Trypsin Inhibitor

Proteins found in some raw plant foods (e.g. soybeans) that can inhibit digestion 

When raw, certain plant foods contain substances that can irritate the human digestive system. 

Trypsin inhibitors are present in soy protein. They block the enzyme trypsin, which is secreted by the pancreas and breaks down protein in the small intestine. Soy products are heated to high temperatures during processing to deactivate the toxin. This is why soybeans should be cooked before eating and why soybean oil must be refined.