What happens to food when it enters the stomach?

When food enters the stomach the mixing waves generated from the stomach, churn the food with gastric juice (which is made up of the enzyme pepsin and rennin, and hydrochloric acid). Carbohydrates leave the stomach the quickest. Proteins take longer, and fats take the longest to leave the stomach. The stomach is impenetrable to most materials into the blood (except for water, alcohol, salts and drugs), until they reach the small intestine.  bobbbb