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71.
肉制品加工过程中往往伴随着脂质氧化的发生,现有研究表明,脂质氧化能影响肉制品中杂环胺、N-亚硝基化合物、晚期糖基化终末产物及多环芳烃等有害物质的生成,这些物质的积累会降低肉制品的食用安全性并危害人体健康。本文综述了肉制品中脂质氧化的机制及氧化产物的反应活性、脂质氧化对肉制品中上述4 类有害物质形成的影响及相关控制措施,以期从控制脂质氧化的角度出发为肉制品安全性生产工艺提供参考。  相似文献   
72.
BackgroundGlobal public concerns about “industrial agriculture” have widely disseminated amongst consumers the myth that chickens are fed growth hormones to produce meat more efficiently. This misleading information regarding the use of hormones in chickens is now a growing health concern among consumer groups.Scope and ApproachWorldwide, the poultry industry relies on science and technology to define new strategies to improve the health, welfare and performance of animals in production. In this report, we performed a detailed analysis of the poultry science literature and provide the scientific bases explaining why chickens are not feed hormones.Key Findings and ConclusionsThe use of growth hormones in poultry meat production does not occur because: i) they are too expensive to be used in chickens, ii) they do not promote growth in poultry and iii) their use is illegal in many countries. Therefore, health providers, policy makers, food professionals, consumer advocates, food producers and veterinarians can use this information to educate consumers and eliminate negative concerns related to hormone use in the poultry industry.  相似文献   
73.
Carne do alguidar is a Portuguese traditional pork fried meat, usually manufactured for self‐consumption purposes. This study developed a ready‐to‐eat (RTE) meat product, to meet today's consumers’ convenience, manufactured at the industrial scale evaluating its quality and shelf life, assessing the effect of vacuum packaging and the use of an antioxidant (50 ppm BHT) to enhance oxidative stability. Physicochemical and microbiological parameters were assessed, and a sensory analysis was performed. Interestingly, no significant differences were recorded between control (non‐BHT) and antioxidant (BHT) samples. Microbiological counts remained at low levels throughout the storage period, ensuring the product's required microbiological quality. At later storage stages, higher values of thiobarbituric acid‐reactive substances arose and off flavours and aromas were perceived. Still, overall appreciation was not affected until 12 months of storage and a significant depreciation was perceived only after 15 months. Fibrousness and rising of off flavours were negatively correlated with overall appreciation.  相似文献   
74.
This study was aimed at evaluating the consequences of sodium chloride reduction by potassium chloride up to 50% on technological, sensorial and microbiological traits of marinated rabbit meat. In total, 226 rabbit loin meat samples were obtained and subjected to vacuum tumbling using solutions with different NaCl/KCl ratios. Replacing of sodium chloride up to 30% by potassium chloride did not change microbiological traits (total aerobic mesophilic and lactic acid bacteria maximum cell loads), sensorial acceptability (perceived saltiness and overall liking) and technological traits (pH, colour, texture, cooking loss and yield). Otherwise, reduction in sodium chloride to 50% significantly decreased perceived saltiness (4.15 vs. 4.73; P < 0.05) and reduced microbial shelf life by 1 day when compared to control, even if there was still no effect on technological traits. In conclusion, it is feasible imparting an added value for processed rabbit meat products by reduction in sodium content that could increase market interest.  相似文献   
75.
The objective of the study was to evaluate the impact of birds’ sex on the carcass composition and meat (breast muscle) nutritional value in Japanese quails in a large‐scale four‐generation study. Standard poultry feed was used, based on maize, soya bean meal and wheat. Four generations of quails were housed up to the age of 17 weeks each. Then samples of breast muscle were collected after dissection and analysed for basic nutrient content and for fatty acids composition. Results were analysed by GLM procedure in SAS, and significance of differences between birds of different sex was estimated by Duncan's test. Dissection revealed marked differences between birds’ of different sex in case of relative organ weight. Results of meat analyses showed no differences in the basic composition. Fatty acids analyses showed a more advantageous profile in female meat.  相似文献   
76.
