虹膜识别在肉类食品安全追溯系统中的应用及关键技术研究

为了提高大型动物肉类食品的安全性,在研究肉类食品供应链的安全管理的基础上,将大型动物的虹膜识别技术引入食品供应链管理中,构建基于虹膜识别的大型动物肉类食品安全可追溯系统,达到肉类食品安全信息查询及出现安全问题后的个体溯源的目的。借鉴人眼虹膜识别的相关技术,以牛眼为例对大型动物虹膜识别的相关算法和虹膜定位等关键技术进行研究,运用改进的Sobel算子对图像进行边缘检测;引入二次B样条曲线算法实现了牛眼虹膜的精确定位;分析牛虹膜纹理特征的分布特点,实现了虹膜特征区域的提取及归一化处理。研究成果对大型动物的虹膜识别研究和肉类食品供应链安全管理具有一定的参考意义。     

农林废弃物在去除废水重金属中的环境友好利用

评述了近年来国内外利用廉价农林废弃物去除废水重金属的研究进展.重点论述了化学改性处理的农林废弃物对重金属离子的吸附性能,并详细比较了改性前后及各种改性方法的吸附效率.改性处理明显提高了农林废弃物的吸附性能,一些改性的农林废弃物吸附剂对某些重金属离子具有良好的吸附性能,显示出广阔的应用前景.但在今后的研究中还应强化改性农林废弃物吸附剂表面结构表征、吸附作用机理和动力学的研究,开发新型高效的改性再生方法,并对废水处理成本进行详细评估.     

耐热乳杆菌的分离及在食物垃圾乳酸发酵中的应用

食物垃圾在我国城市生活垃圾中占有较大比重.发酵食物垃圾生产乳酸是实现其资源化的有效方法.从厌氧发酵的食物垃圾中分离到一株耐热乳酸菌TY50,根据形态、生理生化特征和16S rDNA序列,确定该菌株属于乳杆菌属的干酪乳杆菌组群(Lactobacillus casei group),其最高生长温度为52℃.TY50发酵食物垃圾生产乳酸的最佳同液比为1:12,最适温度为45 ℃.在pH 5.5～6.0条件下,发酵食物垃圾产生36.29 g/L的乳酸,乳酸体积产牢和转化率(乳峻/垃圾干重)分别达到1.01 g/(L·h)和0.44.     

利用餐饮业废油脂制造生物柴油

世界的石油产量将会逐渐减少,石化柴油燃烧后所排放的废气是造成的城市空气污染的主要原因,生物柴油是石化柴油很好的替代能源,文章介绍了国外废油脂处理利用和甸餐饮业废油脂的概况,提出了利用餐饮业废油脂制造生物柴油的方法和工艺流程,并讨论了利用餐饮业废油脂制造生物柴油的几个问题。     

进口含金属物料的固体废物鉴别方法研究

基于已完成的112例进口含金属物料的固体废物鉴别实践,系统地介绍了进口含金属物料的申报品名及各品名所占比例,种类及各种类的特征、固体废物鉴别关键方法和每种鉴别结果所占比例,其中申报品名主要为矿石(砂),所占比例为51.8%;鉴别结果主要为冶炼渣,所占比例为37.5%。提出对于进口的含金属物料,通过测量主要成分和含量、最主要金属元素及典型重金属元素的含量、物相组成、矿相组成,对于极细的粉末等特殊物料,还需要粒度分析等辅助试验,确定其产生来源。如果确定属于金属冶炼过程中产生的副产物、污染控制设施或环境治理过程中产生的物料、含金属废料简单加工处理产物、矿物采选过程中产生的废弃物,那么鉴别物料属于固体废物。     

基于产生来源的固体废物鉴别研究

通过对美国、欧盟和日本的固体废物定义和范围,以及已完成的固体废物鉴别实例的研究,指出固体废物鉴别的关键点在于产生来源分析。提出依据产生来源,固体废物可以分为丧失原有使用价值的物质、生产过程中产生的副产物类物质、环境治理和污染控制过程中产生的物质、其他类物质4大类。如果待鉴别物质的产生来源属于该4大产生来源中的任何一类,则其属于固体废物。     

Factors affecting the quantitative uncertainty of the estimated short-term intake. Part I—Calculation methods

