A review on novel non-thermal food processing techniques for mycotoxin reduction

The overarching challenges of mycotoxin contamination in food necessitate the development of strategies to be implemented to combat their effects thereof. Common processing techniques have been utilised but do not necessarily meet the desired efficacy. This review appraises studies on novel non-thermal food processing techniques, particularly high pressure processing, pulsed electric filed, cold plasma and ultrasound processing for the decontamination of mycotoxins in food. Although available studies on these techniques have suggested a reduction of mycotoxins and in some instances, complete decontamination of mycotoxins was also reported. The mechanisms by which reduction/elimination occurs include through decomposition of toxins after collision with ions/electrons leading to cleavage of bonds, structural degradation of the mycotoxins structure and cleavage of functional groups. Additional studies into the toxicity of degraded products and the composition of the food products are still required to ensure a more widespread adoption of these techniques to enhance food safety.     

茶叶中真菌与真菌毒素污染风险状况与防控研究进展

茶叶因具有独特的风味以及对人体有益的生物活性物质,深受国内外消费者青睐。茶叶作为生产链较长的特殊经济农作物,其在生产过程中涉及的微生物背景仍不清晰,存在着潜在的有害微生物及真菌毒素污染。目前调查显示饮茶导致的真菌毒素暴露风险极低,但茶叶中真菌及真菌毒素污染的监控以及相关有害次级代谢产物的溯源问题亟待解决。本文综述了国内外有关茶叶中真菌及真菌毒素污染状况与防控相关研究,分析探讨了茶叶中真菌毒素的潜在污染风险,以期为茶叶中真菌毒素污染评估和防控提供参考依据,促进茶叶良好的质量管理和卫生控制体系的建立。     

食品中新兴真菌毒素检测技术及其污染现状研究进展

真菌毒素是由曲霉菌、青霉菌和镰刀菌等丝状真菌在适当的环境条件下产生的有毒次生代谢产物，是谷物、水果、坚果等食品中常见的污染物，可引起广泛的毒性效应，主要表现为致癌性、致突变性、肝毒性、肾毒性、免疫毒性、神经毒性、致畸性等，对人类和动物的健康构成威胁。近些年来，由于自然气候的改变及检测技术的创新发展，一些新出现的真菌毒素逐渐引起大家的广泛关注，如已报道的交链孢毒素、新兴镰刀菌毒素等。这些尚未得到监管，并且如何产生、浓度水平和毒理数据有限的真菌毒素被定义为“新兴”真菌毒素。本文综述了两大类12种新兴毒素的结构性质、检测分析技术进展及在食品中的污染状况，以期为真菌毒素污染的全面评估及防控提供思路。     

2016—2020年上海市市售即食食品微生物污染状况分析及评价

目的 了解上海市市售即食食品中微生物污染情况,及时发现食品安全隐患,为即食食品风险评估、管理和标准制定提供科学依据。方法 2016-2020 年共采集上海市即食食品20类共10 521份食品样品,对菌落总数、大肠埃希氏菌计数2种卫生指示菌和副溶血性弧菌、金黄色葡萄球菌、致泻大肠埃希氏菌、沙门氏菌、蜡样芽孢杆菌、单核细胞增生李斯特氏菌（以下简称单增李斯特菌）6种食源性致病菌进行定量或定性检验,并分析卫生指示菌和食源性致病菌污染水平及关联性。结果 凉拌米面制品、沙拉、中式凉拌菜的指示菌污染水平较高,菌落总数均值分别为（5.13±1.43）lgCFU/g、（4.56±1.13）lgCFU/g、（4.26±1.75）lgCFU/g;大肠埃希氏菌计数分别为（1.20±1.00）lgCFU/g、（1.47±1.41）lgCFU/g、（1.18±1.06）lgCFU/g。冷锅串串、沙拉、中式凉拌菜、熟肉制品中单增李斯特菌检出率较高,分别为6.27%、3.36%、2.71%、2.69%;副溶血性弧菌仅在生食动物性水产品（3.65%）、中式凉拌菜（2.58%）、熟肉制品（0.42%）中检出;米面制品中蜡样芽孢杆菌（7.51%）显著高于寿司（0.53%）（P<0.05）。菌落总数均值与大肠埃希氏菌计数均值呈极显著正相关（P<0.001）;菌落总数均值与致病菌样品阳性率呈显著正相关（P<0.05）。结论 上海市生食食物、凉拌、夹心等最后一步加工工艺非加热的即食食品,卫生指示菌和致病菌污染水平较高,食源性致病风险较高,应重点防范。固体即食食品菌落总数计数水平与食源性致病菌污染状况存在相关性。     

