The sample retention time in the canteen is 48 hours, and the sample retention amount of each dish is not less than100g, so that the samples are separated without confusion; After 48 hours, pour the remaining vegetable samples into the trash can, and thoroughly clean and disinfect the sample box to avoid cross-contamination.

It should also be noted that the dishes in the sample box must be cooled before they can be covered and put into the refrigerator. Hot dishes can't be put in the refrigerator. On the one hand, it will increase the temperature in the refrigerator, on the other hand, it will accelerate the deterioration of the sample dishes and fail to achieve the expected results.