It is recommended to choose pure natural enzymes without additives. Now many enzyme manufacturers are adding some chemicals to reduce the cost of enzymes and improve the effect. Enzyme is not a medicine, and it can't have obvious effect like taking medicine. Personal advice, do it yourself, and then test it after it is done, so it is safe to drink. I cook, too. The barrel used is made of round origin and 304 stainless steel, which has better sealing and light avoidance. Ordinary barrels are very troublesome to exhaust and stir. If there is any problem that has not been solved, please trust me privately. I hope it can be adopted. Thank you.