The salivary glands, stomach, pancreas, and small intestine all produce digestive enzymes. These enzymes break down proteins, carbohydrates, and fats into the units they are made up of—amino acids, sugars, and fatty acids.These tiny units are so small they can pass into the villi lining the intestine.ood is squirted from the stomach into the small intestine. Here it mixes with digestive juices from the liver and pancreas. Bile from the liver breaks up fat. Pancreatic juice neutralizes stomach acid and contains enzymes that digest carbohydrates, proteins, and fats.