Liu Xiumei: How to rationally view the excessive indicator bacteria?

Wu Qingping, Academician of the Chinese Academy of Engineering, Vice President of the Chinese Society of Food Science and Technology, Honorary Director of the Institute of Microbiology, Guangdong Academy of Sciences

Liu Xiumei, Honorary Vice President of the Chinese Society of Food Science and Technology, former Chief Food Safety Expert of the Institute of Nutrition and Health, Chinese Center for Disease Control and Prevention

The total colony count has received a lot of attention in recent years' random inspections, and the popularity is stronger than that of some pathogenic bacteria. In the national food safety standards, the current microbial index limits include pathogenic microbial indexes and indicative microbial indexes. The former is mainly the limit of pathogenic bacteria, and the latter includes the total colony count, coliform group, mold, and yeast.

Expert opinion 1: Total colony count and coliform group are commonly used indicative microbial indicators at home and abroad. They are not directly used to evaluate food safety. They are mainly used to evaluate the hygiene and quality of food and its production environment.

The total number of colonies is an indicative microbial indicator, not a pathogenic bacteria indicator. It is mainly used to evaluate the cleanliness of food and the production and processing environment, and can be used to determine the degree of bacterial contamination and sanitary quality of food. Coliform bacteria mainly come from the intestines of humans and warm-blooded animals. The coliform bacteria index in food mainly reflects the possibility of food being directly or indirectly contaminated by feces. There may be intestinal pathogens in feces, so the coliform bacteria index indirectly indicates the possibility of food being contaminated by intestinal pathogens.

Expert opinion 2: Foods with excessive total bacterial counts and coliform bacteria indicate that their hygiene conditions do not meet basic hygiene requirements and may affect food quality

Foods with excessive total bacterial counts and coliform bacteria indicate that their sanitary conditions do not meet basic sanitary requirements. Bacterial growth accelerates food spoilage and utilizes the corresponding nutrients in food, causing the food to lose its edible value. There is also an important standard in my country's food safety standards, "National Food Safety Standard General Hygiene Specifications for Food Production" (GB 14881). Its appendix clearly stipulates that food production companies should monitor your production environment and national products, mainly monitoring total bacterial counts and coliform bacteria. Because they are indicative, they will react to these indicators before pathogens are discovered. This indicator is still very important in food production quality control.

Expert opinion 3: The colonies observed in the total colony count test are basically non-pathogenic bacteria and do not pose a direct risk to human health or disease.

Under the conditions of total colony count determination, the bacteria detected in meat, milk, aquatic products and other foods are mainly spoilage bacteria, such as Bacillus, Enterobacter, Enterococcus, etc.; anaerobic, mesophilic and bacteria suitable for growth in extreme environments are not easy to reproduce and difficult to detect. Whether the colonies detected in food have a pathogenic risk requires further judgment using reasonable inspection and testing technology. From the sampling information officially released by the State Administration for Market Regulation in 2021, it was found that the foods with unqualified total colony counts were mainly cooked meat products and pastries, suggesting that the supervision and management of ready-to-eat foods should be strengthened.

Expert opinion 4: Non-standard operation of food production raw materials, processing environment or processing links is the main reason for the excessive total bacterial count and coliform group

If the total bacterial count and coliform group of a food are found to exceed the limit of national food safety standards, it may be because the raw materials, auxiliary materials, packaging materials, etc. of the food are contaminated by bacteria; the sanitation of the food production and processing environment is too poor, and the equipment and tools are not disinfected properly; the practitioners do not pay attention to personal hygiene such as washing hands and changing clothes, and the operation is not standardized, etc. If the food is in a state of microbial contamination and scientific control measures are not taken in time, it will face the risk of contamination by pathogenic microorganisms, leading to food safety problems.

Source: Tuchong Creative

Expert suggestion 1: Food producers and operators should enhance their awareness of food safety risk management and attach importance to microbial risk monitoring and risk control in the production and operation process

Food producers and operators should strengthen their awareness of food safety risk management and take targeted measures based on the links we have discovered above:

1. Strengthen food safety knowledge training for employees, cultivate good hygiene habits, and strictly implement hand washing and disinfection system;

2. Carry out microbial monitoring in food production and processing environments and do a good job of disinfection and sterilization;

3. Strengthen the microbial quality control of food raw materials and production water, and strictly control the safety of production sources;

4. Carry out regular cleaning and disinfection of food production equipment, facilities, and tools to avoid secondary contamination of food. The ultimate goal is to effectively control contamination by pathogenic microorganisms.

Expert suggestion 2: Consumers should be rational about the total colony count and coliform group indicators

Consumers see some unqualified items in the random inspection, do not understand basic scientific knowledge, and are very scared when they see a lot of bacterial contamination. They even had a panic mentality in the past few years. Through today's interpretation and future training, first, we hope that consumers will understand the substantive significance of this indicator and will not cause direct harm to health. First of all, you need to understand it. Second, you need to know what to do at the last checkpoint of food intake. Some of them need to be properly heated or reprocessed. If they are done well, even if the total number of bacterial counts exceeds the standard, it will not bring any risks.

The "Scientific Interpretation of Food Safety and Health Hot Topics Media Communication Conference" has been held for 10 consecutive years since 2012. Every year, authoritative experts are invited to provide scientific interpretations of the annual food safety and health hot topics. In the form of "consensus in the scientific and technological community", it is widely disseminated through mainstream media and new media, such as television, newspapers, the Internet, Weibo, WeChat, etc. With scientific truth and fair suggestions, we will guide the public opinion on food safety in my country to gradually change in a scientific, objective and rigorous direction, and convey the positive energy of China's food safety.