天然醛类化合物在农产品采后真菌病害防治中的应用进展

农产品种类众多、营养价值丰富,在人类日常饮食中不可或缺。然而,水果、蔬菜、食用菌和甘薯等农产品在采后易受病原真菌感染而发生腐烂变质,导致品质下降,贮藏期缩短。目前,主要通过化学杀菌剂来控制农产品采后腐烂,但化学杀菌剂的长期重复使用会导致病原菌抗药性增加、农药残留及环境污染等问题。天然醛类化合物具有广谱杀菌作用,尤其是针对农产品采后真菌病害的防治,具有绿色安全、快速有效等优点,在农产品保鲜中具有巨大的应用潜力。本文综述了天然醛类化合物的化学组成,对农产品采后病原真菌的抑制活性与抑菌机制,以及在农产品采后真菌病害防治中应用的研究进展,并对其在农产品采后保鲜中应用的未来趋势进行展望,以期为天然醛类化合物在农产品保鲜中更深层次的应用提供理论依据和新思路。     

Multimycotoxin and fungal analysis of maize grains from south and southwestern Ethiopia

The natural occurrence of fungi, mycotoxins and fungal metabolites was investigated in 100 samples of maize grains collected from south and southwestern Ethiopia in 2015. The maize samples were contaminated by Fusarium, Aspergillus and Penicillium species. Using liquid chromatography tandem mass spectrometry 127 secondary metabolites were analysed. Zearalenone was the most prevalent mycotoxin, occurring in about 96% of the samples. Zearalenone sulfate was the second most prevalent, present in 81% of the samples. Fumonisin B1 was detected in 70% of the samples with a mean level of 606 μg kg^?1 in positive samples, while FB2, FB3 and FB4 were detected in 62%, 51% and 60% of the maize samples with mean levels of 202, 136 and 85 μg kg^?1, respectively. Up to 8% of the samples were contaminated with aflatoxins, with a maximum level of aflatoxin B1 of 513 μg kg^?1. Results were higher than earlier reports for maize from Ethiopia.     

Invited review: Controlling dairy product spoilage to reduce food loss and waste

Food loss and waste is a major concern in the United States and globally, with dairy foods representing one of the top categories of food lost and wasted. Estimates indicate that in the United States, approximately a quarter of dairy products are lost at the production level or wasted at the retail or consumer level annually. Premature microbial spoilage of dairy products, including fluid milk, cheese, and cultured products, is a primary contributor to dairy food waste. Microbial contamination may occur at various points throughout the production and processing continuum and includes organisms such as gram-negative bacteria (e.g., Pseudomonas), gram-positive bacteria (e.g., Paenibacillus), and a wide range of fungal organisms. These organisms grow at refrigerated storage temperatures, often rapidly, and create various degradative enzymes that result in off-odors, flavors, and body defects (e.g., coagulation), rendering them inedible. Reducing premature dairy food spoilage will in turn reduce waste throughout the dairy continuum. Strategies to reduce premature spoilage include reducing raw material contamination on-farm, physically removing microbial contaminants, employing biocontrol agents to reduce outgrowth of microbial contaminants, tracking and eliminating microbial contaminants using advanced molecular microbiological techniques, and others. This review will address the primary microbial causes of premature dairy product spoilage and methods of controlling this spoilage to reduce loss and waste in dairy products.     