ABSTRACT

The calculation of the combined uncertainty of the international estimated short-term intake (IESTI) of ethephon residues in apples is shown as an example. The ethephon residues in apples were reported by the Joint FAO (Food and Agriculture Organization of the United Nations)/WHO (World Health Organization) Meeting on Pesticide Residues (JMPR). The apple consumption data were taken from the IESTI (international short-term intake) calculation template used by the JMPR. The IESTI was calculated with the currently used method (case 2a) and a proposed one recommended by the EFSA (European Food Safety Authority)/RIVM (Dutch National Institute for Public Health) Scientific Workshop co-sponsored by FAO and WHO. In this example, the ratio of IESTI_proposed/IESTI_current and their combined relative uncertainty are about 2.8, and 1.7, respectively. The larger IESTI and uncertainty obtained with the proposed equation are the consequence of calculation only with the large portion (LP) instead of its combination with unit mass, and the MRL instead of the highest residue (HR). The LP is the major contributor to the combined uncertainty. Both the calculated IESTI and its combined uncertainty depend on the actual food – pesticide residue combination, and should be calculated for each case.     

油脂对污泥和餐厨垃圾厌氧消化的影响

探究了油脂对污泥和餐厨垃圾厌氧消化性能的影响。结果表明,油脂对污泥和餐厨垃圾厌氧消化的影响与油脂的含量相关。当油脂质量分数由0提高至30%时,生物气的产量(以挥发性悬浮固体VSS计)也由385 m L/g提高至489 m L/g,然而继续升高油脂含量会抑制生物产气。机理分析表明,适当提高油脂含量能够提高有机物的溶出、VSS的减量以及挥发性脂肪酸(VFA)的积累,从而为微生物提供了良好的条件。过高含量的油脂会抑制有机物溶出和VFA的积累。     

Comprehensive estimate of the theoretical maximum daily intake of pesticide residues for chronic dietary risk assessment in Argentina

A chronic dietary risk assessment for pesticide residues was conducted for four age groups of the Argentinian population following the procedure recommended by the WHO. The National Theoretical Maximum Daily Intake (NTMDI) for 308 pesticides was calculated for the first time, using the Maximum Residue Limits (MRLs) from several Argentinean regulations and food consumption data from a comprehensive National Nutrition and Health Survey. The risk was estimated by comparing the TMDI with the Acceptable Daily Intakes (ADI) identified by various sources. Furthermore, for each of the compounds with a TMDI >65% of the ADI, a probabilistic analysis was conducted to quantify the probability of exceeding the ADI. In this study 27, 22, 10, and 6 active ingredients (a.i.) were estimated to exceed the 100% of the ADI for the different population groups: 6–23 month-old children, 2–5 year-old children, pregnant women, and 10–49 year-old women, respectively. Some of these ADI-exceeding compounds (carbofuran, diazinon, dichlorvos, dimethoate, oxydemeton-methyl and methyl bromide) were found in all four of these groups. Milk, apples, potatoes, and tomatoes were the foods that contributed most to the intake of these pesticides. The study is of primary importance for the improvement of risk assessment, regulations, and monitoring activities.     

Risk estimation to human health caused by the mercury content of Sushi and Sashimi sold in Japanese restaurants in Brazil

Although fish is a healthy alternative for meat, it can be a vehicle for mercury (Hg), including in its most toxic organic form, methylmercury (MeHg). The objective of the present study was to estimate the risk to human health caused by the consumption of sushi and sashimi as commercialized by Japanese food restaurants in the city of Campinas (SP, Brazil). The total Hg content was determined by atomic absorption spectrometry with thermal decomposition and amalgamation, and the MeHg content calculated considering that 90% of the total Hg is in the organic form. The health risk was estimated from the values for the provisional tolerable weekly ingestion (PTWI) by both adults and children. The mean concentrations for total Hg were: 147.99, 6.13, and 3.42 µg kg^?1 in the tuna, kani, and salmon sushi samples, respectively, and 589.09, 85.09, and 11.38 µg kg^?1 in the tuna, octopus and salmon sashimi samples, respectively. The tuna samples showed the highest Hg concentrations. One portion of tuna sashimi exceeded the PTWI value for MeHg established for children and adults. The estimate of risk for human health indicated that the level of toxicity depended on the type of fish and size of the portion consumed.