How to judge the cause of contamination is fermenter contamination?
The first thing to be clear is: when making judgments, you must not subjectively rule out the contamination of the fermenter, and you must not think that the fermenter has undergone strict testing, otherwise the real cause of contamination will not be found.
First of all, let's understand the time and situation of the pollution. The fermenter/bioreactoris infected with bacteria, and the performance time after inserting the bacteria bag can be divided into three situations:
1. Severe cases usually manifest within 24-48 hours.
If it is a bacterial infection, the liquid bacteria will not germinate, and it will smell sour and odorous. Microscopic examination can see a large number of live bacteria. If it is a mold infection, white hyphae will germinate around 24 hours. Microscopic examination can determine whether it is mold. After 48 hours, the spores will turn green or other colors.
2. Mild infections may manifest in 5-7 days
This is usually a bacterial or yeast infection. Usually, gray hyphae appear in the middle of the fungus bag (bacteria bottle), and the performance of the same batch of fungus bags (bacteria flasks) may vary.
3. Lesser bacterial infections did not manifest during the entire culture period
It didn't show any signs until the bacteria were scratched, even during the fruiting period. The surface of the material may also be normal when scratching the bacteria, but there will be dark irregular patches on the surface after scratching the bacteria, especially after rinsing. In the later stage, there will be fewer buds, spit yellow water, and rotten mushrooms.
Through the time of pollution performance, let's take a look at the quantity and regularity of pollution, and the bacterial bag (bacteria bottle) pollution caused by fermenter pollution. There are three important judgments:
1. Large quantity
Nowadays, fermenters are relatively large, and the number of inoculations in a fermenter can range from a few thousand to as many as tens of thousands. If the contamination of the fermenter is not detected, the contamination of the bacterial bag (bacteria bottle) must not be sporadic pollution, so that the contamination caused by the inoculation, cooling, cultivation and other links can be excluded.
2. Appears in units of the number of bacterial bags (bacteria bottles) inoculated in a fermenter
The regularity is obvious, which is the key point, that is, to keep production records, and when
there is pollution, it can be determined whether it is the bacterial bag (bacteria bottle) connected to the same fermentation tank.
3. Intermittent appearance
In a slightly more formal edible fungus factory, the contamination of the fermenter will cause the contamination of the whole batch of fungus packs (bacteria bottles) to not appear continuously.