Importance of animal products in the human diet.

Increased interest in food, nutrition, and health has led to critical evaluation of the American diet by governmental, scientific, and consumer groups. The exact role of diet in health and disease continues to be debated. Over the years trends in consumption of foods and nutrients have developed. These issues are examined. Historically, animal products have played a key role in the overall health of Americans. The contributions of animal products to human nutrition are emphasized along with an introduction to the use of the concept of nutrient density.     

Nitrates, nitrites and N-nitrosocompounds: a review of the occurrence in food and diet and the toxicological implications

Data on occurrence of nitrate, nitrite and N-nitrosocompounds in food and drinking water, and on total dietary intakes are reviewed. Metabolic, toxicological and epidemiological studies are surveyed and the implications with respect to safety evaluation are addressed. It is concluded that, on the basis of recent long-term animal studies and of clinical experience in man, the current Acceptable Daily Intake (ADI) allocated to nitrate by the Joint FAO/WHO Expert Committee on Food Additives of 0-5 mg/kg body weight/day (expressed as sodium nitrate) might be increased to 0-25 mg/kg body weight/day. Based on similar criteria, the ADI for nitrite would be 0-0.1 mg/kg body weight/day (expressed as sodium nitrite). In view of the known carcinogenicity of N-nitrosocompounds, exposure to these compounds in food should be minimized by appropriate technological means, such as lowering the nitrite concentration in preserved foods to the minimum required to ensure microbiological safety and use of inhibitors of nitrosation like alpha-tocopherol or ascorbic acid. Further work is needed to define the minimal levels of nitrite in foods needed to inhibit outgrowth of Clostridium botulinum and toxin production.     

Importance of maternal diet in the training of the infant's immune system during gestation and lactation

Latest forecasts predict that half of the European population will be allergic within the coming 15 years, with food allergies contributing substantially to the total burden; preventive measures are urgently needed. Unfortunately, all attempted alimentary strategies for primary prevention of allergic diseases through allergen avoidance so far have failed. This also holds true for the prevention of food allergies in breastfed infants by the common practice of excluding certain foods with allergenic potential from the maternal diet. As a preventive measure, therefore, exclusion diets should be discouraged. They can exhaust nursing mothers and negatively impact both their nutritional status as well as their motivation to breastfeed. A prolonged exclusion diet may be indicated solely in cases of doctor-diagnosed food allergy following rigid medical tests (e.g. double-blind placebo-controlled food challenges). Indicated cases usually involve exclusion of only a few food items. Continued breastfeeding is generally important for many aspects of the infant's health, including the training of the infant's immune responses to foreign compounds and avoidance of overshooting inflammatory responses. Recent studies suggest that the presence of maternal dietary proteins in amniotic fluid, cord blood, and human milk might support the induction of tolerance towards solid foods in infants. These are exactly the same species of proteins or remnants thereof that, in comparatively few cases, trigger allergic responses. However, the insight that the proteins of maternal dietary origin in human milk are more likely to be cure (or, more precise, directing prevention) than curse has still largely evaded the attention of health care professionals consulted by worried breastfeeding mothers. In this paper, we summarize recent literature on the importance of exposure to dietary proteins in the establishment of immunological tolerance and hence prevention of allergic disease. Multiple organizations have used the scientific knowledge to build (local) guidelines (e.g. AAAAI, EAACI, BSACI) that can support health care professionals to provide the best strategy to prevent the onset of allergic diseases. We thus hope to clarify existing confusion about the allergenic propensities of dietary proteins during early life, which has contributed to exaggerated fears around the diet of pregnant and breastfeeding mothers.     

烟草毒理研究进展

从体外试验和体内实验两方面,在生物大分子水平、细胞水平和整体水平等层次,概述了近几年烟气一般和特殊毒性作用及其作用机制的研究成果。      

三聚氰酸毒理学研究进展

三聚氰酸是三聚氰胺的同类物,它与三聚氰胺在一定条件下形成结晶,在人和动物体内这种结晶易于对膀胱和肾脏造成损伤.本文对三聚氰酸的毒理学安全性资料(包括代谢、急性毒性、遗传毒性、亚慢性毒性、慢性毒性和致癌性)、与三聚氰胺的联合作用以及人群可能暴露水平进行综述.     

