- Question: The sterilization conditions of different media are inconsistent. Can it be combined into one sterilization condition?
Answer: According to the 2015 edition of the Safety Technical Specifications for Cosmetics, the culture conditions for culturing microorganisms are as follows in Table 1. If the following sterilization conditions are not followed, the final culture results may deviate.
- Question: In practical, the microbial culture time is inconsistent with the standard culture time for some reasons. And is the culture result acceptable?
Answer: Also according to Table 1, if the culture time is inconsistent with the standard specified culture time, no matter more or less than the time range specified by the standard will affect the test results. Because the growth curve of a typical microorganism in a relatively stable environment is “S” shaped. More or less training time may have a significant impact on the test results, and others may not repeat the test results.
- Question: Can the microbial incubator be placed in the inoculation room?
Answer: No. There is a risk of cross-contamination, and if the inoculation chamber is disinfected with ozone, the ozone will affect the microorganisms those being cultured in the incubator.
- Question: Can the mold incubator and the bacteria incubator be placed in the same room for cultivation?
Answer: Yes. If you have the conditions, you can divide them into different rooms.
- Question: Can mold and bacteria be cultured in the same incubator? ( Cultured separately at different times)
Answer: No. As can be seen from Table 2, although the mold incubator and the biochemical incubator have the ability to culture bacteria, mold, and yeast, the general microbial detection is carried out simultaneously with bacteria, mold, and yeast. It is difficult to prove the validity of the test results if the culture is carried out separately in the same incubator. At the same time, the production of the company is generally continuous, resulting in continuous microbiological tests. An incubator can’t meet the requirements of actual quality control.
- Question: How to disinfect the incubator?
Answer: The incubator needs to be disinfected regularly. The general disinfectant is 75% alcohol. Since the tank material is generally stainless steel, it is not suitable to use sodium hypochlorite or benzalkonium bromide because these disinfectants are corrosive to stainless steel.
- Question: How long can it be kept after opening the bottle for the purchased medium?
Answer: The expiration date needs to be verified before it determined. Generally, it can be used within one year after opening the bottle.