Lactic acid can maintain the humidity of tobacco, remove impurities in tobacco, change taste, neutralize nicotine nicotine, reduce harmful components and improve tobacco quality. Lactic acid can be used to synthesize L-lactate lactate, used as a flavoring agent for tobacco flavor. It has the function of shielding bitter and astringent taste, leaving a fresh sense of smoking in the mouth; potassium lactate is a commonly used coke-burning improver; magnesium lactate and calcium lactate can also be used as tobacco additives to improve gray gray matter.