对2005年度中国食品科学技术学会第四届年会论文的分析

对2005年度中国食品科学技术学会第四届年会论文征集情况作了简要的说明;分析了这些论文所涉及的研究领域与研究方向,从而揭示了我国当前食品及相关科学的研究现状与发展趋势。     

谈《食品卫生法》中行政管理相对人的法律义务和法律责任的对等问题

运用法学理论，阐述法律义务和法律责任对等的涵义和必要性，分析了《食品卫生法》中行政管理相对人在两者之间的不对等现象并提出了相应建议。     

Past,present and future activities in food hygiene of the Veterinary Public Health Unit (VPH) of the World Health Organization

The paper contains a review of the activities in the field of food hygiene performed by the Veterinary Public Health Unit of WHO in close collaboration with other divisions and programmes of the Organization. It gives a general understanding about the purpose and objectives of such activities in the past and present, and near future. The paper mentions the most important achievements which were reached by the Organization in meat and milk hygiene, fish and shellfish hygiene, surveillance of foodborne diseases, microbiological specifications for foods, food virology education and training in food hygiene and elaboration of a strategy on prevention and control of foodborne diseases due to food of animal origin. The paper contains 44 references, the majority of which are still available at the World Health Organization.     

纵横正有凌云笔(一)--"芯"中的网版印刷技术

介绍了集成电路高精密度的电子封装技术中的网版印刷技术．对当今最先进的电子封装芯HCSP、UBGA等制造枝术中的网版印刷工艺作了较为详细的述评；强调了创新是网版印刷控水在电子封装工程中克难制胜的法宝。     

Gas chromatographic evaluation of amino acid epimerisation in the course of gelatin manufacturing and processing

 Using capillary gas chromatography on chiral stationary phases total hydrolysates of gelatins were investigated for their amounts of D-amino acids (D-AAs). Gelatins of different quality and origin were analysed including gelatin-containing final products like candies and meat products. In gelatins manufactured by stepwise extraction (first to fifth extract) with water of increasing temperature (ca. 55–95°C) amounts of 2.7–4.8% of D-aspartic acid (D-Asp) were determined in extracts obtained at ≤ 85°C. The amounts D-Asp were as high as 28.1% in fifth extracts obtained at 95°C (data corrected for 4.3% of D-Asp determined in native collagen as a result of acid-induced epimerisation of L-Asp during total hydrolysis). Epimerisation of aspartyl or asparaginyl residues of proteins in general on heating in water is assumed to proceed via formation of aspartyl succinimide, tautomerisation and release of D-Asp on total hydrolysis. The other AA residues of gelatin showed only a slight increase of epimerisation with increasing thermal treatment. Furthermore, amounts of 3–4% of cis-4-D-hydroxyproline, formed from native trans-4-L-hydroxyproline in collagen on hydrolysis, were detected in total hydrolysates of all gelatins. Received: 8 August 1997 / Revised version: 24 November 1997     

转基因食品的安全性评价

转基因食品的安全性一直受到各国政府、科学工作者及广大消费者的重视如何科学地评价该类食品的安全性,FAO/WHO等国际组织提出了一些政策性建议本文就转基因食品安全性评价的发展、评价原则、安全性要求、评价方法等作综述     

Comparison of three methods for detection of herbal food supplement irradiation

A survey for irradiation of 106 herbal food supplements was carried out in Denmark in 2003. The results from three methods, two screening methods and a specific method, were compared: Direct epifluorescent filter technique/aerobic plate count (DEFT/APC), photostimulated luminescence (PSL) and thermoluminescence (TL) standardised by Comité Européen de Normalisation (CEN). Forty samples screened positive with the DEFT/APC method. However, the TL method could only confirm irradiation of 15 samples, 11 samples wholly irradiated and 4 samples with a minor irradiated ingredient. Thus, the DEFT/APC method gave a large number of false positive results, although the number of false negative results probably was very low. Only 7 of the 15 confirmed irradiated samples screened positive with the PSL screening method, the samples with low photon counts escaping detection. For 10% of the samples also the TL method was lacking in sensitivity, as not enough minerals could be isolated to get a signal over the minimum detection level. For such clean herbal food supplements no suitable method exists at all among the CEN standardised methods for irradiation detection.     

Acrylamide levels in Finnish foodstuffs analysed with liquid chromatography tandem mass spectrometry

Sample clean-up and HPLC with tandem mass spectrometric detection (LC-MS/MS) was validated for the routine analysis of acrylamide in various foodstuffs. The method used proved to be reliable and the detection limit for routine monitoring was sensitive enough for foods and drinks (38 microg/kg for foods and 5 microg/L for drinks). The RSDs for repeatability and day-to-day variation were below 15% in all food matrices. Two hundred and one samples which included more than 30 different types of food and foods manufactured and prepared in various ways were analysed. The main types of food analysed were potato and cereal-based foods, processed foods (pizza, minced beef meat, meat balls, chicken nuggets, potato-ham casserole and fried bacon) and coffee. Acrylamide was detected at levels, ranging from nondetectable to 1480 microg/kg level in solid food, with crisp bread exhibiting the highest levels. In drinks, the highest value (29 microg/L) was found in regular coffee drinks.     

浅谈减少塑料包装对环境污染的几条途径

由于塑料包装材料对环境的污染越来越严重，对人类的生活已造成了很大的影响。本文经归纳整理，从以下三个方面探讨了如何减少塑料包装材料对环境的污染：1、塑料包装循环再用，2、发展绿色包装──环保包装，3、提高全民思想素质。     

Ammonia gas permeability of meat packaging materials

Meat products are packaged in polymer films designed to protect the product from exterior contaminants such as light, humidity, and harmful chemicals. Unfortunately, there is almost no data on ammonia permeability of packaging films. We investigated ammonia permeability of common meat packaging films: low-density polyethylene (LDPE; 2.2 mil), multilayer polyolefin (MLP; 3 mil), and vacuum (V-PA/PE; 3 mil, 0.6 mil polyamide/2.4 mil polyethylene). The films were fabricated into 10 × 5 cm pouches and filled with 50 mL deionized water. Pouches were placed in a plexiglass enclosure in a freezer and exposed to 50, 100, 250, or 500 ppm ammonia gas for 6, 12, 24, and 48 h at -17 ± 3 °C and 21 ± 3 °C. At freezing temperatures, no ammonia residues were detected and no differences in pH were found in the water. At room temperature, ammonia levels and pH of the water increased significantly (P < 0.05) with increasing exposure times and ammonia concentrations. Average ammonia levels in the water were 7.77 ppm for MLP, 5.94 ppm for LDPE, and 0.89 ppm for V-PA/PE at 500 ppm exposure for 48 h at 21 ± 3 °C. Average pH values were 8.64 for MLP, 8.38 for LDPE, and 7.23 for V-PA/PE (unexposed ranged from 5.49 to 6.44) at 500 ppm exposure for 48 h. The results showed that temperature influenced ammonia permeability. Meat packaging materials have low ammonia permeability and protect meat products exposed to ammonia leaks during frozen storage.