Consumption patterns,bacteriological quality and risk factors for Salmonella contamination in meat-based meals consumed outside the home in Kigali,Rwanda

Meat-based meals are consumed as a source of animal proteins and constitute one of the leading vehicles for food borne infections in humans. The main objective of this study was to determine the consumption pattern and the bacteriological quality of meat-based meals consumed outside households in Kigali. A survey on meat consumption patterns was carried out in 400 households by using a questionnaire, whereas different meat-based meals were sampled from 150 snack bars and restaurants. Enumeration of hygiene indicator bacteria (total mesophilic bacteria and Escherichia coli) and the qualitative detection of Salmonella were carried out by using conventional culture methods. The results indicated that goat was the type of meat that was consumed the most outside the home in Kigali and the meat intake varied significantly (p ≤ 0.05) with the social category of the household. The average levels of total aerobic bacteria and E. coli in meat-based meals were found to be 4.7 and 1.4 log cfu/g, respectively, whereas Salmonella was detected in 11.7% of all meat-based meals. Eight factors mostly linked to the cooking treatments and hygienic handling practices for cooked meals were found to be significantly (p ≤ 0.05) associated with the risk of Salmonella occurrence in meat-based meals consumed outside the home in Kigali. The findings from this study strongly suggest the need for proper cooking and/or improvements in hygiene in the establishments selling ready-to-eat meat-based meals in Kigali, particularly those located in rural localities.     

Effects of feeding an aquatic weed Lemna trisulaca as partial replacement of fish meal on the performance of growing ducklings

Growing ducklings were fed diets containing an aquatic weed Lemna trisulaca meal (LTM) replacing, on a protein basis, either 40, 60 or 80 g kg^?1 of the fish meal (FM) from a control diet which contained 120 g FM kg^?1. Partial replacement of FM (40 and 60 g kg^?1 of the FM) by LTM on a protein basis showed good growth and low food consumption but food conversion efficiency was found to be comparable. It was concluded that LTM could be considered as a protein feed supplement for growing ducklings and also as a part replacement of animal protein (FM) in the nutrition of growing ducklings without deleterious effect on performance.     

Heat and Moisture Transfer in Composite Food—Theoretical Analysis of Influence of Surface Conductance and Component Arrangement

Heat and moisture transfer in composite bodies undergoing drying was simulated using a previously developed mathematical model which included the chemical potential of moisture as a mass transfer potential. Composite bodies included layered cylinders and concentric spheres consisting of a starch granule hydrate (H) and a hydrate of starch granules-sucrose 3:l mixture (S). The influence of the following factors on heat and moisture transfer was examined: convective surface mass transfer conductance, initial moisture, and component arrangement. The three factors significantly influenced moisture transfer white they had slight influence on heat transfer. Overall drying rate of each composite body was infhrenced interactively by moisture fluxes, which were caused by a surrounding drying medium and by a mass transfer potential difference across the interface of H and S.     

The polymerase chain reaction: Applications for the detection of foodborne pathogens

Faster methods for the detection of foodborne microbial pathogens are needed. The polymerase chain reaction (PCR) can amplify specific segments of DNA and is used to detect and identify bacterial genes responsible for causing diseases in humans. The major features and requirements for the PCR are described along with a number of important variations. A considerable number of PCR‐based assays have been developed, but they have been applied most often to clinical and environmental samples and more rarely for the detection of foodborne microorganisms. Much of the difficulty in implementing PCR for the analysis of food samples lies in the problems encountered during the preparation of template DNAs from food matrices; a variety of approaches and considerations are examined. PCR methods developed for the detection and identification of particular bacteria, viruses, and parasites found in foods are described and discussed, and the major features of these reactions are summarized.     

保健食品中人参皂甙的测定方法

人参系五加科植物人参PanaxginsengCAMeyer的根。含有多种人参皂甙(panaxsaponin),系三萜皂甙。多数为达玛烷型皂甙,如人参皂甙Ra1、Ra2、Rb1、Rb2、Rb3、Rc、Rd等;少数为齐墩果酸型(C型)皂甙,如人参皂甙Ro。由于甙元不同,达玛烷型皂甙又分为20S-原人参二醇类皂甙(A型)和20S-原人参三醇类皂甙(B型)。其中A型和B型皂甙酸水解后,分别得到人参二醇(panaxadial)和人参三醇(panaxatriol)。本文报导用大孔树脂吸附样品中人参皂甙,先用水洗去糖分,再应用稀乙醇洗下人参皂甙,再用香草醛与人参皂甙反应显色而进行比色。     

美国食品所标示的有关膳食脂肪与冠心病关系的健康声明及对中国出口食品的指导意义

介绍了ＦＤＡ关于食品健康声明的定义,膳食脂肪与冠心病关系,可以标示健康声明的食品要求以及ＦＤＡ在最终通过健康声明之前须考虑的安全性问题,为国内的食品界提供一些参考信息。     

番茄黄瓜菜汁豆腐加工工艺

以番茄汁、黄瓜汁和大豆为原料研制了色泽美观的天然、营养豆腐,丰富了豆腐的品种,有良好的发展前景。     

Physical polymer surface modification methods and applications in food packaging polymers.

Continued innovations in the polymer industry have made polymer surface modification methods a subject of intense research. The importance and necessity of surface modification of plastics are explained, and the advantages of physical surface treatments over the less-sophisticated chemical methods are outlined. Currently available physical surface modification methods for food packaging polymers are reviewed from the food packaging perspective. These physical surface modification methods include flame, corona discharge, UV, gamma-ray, electron beam, ion beam, plasma, and laser treatments. The principle of operation of each method is briefly described, and the advantages and disadvantages of each technique are cited. The extent to which each of these methods can produce the specific modifications desired is discussed. Furthermore, the effects of each treatment on barrier, mechanical, and adhesion properties of food packaging polymers are also examined. Finally, an overview of economic aspects of sophisticated surface modification techniques, including ion beam, plasma, and laser treatments, is presented.     

Prevention of Clostridium botulinum Type A, Proteolytic B and E Toxin Formation in Refrigerated Pea Soup by Lactobacillus plantarum ATCC 8014

The ability of Lactobacillus plantarum ATCC 8014 to inhibit Clostridium botulinum toxin production in pea soup was investigated. Soup containing C. botulinum spores (10³/g) with and without L. plantarum (10⁶/g) were evaluated. Soup containing only type A spores was toxic on days 1 and 2 when incubated at 35°C and 25°C, respectively. Soup containing only proteolytic type B spores was toxic on days 2 and 5 at 35°C and 25°C, respectively. Soup containing only type E spores was toxic at 25°C, 15°C, and 5°C in 7, 7, and 63 days respectively. No toxin was found in soup containing C. botulinum spores plus L. plantarum at any temperature studied.     

基于移动平台的食品分拣机械手设计

提出了一种基于移动平台的食品分拣机械手,给出其设计指标、机械以及控制系统结构,对其工作空间进行了仿真计算,并对该机械手的末端定位精度进行了实验研究,结果表明基于移动平台的食品分拣机械手设计合理,可以有效地完成精确操作。