We must cook the cereal to soften the starch and make it soluble in water because the enzymes in the green malt can only work on dissolved materials.The cereal is cooked under pressure to shorten the cooking time, just like a domestic pressure cooker.
The stages in cooking are:
The cooker is filled with water and milled cereal. Steam is injected directly into the mixture, and the pressure and temperature are allowed to rise, until they reach 4.3 bar and about 150°C respectively. The mixture is held under these conditions for about 30 minutes. Finally, the cooked cereal (which is like a thick porridge) is discharged under its own pressure to a holding vessel.
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