茶叶中产毒真菌污染现状及其生物防控研究进展

茶是世界上三大饮品之一, 其饮用安全性对于消费者健康以及茶产业发展尤为重要。产毒真菌在自然界中分布广泛, 茶叶在生长、采摘、加工、运输以及仓储过程中存在潜在的真菌污染。真菌毒素是真菌代谢产生的一类有毒次级代谢产物, 会在茶叶基质中积累, 不仅给人类健康造成严重威胁, 也给全球经济带来巨大损失。我国是茶叶生产和出口大国, 随着国际贸易壁垒的日益森严, 进口国对茶叶中残留的微生物和真菌毒素检测愈加严格。此外, 检测茶叶中真菌及真菌毒素对于茶叶安全、茶叶仓储及相关行业标准具有一定的指导意义。本文综述了国内外红茶、黑茶、绿茶、白茶、青茶和黄茶中产毒真菌污染现状及生物防控的研究进展, 并就今后防范措施提出建议, 以期为茶叶中真菌及其真菌毒素安全控制提供参考, 促进茶产业健康可持续发展。     

Strategies to prevent mycotoxin contamination of food and animal feed: a review

Mycotoxins are fungal secondary metabolites that have been associated with severe toxic effects to vertebrates produced by many important phytopathogenic and food spoilage fungi including Aspergillus, Penicillium, Fusarium, and Alternaria species. The contamination of foods and animal feeds with mycotoxins is a worldwide problem. We reviewed various control strategies to prevent the growth of mycotoxigenic fungi as well as to inhibit mycotoxin biosynthesis including pre-harvest (resistance varieties, field management and the use of biological and chemical agents), harvest management, and post-harvest (improving of drying and storage conditions, the use of natural and chemical agents, and irradiation) applications. While much work in this area has been performed on the most economically important mycotoxins, aflatoxin B(1) and ochratoxin A much less information is available on other mycotoxins such as trichothecenes, fumonisin B(1), zearalenone, citrinin, and patulin. In addition, physical, chemical, and biological detoxification methods used to prevent exposure to the toxic and carcinogenic effect of mycotoxins are discussed. Finally, dietary strategies, which are one of the most recent approaches to counteract the mycotoxin problem with special emphasis on in vivo and in vitro efficacy of several of binding agents (activated carbons, hydrated sodium calcium aluminosilicate, bentonite, zeolites, and lactic acid bacteria) have also been reviewed.     

坚果及籽类食品中霉菌与真菌毒素防控技术研究进展

坚果及籽类食品富含蛋白质、脂肪酸等多种营养素,深受消费者喜爱。然而这类食品易被霉菌及其产生的真菌毒素污染,危害人体健康。本文综述了国内外坚果及籽类食品中霉菌与真菌毒素防控技术的研究进展,旨在为坚果及籽类食品的安全生产和有效监管提供科学依据。     

A survey of the fungal contamination and presence of ochratoxin A and zearalenone on Spanish feed and raw materials

The incidence of fungal contamination in 91 samples of feed and raw materials used for animal feeding in Spain has been studied. Sample analysis was accomplished in a new culture medium to which a beta‐cyclodextrin had been added, and a comparison with other more usual culture media was performed. Ochratoxin A (OTA) and zearalenone (ZEA) contamination of all the samples was evaluated by RP‐HPLC with fluorescence detection. The fungal genera found, such as Penicillium and Fusarium, included mycotoxigenic strains as OTA and ZEA (33.3 and 26.4% incidence respectively). One sample of corn and another of cotton seed were contaminated with levels of OTA above the 5 and/or 10 µg kg^?1 recommended by the legislation of several European countries, whereas none of the samples contaminated with ZEA surpassed the legislation limits suggested by the official agencies. Copyright © 2004 Society of Chemical Industry     

Worldwide aflatoxin contamination of agricultural products and foods: From occurrence to control

Aflatoxins represent a global public health and economic concern as they are responsible for significant adverse health and economic issues affecting consumers and farmers worldwide. Produced by fungal species from the Aspergillus genus, aflatoxins are a toxic, mutagenic, and carcinogenic group of fungal metabolites that routinely contaminate food and agricultural products. Climate and diet are essential factors in the aflatoxin contamination of food and subsequent human exposure process. Countri es with warmer climates and staple foods that are aflatoxin-susceptible shoulder a substantial portion of the global aflatoxins burden. Enactment of regulations, prevention of pre- and postharvest contamination, decontamination, and detoxification have been used to prevent human dietary exposure to aflatoxin. Exploiting their chemical and structural properties, means are devised to detect and quantify aflatoxin presence in foods. Herein, recent developments in several important aspects impacting aflatoxin contamination of the food supply, including: fungal producers of the toxin, occurrence in food, worldwide regulations, detection methods, preventive strategies, and removal and degradation methods were reviewed and presented. In conclusion, aflatoxin continues to be a major food safety problem, especially in developing countries where regulatory limits do not exist or are not adequately enforced. Finally, knowledge gaps and current challenges in each discussed aspect were identified, and new solutions were proposed.     

