The dirt on the walls of the fermenter is a mixture of inorganic and organic matter, which is difficult to clean with a single cleaning agent. If only caustic soda is used for fermenter cleaning, it only serves to remove organics. Only when the cleaning temperature reaches above 80 ℃, can a better cleaning effect be obtained; when cleaning, single nitric acid is used for cleaning, which only has a certain effect on inorganic substances and is almost ineffective for organic substances. Therefore, fermenter cleaning requires an alkaline cleaning solution and an acidic cleaning solution.
Fermentation tanks are cleaned first and then sterilized. The prerequisite for effective sterilization is that the dirt is thoroughly cleaned. In actual production operations, it is always cleaned first and then sterilized.
Cleaning step of the fermentation tank: discharge the residual carbon dioxide gas in the tank. Compressed air displaces carbon dioxide for 10-15 minutes. (depending on the compressed air flow). The yeast remaining in the fermenter was rinsed with clean water, and the fermenter was rinsed intermittently with hot water at 90°C to warm it up. Disassemble the discharge combination valve and aseptic sampling valve, use a special brush dipped in lye to clean it, and reinstall it. The fermenter is cleaned by circulating hot alkaline water over 1.5-2% at 80°C for 30 to 60 minutes. Rinse the fermentation tank intermittently with hot or warm water to make the discharge liquid neutral, and intermittently rinse the fermentation tank with cold water to room temperature. Wash with nitric acid solution with a concentration of 1% to 2% for 15 minutes. The fermenter was rinsed with water to neutralize the drain.
It is believed that through strict cleaning and disinfection, the stability of the brewed beer will be further improved.
Post time: Mar-15-2022