The wort steaming process is generally divided into two stages. First stage. The wort is filtered by the grain bed. This is called “first wort”. Second stage. Spiking – We wash out the remaining wort with hot water. This is known as second wort or spiked wort.
The following are the instructions for obtaining the first wort.
First, hot water (76-78°C) is pumped from the bottom of the fermenter and injected between the false bottom and the bottom of the fermenter. The water level is just above the false bottom to get rid of the air at the bottom.
Pump the saccharification mixture into the percolator while starting the rake at the right time to mix the mixture well.
Let the wort stand for 15-20 minutes to allow the spent grain to settle down and form a grain bed.
Then start boiling. Alternately opening and closing the valve, the wort comes out of the percolator and is pumped back into the percolator until it becomes clear. This takes 5-10 minutes of recirculation.
Then the boiling really starts – the boiling port is opened and the flow rate of wort is controlled.
After some time (halfway through the process), the grain bed begins to tighten and the wort flow rate slows down significantly. At this point, close the wort discharge valve and start the rake to loosen the grain bed.
Then restart the ratter, still pumping back the cloudy wort that flowed out at the beginning, until the wort becomes clear again. Stop raking when the top surface of the grain bed is just exposed, which means the first wort filtration is complete.