Method for effectively killing sub-lethal damage bacteria generated in thermal sterilization process

Abstract

The invention discloses a method for effectively killing sub-lethal damage bacteria generated in a thermal sterilization process. The method comprises the following steps: enabling staphylococcus aureus washed with sterilized saline water to be suspended in the sterilized saline water to obtain bacterial suspension; then treating the bacterial suspension by using a thermal-ultrasonic combination sterilization method at the ultrasonic treatment frequency of 10 to 30 kHz, the treatment power of 500 to 700 w, the treatment duration of 5 to 7 min and the treatment temperature of 50 to 60 DEG C. According to the method, the possibility of restoration of the sub-lethal damage bacteria generated by thermal treatment under a proper condition is reduced, and the sterilization process is further optimized; the industrial application of the ultrasonic-thermal combination sterilization technology can be popularized favorably.

Description

technical field [0001] The invention relates to the technical field of microorganisms, in particular to a method for effectively killing sublethal damaged bacteria produced in a thermal sterilization process. Background technique [0002] Traditional thermal sterilization technology has been widely used in the food industry. It can kill various microorganisms, and the degree of sterilization can be accurately controlled. It is an effective sterilization method. However, studies have shown that heat treatment can induce bacteria to form a sublethal injury state. Sublethal lesion bacteria cannot grow and multiply normally on commonly used media, so they can evade routine detection and cause false negative results. In the process of product storage and transportation, once the pathogenic bacteria in the sub-lethal state are under suitable environmental conditions, the sub-lethal bacteria can repair themselves and return to the normal state, so the bacteria in the sub-lethal da...

AI Technical Summary

Problems solved by technology

However, studies have shown that heat treatment can induce a sublethal injury state in bacteria

Sublethal lesion bacteria cannot grow normally on commonly used media, so they can escape routine detection and cause false negative results

In the process of product storage and transportation, once the pathogenic bacteria in the sub-lethal state are under suitable environmental conditions, the sub-lethal bacteria can repair themselves and return to the normal state, so the bacteria in the sub-lethal damage state may cause food secondary damage. Secondary pollution, once it enters the human body, there will be potential hazards, which will bring serious hidden dangers to food safety and make the safety of thermal sterilization technology a challenge

[0003] Effectively killing the sublethal damage bacteria produced in the process of heat treatment is an important means to improve the effect of heat sterilization and enhance the safety of heat-processed food. However, the current effect of heat sterilization in food is only limited to the evaluation of bacteria that are completely killed by heat treatment. Sublethal damage bacteria produced during heat treatment are not involved