Consumer preferences and fungal and mycotoxin contamination of dried cassava products from Ghana

Summary Members of one hundred and twenty five households from 19 villages producing dried cassava products were interviewed in Ghana. Kokonte was the most important cassava product in 19% of the households processing it. Most kokonte was produced between January and March. Mould growth during processing or storage was a problem during June and July, which is part of the rainy season. Most producers and market traders preferred non-mouldy kokonte, although many (59%) would consume a mouldy product. There was a price premium for non-mouldy kokonte. The most commonly isolated fungi were yeasts and Cladosporium spp. (44 out of 49 samples). Other fungi isolated included Aspergillus spp. (20 samples); Penicillium spp. (15 samples) and Fusarium spp. (30 samples). Sterigmatocystin was detected in 10 samples at 0.17–1.67 mg kg^–1; patulin in 4 samples at 0.55–0.85 mg kg^–1; cyclopiazonic acid in 4 samples at 0.08–0.72 mg kg^–1; penicillic acid in 5 samples at 0.06–0.23 mg kg^–1 and tenuazonic acid in 3 samples at 0.02–0.34 mg kg^–1. Mycotoxin contamination of mouldy kokonte was a potential problem; there is therefore the need to improve kokonte processing to avoid mould growth.     

Switchgrass extractives to mitigate Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium contamination of romaine lettuce at pre- and postharvest

The antimicrobial potential of switchgrass extractives (SE) was evaluated on cut lettuce leaves and romaine lettuce in planta, using rifampicin-resistant Escherichia coli O157:H7 and Salmonella Typhimurium strain LT2 as model pathogens. Cut lettuce leaves were swabbed with E. coli O157:H7 or S. Typhimurium followed by surface treatment with 0.8% SE, 0.6% sodium hypochlorite, or water for 1 to 45 min. For in planta studies, SE was swabbed on demarcated leaf surfaces either prior to or after inoculation of greenhouse-grown lettuce with E. coli O157:H7 or S. Typhimurium; the leaf samples were collected after 0, 24, and 48 h of treatment. Bacteria from inoculated leaves were enumerated on tryptic soy agar plates (and also on MacConkey's and XLT4 agar plates), and the recovered counts were statistically analyzed. Cut lettuce leaves showed E. coli O157:H7 reduction between 3.25 and 6.17 log CFU/leaf, whereas S. Typhimurium reductions were between 2.94 log CFU/leaf and 5.47 log CFU/leaf depending on the SE treatment durations, from initial levels of ∼7 log CFU/leaf. SE treatment of lettuce in planta, before bacterial inoculation, reduced E. coli O157:H7 and S. Typhimurium populations by 1.88 and 2.49 log CFU after 24 h and 3 h, respectively. However, SE treatment after bacterial inoculation of lettuce plants decreased E. coli O157:H7 populations by 3.04 log CFU (after 0 h) with negligible reduction of S. Typhimurium populations. Our findings demonstrate the potential of SE as a plant-based method for decontaminating E. coli O157:H7 on lettuce during pre- and postharvest stages in hurdle approaches.     

