共查询到20条相似文献,搜索用时 109 毫秒
1.
以复合蛋白酶、木瓜蛋白酶、胰蛋白酶、风味蛋白酶分别酶解牛肉,得到牛肉酶解液,将4种牛肉酶解液分别和大曲混合后兑盐水发酵,比较不同蛋白酶制剂对发酵牛肉酱风味物质的影响。结果表明,添加复合蛋白酶组的总酸、氨基酸态氮和总氮含量分别为1.67 g/100 g、1.11 g/100 g和1.53 g/100 g,优于其他3种酶制剂组。添加复合蛋白酶和风味蛋白酶组的牛肉酱基质检出有机酸7种,提高了丙酸、酒石酸、苹果酸和琥珀酸的含量。在风味物质种类及含量方面,添加复合蛋白酶组检出67种,在酯类、醇类及酸类的种类和含量上比添加其他酶制剂组略有优势。 相似文献
2.
3.
羊骨汤不同酶解方式对其成分的影响 总被引:1,自引:1,他引:1
将羊骨以1:1的骨水比于0.05MPa高压2.0h后,再以不同的酶、酶浓度和酶解时间酶解骨汤,分析水解度(DH)、肽链长度(PCL)及游离钙含量的变化,并各筛选最优方案。结果表明:①游离钙含量最高:中性蛋白酶,酶浓度1500U/L,酶解6h;②DH最高:胰蛋白酶,酶浓度1:100,酶解6h;③PCL值最低:胰蛋白酶,酶浓度1:125,酶解6h;PCL值最高:碱性蛋白酶,酶浓度1500U/L,酶解8h。 相似文献
4.
以鳕鱼骨为原料制备酶解液,研究发酵时间、发酵温度、加盐量对酶解液氨基酸态氮含量和感官品质的影响。利用电子鼻结合顶空固相微萃取(HS-SPME)和气相色谱-质谱联用仪(GC-MS)分析酶解液发酵前、后挥发性风味物质。结果表明,酶解液的最佳发酵温度为35℃、发酵时间12 h、加盐量15%。在此发酵条件下,酶解液的氨基酸态氮含量为0.2685 g/100 mL,氨基酸总量为6177.28 mg/100 g,其中鲜味氨基酸谷氨酸和天冬氨酸含量较高。通过电子鼻主成分分析(PCA)可以很好地区分发酵前、后酶解液的风味。用SPME/GC-MS检测发酵后酶解液中香气活性化合物明显增加,从发酵液中共检测到18种香气活性化合物,其中醇类6种、醛类4种、吡嗪类3种、酮类2种、呋喃类2种、酚类1种。 相似文献
5.
6.
7.
8.
目的:分别选用胰蛋白酶、木瓜蛋白酶和Alcalase碱性蛋白酶水解兔骨粉,研究兔骨酶解液对小鼠脾淋巴细胞的增殖作用。方法:通过正交实验用MTT法检测酶解液对小鼠脾淋巴细胞的增殖作用以筛选得到最佳的酶解条件。结果:胰蛋白酶酶解最佳条件为时间5h、pH8.5、酶与底物比6000U/g、温度50℃、底物蛋白浓度6%;木瓜蛋白酶酶解最佳条件为时间4h、pH5.5、酶与底物比7000U/g、温度65℃、底物蛋白浓度6%;Alcalase碱性蛋白酶酶解最佳条件为时间5h、pH9、酶与底物比6000U/g、温度50℃、底物蛋白浓度6%。其中,木瓜蛋白酶酶解兔骨制得的酶解液对小鼠脾淋巴细胞增殖作用最强,其增殖率为95.70%,胰蛋白酶、Alcalase碱性蛋白酶对小鼠脾淋巴细胞增殖率分别为88.49%、69.22%。结论:三种不同蛋白酶酶解兔骨,其酶解产物对小鼠脾淋巴细胞都有增殖作用。 相似文献
9.
10.
甲鱼生物饮料加工技术研究 总被引:2,自引:0,他引:2
研究了采用枯草杆菌蛋白酶酶解甲鱼的条件。正交试验分析结果表明:酶解甲鱼的最佳条件是酶用量(E/S)144mg/kg,温度45℃,pH值为7.0时酶解4h,甲鱼酶解液的氨基酸态氮含量由0.0369g/kg增加到0.2265g/kg,增加了6倍;游离氨基酸由51.1g/kg增加到503.3g/kg,增加近10倍。但酶解液中含有大量苦味氨基酸和苦味多肽成分,经接入30g/kg嗜热链球菌(S.t)和保加利亚杆菌(L.b)于42℃发酵4h后,酶解液中苦味天冬氨酸在发酵后减少了近10倍,酶解液风味得到明显改善,苦味基本消失并产生了特殊的发酵香味。甲鱼生物饮料配方是:甲鱼酶解发酵过滤液80g/kg,麦芽糖浆30g/kg,蔗糖45g/kg,稳定剂3g/kg,固形物含量为750g/kg的浓缩果汁80g/kg,酸味调节剂和香精适量。 相似文献
11.
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. 相似文献
12.
John Gilbert Catherine Simoneau David Cote Achim Boenke 《Food Additives & Contaminants》2000,17(10):889-893
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. 相似文献
13.
Sophie Guillot Laurence Peytavi Sylvie Bureau Renaud Boulanger Jean-Paul Lepoutre Jean Crouzet Sabine Schorr-Galindo 《Food chemistry》2006
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. 相似文献
14.
Jesus Simal-Gandara Miguel Sarria-Vidal Arjen Koorevaar Rinus Rijk 《Food Additives & Contaminants》2000,17(8):703-711
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. 相似文献
15.
16.
M. S. Garcí a-Falc n J. Simal-G ndara S. T. Carril-Gonz lez-Barros 《Food Additives & Contaminants》2000,17(12):957-964
A simple, rapid and inexpensive method has been developed for the determination of benzo[a 相似文献
17.
H. J. Van Den Top A. Boenke P. A. Burdaspal J. Bustos H. P. Van Egmond T. Legarda A. Mesego A. Mourino W. E. Paulsch C. Salgado 《Food Additives & Contaminants》2001,18(9):810-824
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. 相似文献
18.
《肉类研究》2014,(2)
<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 相似文献
19.
《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%. 相似文献
20.
《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press 相似文献