计算机视觉技术对食品腐败检测的研究进展

食品腐败变质是食品安全问题中最主要的原因之一,据世界卫生组织(WHO)数据统计,每年全球食品工业仅因食品腐败变质带来的经济损失就多达数百亿美元。食品发生腐败变质不仅带来巨大的经济损失,而且给人们健康带来严重危害。食品在生产、加工、储存、运输和销售等各个环节中,当受到微生物、酶作用、机械损伤、病害、光照、氧气等不当的贮藏条件都有可能导致腐败变质。因此,加强对食品腐败变质的检测和监测显得尤为重要。然而,目前现有常用的检测方法存在过程操作繁琐、时效性差或灵敏度较低等缺点,难以满足现代快速准确检测的需要,成为制约食品质量安全的瓶颈。本文主要介绍了计算机视觉技术对微生物、病害引起的食品原料腐败变质的检测,来判断食品腐败变质的程度,并介绍最新进展及研究现状,最后展望了其应用前景。     

牛乳中微生物的微波致死特性实验研究

牛乳营养丰富,是微生物的优良培养基。而这些微生物却是造成牛乳腐败变质的主要原因。为了探讨牛乳中微生物的微波致死特性,本文进行了不同功率下的牛乳微波杀菌试验。通过实验表明,牛乳中的微生物在微波功率为600W时致死特性最显著,同时也表明随着微波功率的变大,微波致死时间呈双曲线型下降,而生产效率呈线性逐渐增加。     

低温肉制品加工、储运和销售过程中的微生物控制技术

微生物控制技术是保证低温肉制品的食用安全性和产品质量的关键技术。这是一个系统工程,要求从原辅料的品质,生产加工过程的技术参数、人员、器具、环境和管理各个环节进行质量控制;同时还要考虑产品的水活度,采取保鲜技术和保鲜剂,选择合适的包装并进行二次杀菌以达到控制产品微生物水平的目标;并保证在产品的储运和销售过程中进行冷链控制,为消费者提供具有较长保质期、安全性高的肉制品。     

贮藏时间和温度对生食粉品质影响的初探

本文研究了贮藏温度和时间对生食粉产品品质的影响,优化了最适贮藏条件。将生食粉分别置于20℃、40℃、60℃温度条件下,测定60d 内不同贮藏时间的感官指标、菌落总数、乳酸菌和大肠杆菌含量。结果表明,生食粉感官质量随着贮藏时间的延长而下降,菌落总数、乳酸菌和大肠杆菌含量在20℃、40℃条件下随贮藏时间的延长而增长,60℃条件下随贮藏时间的延长而下降。产品在20℃条件下贮藏可保持较好感官、卫生质量。     

Pulsed light for the inactivation of fungal biofilms of clinically important pathogenic Candida species

Microorganisms are naturally found as biofilm communities more than planktonic free‐floating cells; however, planktonic culture remains the current model for microbiological studies, such as disinfection techniques. The presence of fungal biofilms in the clinical setting has a negative impact on patient mortality, as Candida biofilms have proved to be resistant to biocides in numerous in vitro studies; however, there is limited information on the effect of pulsed light on sessile communities. Here we report on the use of pulsed UV light for the effective inactivation of clinically relevant Candida species. Fungal biofilms were grown by use of a CDC reactor on clinically relevant surfaces. Following a maximal 72 h formation period, the densely populated biofilms were exposed to pulsed light at varying fluences to determine biofilm sensitivity to pulsed‐light inactivation. The results were then compared to planktonic cell inactivation. High levels of inactivation of C. albicans and C. parapsilosis biofilms were achieved with pulsed light for both 48 and 72 h biofilm structures. The findings suggest that pulsed light has the potential to provide a means of surface decontamination, subsequently reducing the risk of infection to patients. The research described herein deals with an important aspect of disease prevention and public health.     

Changes of antibiotic resistance genes and gut microbiota after the ingestion of goat milk

Antibiotic resistance genes, as newly emerging contaminants, have become a serious challenge to public health through the food chain. The gut of humans and animals is an important reservoir for the development and dissemination of antibiotic resistance genes because of the great abundance and diversity of intestinal microbiota. In the present study, we evaluated the influence of goat milk on the diversity and abundance of antibiotic resistance genes and gut microbial communities, especially pathogenic bacteria. Male mice were used, 12 for each of the 2 groups: a control group that received sterile distilled water and a treated group that received goat milk, and gut microbiota and antibiotic resistance genes were compared in these groups using metagenomic analysis. The results revealed that ingestion of goat milk decreased the diversity and abundance of antibiotic resistance genes in the mice gut. The relative abundance of fluoroquinolone, peptide, macrolide, and β-lactam resistance genes in the total microbial genes significantly decreased after the intervention. Goat milk intake also significantly reduced the abundance of pathogenic bacteria, such as Clostridium bolteae, Clostridium symbiosum, Helicobacter cinaedi, and Helicobacter bilis. Therefore, goat milk intake might decrease the transfer potential of antibiotic resistance gene to pathogenic bacteria in the gut. In addition, bacteria with multiple resistance mechanisms accounted for approximately 4.5% of total microbial communities in the control group, whereas it was not detectable in the goat milk group, indicating the total inhibition by goat milk intake. This study highlights the influence of goat milk on antibiotic resistome and microbial communities in the gut, and provides a new insight into the function of goat milk for further study.     

微生物发酵稻草生产饲料工艺研究

利用稻草粉作为发酵基质,通过对培养基配方、培养基含水量、发酵温度及发酵周期的研究,探索到微生物发酵稻草生产饲料工艺条件为:稻草粉80 g、玉米粉19 g、尿素1 g、葡萄糖2 g、磷酸二氢钾0.1 g,培养基含水量为1∶2,发酵温度为30℃,发酵周期为6 d。产物分析结果表明:采用优化工艺进行发酵,发酵后稻草粉的纤维素含量为22.34%;粗蛋白含量达22.08%,可溶性糖含量为3.87%。     

杀菌技术的作用机制及在食品领域中的应用

杀菌是食品加工中保障食品安全的重要环节,高效杀菌同时又能最大限度保留食品原有的营养成分和色香味的杀菌技术成为食品科学领域的研究热点。该文综述了热杀菌技术、非热物理杀菌技术及化学杀菌技术的基本原理、特点及在食品表面与包装材料、果蔬肉类保鲜等领域应用研究进展,为杀菌技术在食品工业微生物污染控制与预防中的广泛应用提供参考,旨在提高食品的安全性和市场竞争力。     

酸马奶的微生物学及生产工艺研究现状

酸马奶作为一种传统的自然发酵乳制品,不仅含有丰富的微生物资源和生物活性成分,而且兼备营养价值和保健功效.文章结合近年来酸马奶研究取得的最新成果,系统综述了酸马奶的传统发酵工艺、微生物多样性、营养价值及保健功效等内容,并对酸马奶工业化生产的发展进行了分析,为解析酸马奶的微生物发酵机制和工业化生产提供参考.     

固定化酵母在使用过程中存在的问题

介绍在使用固定化酵母工艺中存在的易染菌、残糖高、使用周期短等问题.