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排序方式: 共有4671条查询结果,搜索用时 671 毫秒
91.
Arun Kumar Rajiv Ranjan Kumar Brahm Deo Sharma Sanjod Kumar Mendiratta Deepak Sharma 《Critical reviews in food science and nutrition》2015,55(10):1340-1351
The adulteration/substitution of meat has always been a concern for various reasons such as public health, religious factors, wholesomeness, and unhealthy competition in meat market. Consumer should be protected from these malicious practices of meat adulterations by quick, precise, and specific identification of meat animal species. Several analytical methodologies have been employed for meat speciation based on anatomical, histological, microscopic, organoleptic, chemical, electrophoretic, chromatographic, or immunological principles. However, by virtue of their inherent limitations, most of these techniques have been replaced by the recent DNA-based molecular techniques. In the last decades, several methods based on polymerase chain reaction have been proposed as useful means for identifying the species origin in meat and meat products, due to their high specificity and sensitivity, as well as rapid processing time and low cost. This review intends to provide an updated and extensive overview on the DNA-based methods for species identification in meat and meat products. 相似文献
92.
鸡肉酶解过程中呈味成分变化规律研究(英文) 总被引:1,自引:0,他引:1
本文研究了Alcalase水解鸡肉过程中其呈味成分变化规律。在整个酶解过程中,游离氨基酸和可溶性氮含量一直以不同趋势增加,而肽含量则在前16h增加,然后缓慢降低。鲜/甜味、苦味氨基酸的组成与含量对鸡肉酶解产物的最终风味有很大的影响。酶解产物中的糖在酶解2h后达到最大值,然后总体上表现为下降趋势。由于酶解产物中糖量较低,其对酶解产物的风味影响不大,但其对产物颜色有重要影响。酶解中,pH在前20min内显著下降,然后减势变缓直到几乎保持恒定,这表明酶解产物的缓冲能力明显增强。 相似文献
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Tzu Tai Lee Jhih Ying Ciou Chung Li Chen Bi Yu 《Journal of the science of food and agriculture》2013,93(1):166-172
BACKGROUND: Echinacea purpurea L. (EP) is a popular herbal antioxidant and immunomodulator. The present study was conducted to evaluate the effects of EP on meat quality and oxidative status in broilers. Two hundred and fifty (1‐day‐old) male broilers (Arbor Acres) were randomly allocated to five groups including the control (corn‐soybean meal diet) and 0.1, 0.5, 1.0 and 2.0% EP powder groups, with two replicates per treatment group. RESULTS: The results indicated that the addition of 0.5% and 1.0% EP significantly increased water‐holding capacity and decreased storage loss of breast and thigh fillets at 35 days old. For fillet colour, L* (lightness) values were lower, and a* (redness) and b* (yellowness) values were higher with EP supplementation. Lower crude fat contents were observed in EP groups in comparison with control at 35 days of age in breast and thigh fillets, respectively. Production of malondialdehyde was slightly reduced in serum of EP supplemented birds compared to the control group. Results for Trolox equivalent antioxidant capacity, catalase and superoxide dismutase were significantly higher for the 0.5, 1.0 and 2.0% EP supplemental groups than control group in serum. Liver and spleen tissues results showed that the antioxidative enzymes activities were higher with EP powder at 35 days of age. CONCLUSION: Dried EP can be used as a feed additive to improve the meat quality and oxidative status in Arbor Acres broilers. Copyright © 2012 Society of Chemical Industry 相似文献
96.
目的:建立肉制品中单增李斯特菌环介导间接聚合酶链式反应检测体系,实现快速检测。方法:采用Chelex法从肉制品中分离模板DNA,根据单增李斯特菌hlyA基因的保守区设计两条探针,将探针标记于报告基因(大豆Lectin基因)的两端,此标记的报告基因与待测靶基因经杂交、缺口补平、环化后,采用反向聚合酶链式反应扩增报告基因,实现对靶基因的检测。结果:该检测体系检出限低于100CFU/g(mL),且与其他食源性致病菌的检测无明显交叉反应,对200份肉制品进行检测,阳性率为2.5%,与传统细菌分离检测结果完全相符。结论:环介导间接聚合酶链式反应可以快速、灵敏、特异检测肉制品中单增李斯特菌污染。 相似文献
97.
《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(9):1215-1220
An analytical method for the simultaneous determination of Sudan dyes (Sudan Red G, Sudan I, Sudan II, Sudan III, Sudan Red 7B and Sudan IV) and Para Red in food by ultra-performance liquid chromatography-electrospray tandem mass spectrometry (UPLC-ESI-MS/MS) was developed. Samples were extracted with acetonitrile, and water added into the extract. The supernatant was analysed by UPLC-MS/MS after refrigeration and centrifugation. The sample was separated on an Acquity BEH C18 column, and detected by MS/MS with the multiple reaction monitoring mode. Matrix calibration was used for quantitative testing of the method. The linear matrix calibrations of Sudan dyes and Para Red were 2–50 and 10–250 ng g?1, respectively, and the regression coefficients were >0.9945. The recoveries were 83.4–112.3% with good coefficients of variation of 2.0–10.8%. The limits of detection were between 0.3 and 1.4 ng g?1 for the six Sudan dyes, and between 3.7 and 6.0 ng g?1 for Para Red. The limits of quantification were between 0.9 and 4.8 ng g?1 for the six Sudan dyes, and between 12.2 and 19.8 ng g?1 for Para Red. 相似文献
98.
目的研究膜芯片技术检测肉类及其制品中动物源性成分,验证该技术的准确性及可行性。方法利用膜芯片检测肉制品中的动物源性成分,对样品中猪、牦牛、驴及羊源性成分的灵敏度、检出限进行相关实验,并就实际样品的检测与国家标准进行比较。结果该技术用于动物源性成分检测特异性良好,4种动物源性检测的灵敏度为0.1 ng,检出限为0.1%(w:w),适用的样品种类较广,实际样品的检测结果与国家标准荧光PCR法一致。结论该技术可作为快速筛选的方法,为肉制品的动物源性成分鉴定和掺假检测提供理论依据。 相似文献
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