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71.
食品中甜蜜素的高效液相色谱法 总被引:1,自引:0,他引:1
本文建立了甜蜜素的高效液相色谱法,结果表明样品中甜蜜素含量为0-1.0 mg/g范围内,峰面积与甜蜜素含量呈良好的线性关系,相关系数为0.9977,对0.1 mg/mL标准溶液连续测定7次,相对标准偏差为3.65%, 加标回收率为95.4%-102.2%之间,食品中共存的苯甲酸、山梨酸、安赛蜜等不影响测定,方法简捷、准确。用于实际样品测定,结果令人满意。 相似文献
72.
本文介绍了随市场经济的建立,我国商业冷库面临的问题、生产方式及储藏业务的变化,就肉类食品在冷库储藏中如何保证其安全性,提出了建议和措施. 相似文献
73.
To maximize the efficiency of cooling and freezing operations for foods, it is necessary to optimally design the refrigeration equipment to fit the specific requirements of the particular cooling or freezing application. The design of food refrigeration equipment requires estimation of the cooling and freezing times of foods, as well as the corresponding refrigeration loads. The accuracy of these estimates, in turn, depends upon accurate estimates of the surface heat transfer coefficient for the cooling or freezing operation. This project reviewed heat transfer data for the cooling and/or freezing of foods. A total of 777 cooling curves for 295 food items were obtained from an industrial survey and a unique iterative algorithm, utilizing the concept of ‘equivalent heat transfer dimensionality’, was developed to obtain heat transfer coefficients from these cooling curves. Nine Nusselt–Reynolds–Prandtl correlations were developed from a selection of the 777 heat transfer coefficients resulting from this algorithm, as well as 144 heat transfer coefficients for 13 food items, collected from the literature. The data and correlations resulting from this project will be used by designers of cooling and freezing systems for foods. This information will make possible a more accurate determination of cooling and freezing times and corresponding refrigeration loads. Such information is important in the design and operation of cooling and freezing facilities and will be of immediate usefulness to engineers involved in the design and operation of such systems. 相似文献
74.
三元硼化物金属陶瓷覆层材料耐腐蚀性能研究 总被引:4,自引:0,他引:4
以Mo粉、FeB合金粉和Fe粉为基本原料,分别加入Cr、Ni、C或同时加入Cr、Ni、C合金元素成分,采用原位反应真空液相烧结工艺,在Q235钢基体上制备三元硼化物金属陶瓷覆层材料。研究了合金组分对覆层材料耐腐蚀性的影响。结果表明,三元硼化物金属陶瓷覆层材料的覆层具有远比钢基体优越的耐蚀性,C组分的单独加入降低了覆层的耐蚀性,Cr、Ni组分的加入显著提高了覆层的耐蚀性,同时加入Cr、Ni、C作为合金组分使覆层具有最佳的耐蚀性。 相似文献
75.
章介绍了交流变频调速原理,并针对传统配料方法所遇到的问题,提出了用交流变频调速系统予以解决的方案。对该系统的主要组成部分的方案配置进行了详细说明。 相似文献
76.
77.
介绍疏水化合孔栓成分的工作机理,结合其特征,在每立方米混凝土中掺入30L疏水化合孔栓成分,配制出东华大桥主墩承台大体积高性能防水抗腐蚀混凝土,采取循环冷却水管降温的方法确保了基础混凝土的施工质量,凝结后混凝土表现出的憎水性显著。 相似文献
78.
The present study explores the concept of mistrust in country of origin information and the use of technology by consumers to corroborate information on food labels. Despite the plethora of food studies on trust conveyed by different sources, there appears to be a lack of studies exploring consumers' willingness to substantiate information on food labels, more specifically country of origin, and how it is influenced by mistrust. A self-administered survey was conducted in the city of Innsbruck, Austria, to evaluate the relationship between mistrust and the willingness to use technology and verify food label information in food stores. This present study suggests that mistrust towards industry and/or regulators in general augments consumers' willingness to self-authenticate. Findings also suggest that highly educated consumers are more likely to distrust the information on food labels, and are more willing to use a device to validate food label content. Expected results suggest that consumers who read labels on a regular basis expressed a higher willingness to self-authenticate, and that women are more likely to read labels than men. Limitations of the study are presented; theoretical significance and practical implications of the findings are also discussed. 相似文献
79.
《Food Control》2014
Zinc oxide (ZnO) nanoparticles have been proven to have strong antibacterial activity against food borne pathogens. The practical applications of different concentrations (0, 1, 3, 5 and 8 mM) of ZnO suspensions containing 0.3% citric acid were investigated against the pathogenic bacteria like, Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Bacillus cereus. Zinc oxide suspensions (0, 1, 3, 5 and 8 mM) containing citric acid have shown a significant inhibitory effect on the growth of all strains during 12 h of incubation. Our results have also shown that 5 and 8 mM suspensions of ZnO were the most effective on all strains. These data suggested that the antibacterial activity of ZnO was concentration dependent. Thus 5 mM and 8 mM ZnO were selected for further studies, carried out in mango juice, as they showed a significant growth inhibition in TSB. ZnO NPs were more capable of reducing initial growth counts of all the above stated strains in mango juice. Results have also exhibited that ZnO and citric acid had inhibitory effect on the growth of all strains during 24 h culture period in mango juice, as compared to the control experiment, which was further confirmed in liquid culture. This is the first report, describing the antibacterial activity of ZnO NPs in mango juices that showed the potential of these nanoparticles for use as an antibacterial agent in the food industry. 相似文献
80.
为加强食品安全监管,一些国家和地区对部分作为农药登记使用的有效成分批准了豁免制订其在食品中的最大残留限量标准。介绍了欧盟、日本、美国、澳大利亚、新西兰、中国台湾和中国香港等的豁免农药名单。 相似文献