Proteolysis

Cut the peptide bond. Hydrolysis of the peptide bond and need water for it. Can do it:

-          Enzymatic protein hydrolysis: basis of protein digestion (peptidases or proteases like trypsin, chemotropism). The enzyme will cut the protein at a specific place. Important with respect to digestion and fermentation. Eg. soy sauce and fish sauce usually fermented, obtained from protein hydrolysis. It is more than denaturation; you disintegrate de protein to some extend. Eg. in cheese making important, camembert cheese, the interior part of cheese becomes liquid because the protein is being disintegrated after the fermentation. This is because there are microbiological enzymes present fermenting the cheese.

ü  Endogenously enzyme present: eg. Raw ham. The enzymes of the meat are slowly digesting the meat. There is no outgrowth of bacteria, it is an auto degradation.

ü  In industry food are also enzimaticaly hidrolised in reactors.

-          Chemical hydrolysis: add sodium hydroxide, not used. Hydrochloric acid hydrolysis is largely use (collagen is chemically partially hydrolyzed in production of Maggi cubes), also in production of gelatin. Proteins are chemically hydrolyzed with hydrochloric acid. This is done to enhance the flavors. Acid and alkaline also use to determine the amino acid composition of a protein. Advantage of this method is that some proteins are degraded and split off (asparage into xxx).

-          When proteins are hydrolyze we get peptides and it is important because it give flavor. But it can be further degraded and putrefaction takes action (spoilage)