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11.
新时期下,保障我国畜产食品供给安全是保障我国食物安全的重要内容之一,而“适度进口”是保障我国畜产食品供给安全的重要途径之一。如何才算“适度进口”,需对畜产食品进口的相关风险进行分析方可评判。运用进口依赖性评价模型对我国猪肉、鸡肉、羊肉、牛肉、鲜牛奶的进口依赖性风险进行分析发现,上述5种畜产食品均存在进口依赖性风险。其中,猪肉的风险来自美国、德国、丹麦、西班牙和加拿大;鸡肉的风险来自美国、巴西、阿根廷和波兰;羊肉的风险来自澳大利亚、新西兰和乌拉圭;牛肉的风险来自乌拉圭、澳大利亚、新西兰、阿根廷和加拿大;鲜牛奶的风险来自德国、法国、新西兰和澳大利亚。为降低我国畜产食品进口依赖性风险,短期内应采取畜产食品进口市场多元化策略以及用进口饲草料替代进口畜产食品的进口方式;长期应在保障“口粮安全”的前提下,调整农业结构,大力发展草地农业,减少对国际市场的依赖性。 相似文献
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K. S. Venturini M. F. Sarcinelli M. A. Baller T. C. Putarov E. B. Malheiros A. C. Carciofi 《Journal of animal physiology and animal nutrition》2018,102(4):1077-1087
Soya bean protein concentrate (SPC) with two particle sizes were evaluated on extrusion parameters, kibble formation, digestibility and palatability of dog foods. Eight diets were extruded: PBM—control diet based on poultry by‐product meal (PBM); GM—a diet in which corn gluten meal (GM) replaced 45% of the diet protein; cSPC15%, cSPC30% and cSPC45%—diets in which SPC of coarse particle size (600 μm) replaced 15%, 30% and 45% of the diet protein; and sSPC15%, sSPC30% and sSPC45%—diets in which SPC of small particle size (200 μm) replaced 15%, 30% and 45% of the diet protein. The digestibility of nutrients was evaluated for the PBM, GM, cSPC45% and sSPC45% diets, using six dogs per food. The PBM, GM and cSPC45% diets were compared for palatability. Data were submitted for analysis of variance, and the means were compared by polynomial contrasts or Tukey's test (p < .05). The cSPC increased the specific mechanical energy (SME) application, extrusion temperature and pressure linearly, resulting in lower kibble density and higher expansion and starch gelatinization (SG) (p < .01). When comparing the PBM, GM, cSPC45% and sSPC45% diets, higher SME, extrusion temperature and pressure, SG and kibble expansion were verified for the cSPC45% diet (p < .05). The DM, fat and crude protein digestibility were similar among diets. Faecal pH, ammonia and lactate did not differ, demonstrating that the removal of oligosaccharides and soluble non‐starch polysaccharides of SPC produces an ingredient with mostly non‐fermentable fibre. Dogs preferred the PBM to the GM diet (p < .05), but consumed the PBM and cSPC45% foods equally. In conclusion, SPC exhibited good extrusion functionality, favouring kibble expansion and SG, with high digestibility, similar to that of PBM. The removal of soluble compounds from soya beans resulted in an ingredient with low fermentable fibre content, which did not alter faecal formation or characteristics. 相似文献
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菜用睡莲营养成分及重金属含量测定与评价 总被引:2,自引:0,他引:2
对绿梗菜用睡莲(Nymphaea tetragona)及红梗菜用睡莲的15营养成分和4种重金属含量进行了测定与评价。结果表明,1与104~140种(品种)新鲜蔬菜已知数据比较,绿梗和红梗菜用睡莲均有较高含量的维生素C、钠及较低含量的干物质、蛋白质、钾、钙、镁、铜、锌、磷及硒;绿梗菜用睡莲有较高含量的粗纤维、锰及较低含量的铁,红梗菜用睡莲有较高含量的铁及较低含量的粗纤维。2菜用睡莲是一种含钠量较高的蔬菜。3绿梗菜用睡莲营养成分含量总体高于红梗菜用睡莲。4湖北产区菜用睡莲的铅、砷、镉及汞等重金属含量符合食品安全国家标准的规定。 相似文献
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利用微胶囊技术,可以解决传统工艺所不能解决的众多问题,生产出多种高新产品,且具有良好的功能性质和贮存稳定性。介绍微胶囊技术的特点,壁材、芯材的类型,制备方法、原理,以及其在饮料工业、乳制品、糖果、食品添加剂以及焙烤食品中的应用。 相似文献
17.
食品安全是天大的事,培养相关的专业人才尤显重要。依据食品质量与安全专业人才培养目标要求明确专业内涵,采用模块设计方法构建食品质量与安全专业课程体系,并就如何提高人才培养质量提出建议。 相似文献
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In this study, the changes in vitamin C, l-ascorbic acid (AA) and l-dehydroascorbic acid (DHA) levels in broccoli flower buds were examined during pre-storage and storage periods, simulating refrigerated transport with wholesale distribution and retail, respectively. Broccoli heads were pre-stored for 4 or 7 days at 0 °C or 4 °C in the dark and then stored for 3 days at 10 °C or 18 °C. During storage the broccoli heads were exposed for 12 h per day to three different levels of visible light (13, 19 or 25 μmol m−2 s−1) or a combination of visible light (19 μmol m−2 s−1) and UV-B irradiation (20 kJ m−2 d−1), or they were stored in the dark. The vitamin C content in broccoli flower buds during storage was significantly affected by pre-storage period and temperature. Higher vitamin C levels in flower buds after storage were observed for broccoli heads pre-stored for 4 days or at 0 °C as compared to those pre-stored for 7 days or at 4 °C. Storage temperature also affected vitamin C in broccoli flower buds, with higher levels observed for broccoli stored at 10 °C than at 18 °C. Hence, vitamin C in broccoli flower buds was demonstrated to decrease together with increasing pre-storage period, pre-storage temperature and storage temperature. AA in broccoli flower buds was influenced mainly by storage temperature and to a minor extent by pre-storage temperature. The DHA level and DHA/AA ratio were stable in flower buds of broccoli pre-stored for 7 days, whereas increasing tendencies for both DHA level and ratio were observed after pre-storage for 4 days. These results indicate a shift in the ascorbate metabolism in broccoli flower buds during storage at low temperatures, with its higher rate observed for broccoli pre-stored for shorter time. There were no effects of the light and UV-B irradiation treatments on vitamin C, AA and DHA levels in broccoli flower buds. 相似文献
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Nitrofurans are broad-spectrum antibiotics which have been widely used in food animals to the prevention and treatment of gastrointestinal infections.Due to abuse of drugs by criminals,animals could produce drug-resistant strains,which reduces the role of antibiotics.Meanwhile,excessive drugs residues in food has carcinogenic,teratogenic and mutagenic effects to the human body.In this paper,the damage and the detection methods of the residues of the nitrofurans in food are surveyed.The main detection methods include high performance liquid chromatography,liquid chromatography-mass spectrometry,liquid chromatography tandem mass spectrometry,enzyme-linked immunoassay,colloidal gold immunoassay and fluorescence immunity analysis method.The research status of various detection methods are summarized and the suggestions for further research are put forward.It is expected to provide reference for future research. 相似文献