The worldwide consumption of meat is increasing, especially in developing countries. Many studies have correlated a diet characterised by high intake of processed red meats with a risk of colorectal cancer, stroke, coronary heart diseases and diabetes. Moreover, the quality and safety of meat products may be compromised by several admitted and not admitted procedures (i.e. addition of food additives and/or foreign proteins). For these reasons, the topic ‘meat products’ quality and safety’ has gained much in importance during last few years. In this review, the recent advances in the field of analytical methods for the evaluation of meat adulteration due to the addition of foreign proteins and food additives are reported, compared and critically evaluated. Moreover, the most representative monitoring practices, developed worldwide, related to meats adulteration are described and discussed.  相似文献   
77.
Mitochondria are complex organelles that play critical roles in diverse aspects of cellular function. Heart disease and a number of other pathologies are associated with perturbations in the molecular machinery of the mitochondria. Therefore, comprehensive, unbiased examination of the mitochondrial proteome represents a powerful approach toward system-level insights into disease mechanisms. A crucial aspect in proteomics studies is design of bioanalytical strategies that maximize coverage of the complex repertoire of mitochondrial proteins. In this study, we evaluated the performance of gel-based and gel-free multidimensional platforms for profiling of the proteome in subsarcolemmal mitochondria harvested from rat heart. We compared three different multidimensional proteome fractionation platforms: polymeric reversed-phase liquid chromatography at high pH (PLRP), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and isoelectric focusing (IEF) separations combined with liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS), and bioinformatics for protein identification. Across all three platforms, a total of 1043 proteins were identified. Among the three bioanalytical strategies, SDS-PAGE followed by LC-MS/MS provided the best coverage of the mitochondrial proteome. With this platform, 890 proteins with diverse physicochemical characteristics were identified; the mitochondrial protein panel encompassed proteins with various functional roles including bioenergetics, protein import, and mitochondrial fusion. Taken together, results of this study provide a large-scale view of the proteome in subsarcolemmal mitochondria from the rat heart, and aid in the selection of optimal bioanalytical platforms for differential protein expression profiling of mitochondria in health and disease.  相似文献   
78.
Successfully engaging consumers in a dialogue may provide opportunities for better tailored and more effective communication about food-related risks and benefits. Using an online deliberation concept and software, VIZZATA™, we explored the validity of a behavioral measure of deliberation in an online environment in the context of consumers’ perceptions and information seeking about the risks and benefits of red meat. Participants from Belgium, Portugal and the United Kingdom (n = 150) were given the opportunity to engage in an asynchronous interaction with the research team about the information provided. Online deliberation was operationalized as an individual metric based on the number of questions asked in relation to the information, the number of comments left, the number of glossary terms accessed, and the time spent on deliberative activity. This operationalization provided a coherent measure of deliberation which was positively correlated with information recall about the risks and benefits of red meat. Participants who perceived the information about red meat risks and benefits as too complex engaged less with the information. The study herewith presents a novel method of investigating consumers’ deliberation about food issues that conceptualizes consumer engagement as more than just information seeking.  相似文献   
79.
In this study, a possible use of aloe gel (AG) as a potential fat replacer in the manufacture of low‐fat meat emulsion was investigated. The low‐fat meat emulsions with added AG and vegetable oil (VO) in different proportions [AG7.5 (7.5% AG + 7.5% VO); AG5 (5% AG + 10% VO); AG2.5 (2.5% AG + 12.5% VO)] were compared with full‐fat meat emulsion [Control (15% VO only)]. A substantial fat reduction (< 0.05) up to 50% as compared to full‐fat control meat emulsion was recorded without compromising other sensory attributes of meat emulsion. Microstructural properties as studied by scanning electron microscopy indicated more homogenous regular emulsion matrix with fewer cracks and more regular shaped oil droplets in AG‐added samples than the control samples.  相似文献   
80.
The stability of antioxidant peptides from aged duck meat during processing and simulated gastrointestinal digestion was investigated. The antioxidant peptides preserved a high stability in the presence of diverse NaCl or upon various time heating. The antioxidant activities were strengthened by the addition of 4–8% glucose or by heating at 100 °C, whereas they were lost under alkaline conditions. During in vitro digestion, the antioxidant activities increased with pepsin treatment but then decreased following trypsin digestion. Pepsin hydrolysed peptides into short fragments and results in the increased exposure of internal hydrophobic amino acids. With further treatment by trypsin, peptides can be hydrolysed completely and more free amino acids were released, leading to the decline in surface hydrophobicity. These variations might be responsible for the change in antioxidant activity during in vitro digestion. The antioxidant peptides from aged duck with high stability can be used as functional food ingredients to improve human health.  相似文献   
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