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不同部位冷却猪肉中脂肪酸组成与脂肪氧化的变化 总被引:4,自引:0,他引:4
研究英系大白阉公猪后腿肉、里脊肉和五花肉3个部位中肌间脂肪和皮下脂肪含量,并对其脂肪酸组成进行了分析,同时研究了腿肉在(4±0.5)℃避光贮存条件下脂肪氧化程度的变化,及其与脂肪酸组成的关系。结果表明,不同部位猪肉肌间和皮下脂肪酸组成均没有显著性差异(p>0.05);在(4±0.5)℃避光贮存期间(0~5d),肌间脂肪氧化程度显著高于皮下脂肪氧化程度(p<0.05),随着贮存时间的延长,到第5天时,后腿肉肌间脂肪TBA值已达到0.5mg/kg,其它部位肌间脂肪TBA值亦接近0.5mg/kg,而各部位皮下脂肪TBA值均在0.2mg/kg以下。一般来讲,当生肉的TBA值超过0.5mg/kg时,人就能感觉到有氧化异味。因此,控制肌间脂肪氧化是保证冷却肉良好品质的关键。 相似文献
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猪腿肉脂肪酸组成及脂肪氧化的研究 总被引:9,自引:0,他引:9
本文研究了不同性别英系大白腿肉中肌间脂肪和皮下脂肪含量,并对其脂肪酸组成进行了分析,同时研究了腿肉在(4±0.5)℃避光贮存条件下脂肪氧化程度的变化,结果表明,不同性别猪腿肉肌间和皮下脂肪酸组成及含量均没有显著性差异(p>0.05);在(4±0.5)℃避光贮存期间(0~5d),肌间脂肪氧化程度显著高于皮下脂肪氧化程度(p<0.05),尤其到第5d时,肌间脂肪氧化指标-TBA值接近0.5mg/kg,而皮下脂肪TBA值低于0.2mg/kg。一般来讲,当生肉的TBA值超过0.5mg/kg时,人就能感觉到有氧化异味。因此,控制肌间脂肪氧化保证冷却肉良好品质的关键。 相似文献
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光对冷却肉脂肪氧化和色泽变化的影响 总被引:6,自引:4,他引:2
本文研究了不同光性质对脂肪氧化变化和色泽变化的影响。研究发现,选择照明光源(日光灯和白炽灯)时应根据贮存温度而定,在4±2℃温度下贮存时,两种光源对脂肪氧化程度影响之间不存在显著性差异(p>0.05),但日光灯照明可以延缓颜色发生变化,而在9±1℃温度下贮存时,采用白炽灯照明较适,可延缓脂肪氧化和变色发生。在4±2℃贮存温度下,采用日光灯照明时,光照强度低于750lux的情况下,光强大小对猪肉脂肪氧化和色泽变化的影响较小。在4±2℃贮存温度下,激发波长低于550nm的蓝光和绿光能明显加快猪肉脂肪氧化和变色。 相似文献
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以牦牛脂肪为研究对象,硫代巴比妥酸反应产物(TBARS)为氧化指标,研究了不同光照和温度对牦牛脂肪初期氧化的影响。结果表明:牦牛脂肪初期氧化发生于0~25 d((15±1)℃);在氧化初期,光照度为20 lx、不透光材料包装下脂肪TBARS的变化明显较964 lx、半透光材料包装及1 550 lx、全透光材料包装下平缓,且有15 d左右的滞后期,脂肪TBARS受非避光比避光影响大;(4±1)℃TBARS的变化明显滞后于(15±1)℃,且滞后期为10 d,反映出较低温度能明显抑制过氧化物的生成速度,最终影响TBARS,推迟脂肪氧化;(9±1)℃TBARS变化介于(4±1)℃和(15±1)℃之间,反映出温度对脂肪氧化的改变是温和均匀的。 相似文献
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以精炼米糠油为原料,通过分析其理化指标与脂肪酸组成,探讨贮藏条件对米糠油氧化稳定性的影响,建立氧化反应动力学方程,预测米糠油的货架期。结果表明,米糠油脂肪酸中不饱和脂肪酸含量为77.45%,主要有棕榈酸17.77%、油酸46.74%、亚油酸29.34%。米糠油的氧化稳定性受光照、温度和氧气含量的影响,空气中氧气的存在会加速米糠油氧化,温度越高,氧化速度越快;不同光照条件下的稳定性依次为:避光>紫外光>自然光>日光灯。米糠油氧化遵循一级化学反应,其动力学模型为RTk e796.360.3564=,通过外推法得出米糠油20℃、25℃和30℃的货架期分别为1068 d、410 d、206 d。 相似文献
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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
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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
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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
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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
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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
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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
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《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
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《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
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《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