Nutritional and toxicological aspects of the Maillard browning reaction in foods

The Maillard, or nonenzymatic, browning reaction between carbonyl and amino groups is a common reaction in foods which undergo thermal processing. The Maillard reaction is a desirable consequence of many industrial and domestic processes and is responsible for the attractive flavor and brown color of some cooked foods. An early recognized consequence of the Maillard reaction was the destruction of some essential amino acids, such as lysine. More recently, research interest has focused on the production of toxic and antinutritive compounds. This review examines the nutritional and toxicological consequences of the Maillard reaction in light of the findings of such research. In particular, the effect of Maillard reaction products on the digestion, absorption, and excretion of nutrients is considered. The cytotoxicity, mutagenicity, and immunochemical aspects of selected Maillard reaction products are also examined and suggestions are made for future areas of investigation.     

The contribution of fruits and vegetables to dietary intake of polyphenols and antioxidant capacity in a Mexican rural diet: Importance of fruit and vegetable variety

There is mounting evidence of the health-protective role of the consumption of fruits and vegetables, which are the major contributors to dietary polyphenol intake. Lack of knowledge about the consumption of phytochemicals in the Mexican diet makes it difficult to evaluate their health significance. The aim of this study was therefore to estimate the contribution of fruit and vegetable consumption to dietary polyphenol intake and dietary antioxidant capacity in a rural population in Mexico. Despite a low intake of fruits and vegetables (< 400 g/day) in the Mexican rural diet, the mean daily intake of dietary polyphenols (> 800 mg/day) and dietary antioxidant capacity (1000-2000 ??mol trolox equivalents/day) from fruits and vegetables was similar to those determined in the Spanish Mediterranean diet. Local fruits and vegetables consumed in the Mexican rural diet are rich in polyphenols with antioxidant properties and are important source of bioactive compounds and dietary fibers. Fruit and vegetable intake needs to be promoted and lifestyle and environmental factors enhanced to improve the health status of obese Mexican rural populations.     

一种植物果实提取物的抑菌实验研究

本文对一种天然植物果实提取物的抑菌实验进行了初步研究。实验证明，该提取物具有很强的防腐作用，对中性食品如牛奶、豆浆、茶饮料等都有较好的抑菌作用，尤其是对鲜肉和肉制品具有很好的防腐保鲜功能，且该提取物具有耐121℃高杀菌的性质，这为其在食品加工生产中的应用提供了很好的基础，具有较大的开发价值。     

Importance of Sensory Evaluation in the Stability Testing of a Medical Food

A medical food was formulated as a dry powder product containing free essential amino acids, fat and carbohydrates. Samples were stored at 4°C, 25°C, and 40°C and evaluated periodically during storage. Proximate analysis, pH, amino acid analysis, osmolarity, emulsion stability, Hunter color difference, and sensory evaluation tests were performed. Changes could not be detected by the chemical tests employed, but were manifested in sensory analysis. This study indicated that sensory testing of medical foods is a critical tool in the assessment of product stability and must be considered an integral part of any medical food stability program. Chemical analysis alone will not provide sufficient data to allow prediction of either patient acceptance or product integrity.     

一氧化碳在水产品中的应用技术及其安全性分析

采用一氧化碳(CO)对水产品进行护色保鲜处理的技术逐渐在国内外水产加工业中盛行,并形成较完善的工艺技术,但CO发色技术的安全性一直备受争议。本文就水产品CO发色的机理和功能、发色产品的检测技术、发色技术的应用现状及发色技术的安全性等问题进行分析,客观评价发色水产品中CO残留及其可能对人体健康造成的危害,针对水产品CO发色技术存在的问题提出了相应的对策和建议。本文旨在为水产品加工企业提供相关指引,为国家相关决策部门提供参考,对促进水产品护色保鲜技术进步及行业良性发展具有重要意义。