Properties of Bacillus cereus and other bacilli contaminating biomaterial-based industrial processes

This paper is an overview on bacilli in industrial processes, with focus on food grade paper and paperboard production. Paperboards mainly contain sporeforming bacteria belonging to the genera Bacillus, Paenibacillus and Brevibacillus, usually found in quantities from <50 to 250 cfu g⁻¹ homogenized paperboard. Of those frequently found, Bacillus cereus group, B. licheniformis, B. subtilis and Brevibacillus brevis are important for food hygiene because of their hydrolytic activities on food components and the ability of some strains to produce food poisoning toxins or to grow at refrigerated temperatures. We found that the phenotypic properties (lecithinase activity, nitrate reduction) used in standard methods (e.g., ISO, FDA, IDF) to recognize B. cereus, were unreliable for industrial isolates. Whole cell fatty acid composition of a group of the industrial isolates deviated so much from those in a widely used commercial database that the strains were not or only poorly recognized as B. cereus. Industrial isolates, including toxigenic ones, often missed one or more of these characters, even in cases where 100% 16S rDNA identity was found with B. cereus or with B. thuringiensis. 11-Methyldodecanoic acid and trans-9-hexadecenoic acid were found without exception in over 200 industrial B. cereus group isolates and in over 30 culture collection strains. The detection of these fatty acids is a secure method for the identification of B. cereus. Negative reaction for starch hydrolysis and for BCET-RPLA test and a specific ribotype were found in all B. cereus strains producing the emetic toxin.     

250t/d液化装置工程设计

简单介绍了 2 5 0t/d液化装置项目的设计参数和主要设备情况 ;结合 2 5 0t/d液化装置的工艺设备平面布置、管道布置及职业安全卫生要求 ,提出了空分气体液化装置工程设计中应注意的问题。     

HACCP系统在冷菜加工中的应用

餐饮卫生安全的控制是减少食物中毒发生的关键,是餐饮业控制的要点.在餐饮业冷菜加工中建立有效的危害分析与关键点控制(HACCP)系统,对冷菜加工中可能出现的危害进行具体分析,并确定关键控制点与控制措施,这样能确保冷菜食品的安全性,减少食物中毒的发生.     

Influence of free-stall base on tarsal joint lesions and hygiene in dairy cows

The objective was to quantify the incidence of tarsal lesions and level of hygiene by stall bed type. Cows were scored on 100 dairies from Wisconsin, Minnesota, Indiana, Iowa, and New York in the fall and winter. Thirty-eight dairies used rubber-filled mattresses (RFM), 27 had sand beds, 29 had waterbeds, and 6 used compost packs (CPk). Stocking density, stall dimensions, bedding amount, bedding frequency, and type of bedding were recorded. One pen of early-lactation multiparous cows on each dairy was scored based on injury of the tarsal joints at the lateral and medial surfaces and tuber calcis at the dorsal, lateral, and medial surfaces. A tarsal score of 1 represented hair loss, 2 was moderate, and 3 indicated severe swelling. Differences between bed types in the percentages of cows with lesions were tested with one-way ANOVA by lesion severity and incidence, with farm as the experimental unit. Cows on sand beds or waterbeds had fewer lesion scores of 1, 2, and 3 than those on RFM. The percentages of score 1 were 54.6 ± 4.4 (RFM), 22.5 ± 4.7 (sand), and 29.8 ± 4.3 (waterbed), whereas the percentages of score 2 were 14.0 ± 1.4, 2.3 ± 1.5, and 5.0 ± 1.4, and of score 3 were 3.0 ± 0.4, 0.2 ± 0.4, and 0.4 ± 0.4. Cows on CPk had no lesions. Hygiene scores ranged from 1 to 5, with 1 being clean and 5 soiled. The percentages of hygiene score 1 were 0 (compost), 0.4 (RFM), 0.4 (sand), and 0.4 (waterbeds); those with score 2 were 79.0, 84.0 ± 0.01, 73.2 ± 0.01, and 80.4 ± 0.01; with score 3 were 20.3, 15.2 ± 0.01, 23.8 ± 0.01, and 18.6 ± 0.01; with score 4 were 0.8, 0.005 ± 0.001, 0.006 ± 0.001, and 0.025 ± 0.003; and with score 5 was 0 for all bed types. Cows on RFM and waterbeds had improved hygiene compared with cows on sand beds. There was no difference in somatic cell count (SCC) by bed type. The percentage of cows in fourth lactation or greater on waterbeds (19.8 ± 1.8) was greater than those on RFM (13.3 ± 1.6) or on sand (13.5 ± 1.8). The percentage culled was lower for cows on waterbeds than on RFM (22.8 ± 1.5 vs. 29.4 ± 1.4). Score 3 tarsal lesions were correlated (r = 0.60) with SCC. The length of the sand bed was correlated with a greater percentage of mature cows. The SCC was correlated with the percentage of cows reported lame on the day of the visit (r = 0.45) and with neck rail height (r = −0.26). On dairies with RFM, severe lesions (r = 0.60), death losses (r = 0.52), and percentage of the herd reported lame on the day of the visit (r = 0.52) were all correlated with the SCC. Dairies with higher percentages of lesions had higher SCC, death losses, lameness, and culling rates. Adding bedding several times per week may reduce the incidence of lesions.     

