Fermentation process operating procedures

Process flow chart

The fermentation process operating procedures

1. Fermentation tank cleaning 

(1) When the beer is finished in the fermentation tank, open the pressure relief valve of the cleaning pipeline to release the pressure to 0 MPa; start to connect the CIP cleaning pipeline and the recovery pipeline, and open the sampling valve.

(2) Check whether the concentration of lye and disinfectant in each washing tank meets the process requirements; check whether the valve is tight.

(3) Open the outlet valve and washing pump of the clean water tank, and rinse the fermentation tank with water until there is no foam or obvious material in the water. After washing, close the washing pump and the outlet valve of the clean water tank, and wait for the residual water in the fermentation tank to be drained.

(4) Open the outlet valve of the lye tank and the washing pump, adjust the return valve appropriately, and wash with warm lye for 30 minutes; after washing with alkali, close the washing pump and the outlet valve of the lye tank, and wait for the residual alkali in the fermentation tank Reflow is clean.

(5) Open the outlet valve of the hot water tank and the washing pump, rinse the residual alkali in the fermentation tank with warm water until the water liquid flowing out of the fermentation tank is neutral. Drain the residual water in the tank.

(6) Open the outlet valve of the disinfectant tank and the washing pump, adjust the return valve appropriately, and circulate the disinfectant for 30 minutes; after the sterilization is completed, close the washing pump and the outlet valve of the disinfectant tank, and wait for the disinfectant in the fermentation tank to return cleanly.

(7) Note: If the fermentation tank has not been used for more than 24 hours after sterilization, the fermentation tank must be re-sterilized before use.

(8) During the cleaning process, it is necessary to check whether the washer or the washing ball is unblocked. If there is any abnormality, the tank must be opened for maintenance immediately, and re-washed and sterilized according to the cleaning procedure.

(9) Note: During the cleaning process, it is necessary to check the cleaning residues in the cleaned fermentation tank and related pipes to avoid food safety accidents.

2. Yeast adder for sterilization 

(1) The yeast adder must be rinsed with clean water after each use.

(2) Before sterilization, check whether the inside of the yeast adder is clean, check whether there is yeast mud or impurities left in the pipeline, and rinse it again, then connect the pipeline to prepare for sterilization.

(3) Use hot water higher than 90℃ for 20 minutes to sterilize before passing the material;

(4) Note: Just after the prohibition of sterilization, add yeast before the temperature drops.

3. Fermentation operation 

(1) Before the wort enters the fermentation tank, sterilize the wort pipeline with hot water higher than 90℃ for 20 minutes (open the sampling valve on the pipeline during sterilization).

(2) Check whether the pipeline connection is correct, close the sampling valve of the fermentation tank, and open the exhaust valve and the bottom valve of the tank.

(3) After high temperature sterilization and inspection, start to inject wort into the fermenter. When the wort flows out from the head pipeline, the operator immediately switches the valve to the state of entering the fermenter, and pays attention to checking;

(4) 5~15 minutes after the wort is put into the tank (reasonable design time according to the volume of the tank), start adding yeast. In addition, the wort enters the tank and begins to add oxygen, and the oxygenation amount reaches 8ppm. It is evenly mixed with the wort to form fine air bubbles until the wort enters the tank.

(5) After the wort is put into the tank, the operator pushes the accumulated wort in the pipeline into the fermentation tank with hot water, and then closes the bottom valve of the tank.

(6) After the wort in the fermentation yeast is full, record the temperature when the tank is full, measure the sugar content of the full tank, and measure the number of yeast in the full tank after 4 hours. If the number of yeast in the full tank is less than 12 million/ml, an appropriate amount of yeast should be added immediately.

(7) Note: Observe and control the fermentation state and the temperature and pressure in the tank at any time, and seek truth from facts and make records in a timely manner.

Sugar measurement requirements, from the time the tank is full, the sugar is measured once on each shift and after get off work. When the temperature rises and pressure is approached, the sugar measurement frequency should be appropriately increased until the tank is sealed and the pressure is increased; the temperature, pressure and corresponding time must be on and off each shift. each record once;

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4. Fermentation temperature control and cooling operation 

(1) During the main fermentation period or the (heating) treatment of diacetyl after the wort is full, the temperature must be timely (or automatically controlled) to maintain the temperature required by the process.

(2) During the boosting period, timely (or automatically control) the temperature to maintain the temperature required by the normal process;

(3) When cooling starts, the temperature is lowered to 5°C at a rate of 0.3~0.5°C/hr;

(4) From 5°C, cool down at 0.1°C/hr until -1°C~0.5°C and then store;

(5) During the beer-making process, always control the temperature of the beer liquid at -1°C~0.5°C. When the beer is finished, immediately close all refrigerant valves.

5. Yeast recovery, discharge and addition 

(1) When the fermentation broth is cooled to below 5°C, the yeast can be discharged;

(2) During the post-storage (-1°C~0.5°C) period, discharge the residual yeast once a day (or before filling the beer) until the beer is finished; if the post-storage (-1°C~0.5°C) time is longer than two weeks, every Discharge yeast once every three days until the liquor is finished;

(3) If the yeast is recycled, the yeast adder needs to be sterilized before use;

(4) When the yeast is recovered for use, the yeast head part (dead yeast) needs to be drained into the ditch, and then connected with a sterilized hose to take the yeast seed mud into a sterile container, add it to the yeast adder, and open the cold wort valve together with the cold wort. into the fermenter.

Beer fermenters