACE)的抑制率(IP)为77.89%,活性损失率为6.39%。      

蛋黄降压肽酶解液脱色工艺的优化

采用单因素和正交实验法,用粉末活性炭对含蛋黄降压肽的酶解液进行脱色处理,考察了活性炭用量、pH、脱色温度和吸附时间等因素对脱色率、肽损失率和溶液活性损失率的影响。结果表明,粉末活性炭用量3%,pH4.5,脱色温度40℃,吸附时间30min的条件下,蛋黄降压肽酶解液脱色效果明显,肽损失率(LP)可控制在20%以下,脱色率(DE)可达到86.3%,而酶解液对血管紧张素酶(ACE)的抑制率(IP)为77.89%,活性损失率为6.39%。     

波纹巴非蛤酶解蛋白脱腥技术研究

研究比较了NaCl盐析法、菊花茶掩蔽法、活性炭吸附法、β-环糊精包埋法4种方法对波纹巴非蛤酶解蛋白脱腥效果的影响。结果表明,活性炭吸附法脱腥效果最佳。进一步通过正交实验确定了活性炭对波纹巴非蛤酶解蛋白腥味脱除的最佳吸附条件:活性炭添加量为3.0%,作用温度为40℃,作用时间为35min,其脱腥值为2。      

胰蛋白酶对蚌肉蛋白水解条件的研究

采用胰蛋白酶对取珠后的褶纹冠蚌肉进行水解,通过正交实验L16(45)法确定了酶解条件。结果表明,酶解的最适条件为温度45℃,pH4.0,时间7h,加酶量2.2％,在该条件下蚌肉蛋白的水解度可达43.56％。     

牡蛎酶解过程的成分变化及脱腥初步研究

对牡蛎原浆液、酶解液及其浓缩液的基本营养成分进行分析比较,分别采用了活性炭吸附、β-环状糊精包埋法和酵母发酵法对牡蛎酶解液进行脱腥,研究了温度,时间,pH和脱腥剂用量等对脱腥效果的影响. 结果表明:牡蛎蛋白质、水分含量分别为9. 46%和81. 42%:酶解后,蛋白质和水分含量分别为7. 36%和83. 18%;酶解液浓缩后,蛋白质含量高达52. 55%. 活性炭脱腥效果最优:用量为0. 5%,在pH7. 0、30℃条件下吸附0. 5 h,酶解液基本无腥味,蛋白质回收率可达84. 65%. 促进牡蛎酶解液的推广应用.     

大豆降压肽脱色工艺的优化

以脱色率和肽损失率为评价指标,通过单因素和正交试验优化脱色工艺,研究活性炭对大豆降压肽酶解液的脱色条件。结果表明,粉末活性炭的脱色效果最佳,其最佳脱色条件为：pH5．0,活性炭用量0．75％,脱色时间60min,脱色温度45℃。在该优化条件下,酶解液的脱色率为91．03％,肽损失率为2．78％。     

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