2017年广州市网络订餐餐饮食品卫生情况调查

目的 了解广州市网络订餐餐饮食品的卫生状态, 排查风险隐患。方法 通过网络订餐服务平台, 对广州6个中心城区近年网络订餐消费量大、人气高的网络订餐餐饮服务单位进行抽样, 依据DBS 44/006-2016《非预包装即食食品微生物限量》标准进行检验和判定。结果 抽检5大类500份样品, 合格451份, 总体合格率为90.20%, 不合格项目主要是菌落总数和大肠埃希氏菌2个卫生指标菌。500份样品中共检出14株食源性致病菌, 其中金黄色葡萄球菌检出9株, 蜡样芽胞杆菌检出5株, 沙门氏菌、副溶血性弧菌、单核细胞增生李斯特氏菌、大肠埃希氏菌O157均未检出。连锁餐饮服务单位的合格率较高, 非连锁餐饮服务单位的小型餐饮合格率最低。结论 广州市网络订餐餐饮食品总体卫生情况主要体现在卫生指标菌不合格, 食源性致病菌符合标准。熟肉制品、米面及其制品(米饭、米粉、肠粉、面条、粥、饺子等)、熟制凉拌菜与寿司等这3类食品比较容易受到微生物污染, 需引起监管重视。     

2014~2016年保山市农村饮用水卫生状况监测分析

目的 调查保山市农村地区饮用水水质现状, 为改善保山市农村饮水水质卫生状况、预防介水传染病提供科学依据。方法 采集农村集中式供水水样1404份, 水样按照《生活饮用水标准检验方法》(GB/T 5750-2006)进行感官性状和一般化学指标、毒理学指标、微生物指标等31个指标的检验, 按照《生活饮用水卫生标准》(GB 5749-2006)进行评价。采用χ2检验进行率的比较分析。结果 2014~2016年共检测农村地区饮用水1404份, 合格521份, 合格率为37.11%, 其中微生物指标合格率最低(46.72%); 水样合格率随年份增加而升高(χ2=120.174, P<0.001)。感官性状和一般化学指标合格率枯水期(74.36%)高于丰水期(66.81%), 有统计学差异(χ2=9.636, P=0.002); 微生物指标合格率丰水期(52.14%)高于枯水期(41.31%), 有统计学差异(χ2=16.527, P<0.001); 水样合格率常规处理(包含混凝、沉淀、过滤、消毒)>仅消毒>未处理>沉淀/过滤(χ2=264.479, P<0.001); 水样合格率随供水能力的增加而增加(χ2=8.420, P=0.004)。结论 保山市农村地区饮用水水质合格率低, 微生物指标是影响保山市农村地区饮用水安全的主要因素, 水期类型、供水方式、水样类型、供水能力是水质卫生状况的影响因素。为保证该市农村地区饮用水的卫生、安全, 有关部门亟待采取有效的措施, 提高农村地区水质, 保护人民群众的健康。     

对于我国当前肉品卫生管理的几点建议

本文针对国家某些肉品卫生规程的统一性和时效性以及监管人员的业务素质问题,提出了一些建议.     

Trapping the food safety performance of a small or medium-sized food company using a risk-based model. The HYGRAM system

The requirements of implementing Hazard Analysis and Critical Control Points (HACCP) principles in food production are increasing. A practical risk quantification model, HYGRAM, was developed for small and medium-sized enterprises to meet this challenge. The model makes the user familiar with the HACCP principles by software-assisted guidance through the procedure, connecting special microbiological hazards, good hygiene practice, and other prerequisite programs to HACCP. HYGRAM is a tool to analyze and quantify risks of different processes, and to compare them. It is developed to relieve enterprises with limited resources in confirming the food safety of their production.     

复杂底纹柔性卫生用品表面缺陷检测算法研究

目的 柔性卫生用品由于其材料表面不平整、产品容易发生变形等特性,给机器视觉中图像关键区域的定位和分割带来了很大问题,从而影响检测结果。为了解决复杂底纹柔性卫生用品表面脏点的检测问题,提出一种新型检测算法,以实现对复杂底纹柔性卫生用品快速又精准的检测。方法 在该检测算法中首先对采集的模板图像和样本图像进行预处理,在模板图像中创建一个合适特征模板,根据特征模板进行样本图像的匹配和定位;然后把经过精准定位后的样本图像进行关键区域分割;最后运用差影法把样本关键区域中的缺陷找出。该算法采用德国MVtec公司的halcon算子加以编程实现。结果 实验结果显示,该算法能够识别棉芯表面大于0.04 mm2的脏点,检测1幅图片的平均时间平均在100 ms,检测准确率为100%。结论 文中方法与传统方法相比,鲁棒性强,速度快,能够满足工业高速生产的需求。     

我国非织造布专用化纤的发展前景

本文对卫生材料、高蓬松性产品、针刺地毯与土工布等主要非织造布产品及其化纤原料的发展方向进行了讨论 ,指出了各自的发展前景与应采取的措施