Before yeast propagation, the wort should be placed in the wort sterilization tank at 100℃ for at least 30 minutes. After this process, the wort should be cooled to 14℃-16℃ for later use.
Cellars should be kept clean and well-insulated to reduce any loss of cold air. The temperature should be controlled between 5℃ and 6℃.
During the low foaming period of beer fermentation, the temperature will rise about 0.9°C to 1.0°C per day.
The standard pitching temperature for lager fermentation is 5-8°C
The final temperature of the fermentation process is typically maintained at 4 to 5 ℃ to promote yeast coagulation and sedimentation.
The secondary fermentation process usually lasts 7-10 days, after which wine temperature gradually drops to 0-1℃, marking the beginning of the storage and maturation phase.
The new secondary fermentation process has a wide initial temperature control range (3°C to 13°C), which can diacetyl content. In a subsequent phase, the beer is stored at a low temperature (between -1°C and 0°C) for a defined period (7-14 days) to achieve optimal CO2 saturation and clarify the beer.
Should temperatures exceed 20℃, the level of fermentation by-products will increase accordingly. In this case, higher pressure settings are required to suppress the production of fermentation by-products.
The standard temperature for pressure fermentation is 10-14°C, with an upper temperature limit of 14-20°C. Maintain this temperature until the dione precursors are completely reduced.
Unitank fermentation: The hot wort is transferred to a whirlpool tank to remove the hot break and hops, then cooled to the pitching temperature of 6°C-8°C via a plate heat exchanger. After the fermentation starts, the pitching temperature is maintained for 3 days, then the temperature is raised to 10°C and maintained at this level for the main fermentation. Once the diacetyl content falls below 0.1mg/L, slowly cool the system to 5℃ at a rate of 0.3℃/h and continue cooling as necessary. If the temperature remains at 5°C and for 24 hours. Following this, discharge or recover the yeast, before gradually cooling to 0°C-1°C at a 0.1°C/h rate. If the temperature does not maintain at 5°C, continue cooling to 0°C-1°C at a rate of 0.1°C/h and discharge the second yeast after 24 hours.
Unitank high-temperature fermentation: The longest fermentation period is 18 to 21 days, while the shortest is only 12 to 15 days. Once the wort has been passed through a whirlpool tank to remove hops and hot breaks, it is cooled to a temperature of 9.5°C to 10°C using a plate heat exchanger. The cold breaks are then removed using a flotation method. At the same time, sterile air is introduced into the system to ensure that the dissolved oxygen level reaches 7-8 mg/L. The wort is kept at 10 to 11℃ for 36 hours for yeast propagation, and then the temperature is raised to 12℃ for the main fermentation process. After about 2 days of fermentation, increase the tank pressure to 0.08-0.1 MPa, and the temperature is gradually raised to 16°C to continue fermentation and reduce diacetyl naturally and efficiently. Starting from days 7 to 9, the temperature can be reduced gradually over the next 4–5 days, to facilitate post-maturation and CO2 saturation. The yeast is discharged and recovered on the second day following a decline in temperature to 0°C.
