Important safety warning! Soya beans create foam when cooking which can cause the loose hulls to move around your pressure cooker and potentially block the valve. For your safety, monitor the pot throughout cooking. If you see signs that the valve might be blocked (i.e. excess water escaping, or no steam coming out at all), remove the pot from the heat immediately. Cool the pot under the cold water tap to quickly depressurise. Declog, remove any loose hulls or excess foam, then bring back up to pressure again to continue cooking.