Using lytic bacteriophages to eliminate or significantly reduce contamination of food by foodborne bacterial pathogens

Bacteriophages (also called ‘phages’) are viruses that kill bacteria. They are arguably the oldest (3 billion years old, by some estimates) and most ubiquitous (total number estimated to be 10³⁰–10³²) known organisms on Earth. Phages play a key role in maintaining microbial balance in every ecosystem where bacteria exist, and they are part of the normal microflora of all fresh, unprocessed foods. Interest in various practical applications of bacteriophages has been gaining momentum recently, with perhaps the most attention focused on using them to improve food safety. That approach, called ‘phage biocontrol’, typically includes three main types of applications: (i) using phages to treat domesticated livestock in order to reduce their intestinal colonization with, and shedding of, specific bacterial pathogens; (ii) treatments for decontaminating inanimate surfaces in food‐processing facilities and other food establishments, so that foods processed on those surfaces are not cross‐contaminated with the targeted pathogens; and (iii) post‐harvest treatments involving direct applications of phages onto the harvested foods. This mini‐review primarily focuses on the last type of intervention, which has been gaining the most momentum recently. Indeed, the results of recent studies dealing with improving food safety, and several recent regulatory approvals of various commercial phage preparations developed for post‐harvest food safety applications, strongly support the idea that lytic phages may provide a safe, environmentally‐friendly, and effective approach for significantly reducing contamination of various foods with foodborne bacterial pathogens. However, some important technical and nontechnical problems may need to be addressed before phage biocontrol protocols can become an integral part of routine food safety intervention strategies implemented by food industries in the USA. © 2013 Society of Chemical Industry     

Comparative utility of hermetic and conventional grain storage bags for smallholder farmers: a meta-analysis

Postharvest management is critical to attaining household food, nutrition, and income security. Hermetic grain storage bags offer an effective pesticide-free way to protect stored grain against fungal and insect infestation. We evaluated articles indexed in the Web of Science that included experiments comparing the storage efficacy of conventional and hermetic storage bags based on grain germination rate, insect infestation, physical damage, mycotoxin contamination, and changes in weight and moisture content. Compared with grain stored in hermetic bags, grain stored in conventional bags lost 3.6-fold more seed viability, contained 42-fold more insects, had 11-fold more physical damage, and lost 23-fold more grain weight, while grain moisture levels were similar for both hermetic and conventional storage bags. Mycotoxin contamination levels were not as frequently assessed. Levels could be low in grain stored in both types of bags, or levels could be low in hermetic bags and significantly higher in conventional bags. The improved properties of grain stored in hermetic bags can increase food security and household income by providing safe storage options for maintaining seed germinability, and for consumption and/or sale when food supplies are high, or when prices are low. Hermetic bags are economically feasible for use by subsistence farmers in Sub-Saharan Africa for grain for household consumption and for carrying-over seed for planting in the next season. Additional studies are needed to verify the mycotoxin contamination results and to determine if there are differences in functional food characteristics, e.g. flavor and cooking properties, that have not been as comprehensively studied. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

楚雄州常见食用菌重金属污染及安全评价

目的调查楚雄州常见食用菌重金属含量水平,评估食用菌中重金属污染程度及健康相关风险。方法采用石墨炉原子吸收光谱法和原子荧光光谱法对汞(Hg)、镉(Cd)、铅(Pb)、砷(As)的含量进行测定。单因子污染指数法进行污染评价。结果 86份食用菌样品中重金属检出率为100.00%,重金属总体超标率为44.19%,Hg超标率高于Cd、As、Pb(P0.01);同一种重金属在不同品种以及不同地区采集的食用菌样品中含量存在显著差异。食用菌样品质量评价为三级;干食用菌和新鲜野生牛肝菌的食品安全指数(international food standard,IFS)大于1。结论食用菌中的Hg、Cd、Pb、As等4种重金属污染现状不容乐观,野生牛肝菌重金属污染程度和食品安全风险等级均较高,对人体有一定的健康危害,应高度关注并进行风险管理。     

食品污染物残留的快速检测技术应用综述及展望

近年来,食品安全问题层出不穷,食品安全问题正受到人们前所未有的关注。食品中的有害物质严重威胁人类的身体健康,对其含量进行快速准确分析具有重要意义。快速检测技术比通常的检测技术具有更快的检测速度,且装置便携、易于实现在线现场检测,在食品安全分析中发挥了重要作用;本文简单介绍了快速检测技术在食品污染物残留检测中的运用,包括检测食品中的农药残留、兽药及饲料添加剂残留、重金属残留、生物性污染物残留等,对检测方法的优点和不足做了透彻的分析,并展望其发展方向,以期为进一步开展食品安全快速分析研究提供参考。