tryptone Carrine Blank From: Wikipedia:Tryptone Tryptone is the assortment of peptides formed by the digestion of casein by the protease trypsin. Proteose Tryptone An enzymatic hydrolysate of casein (a milk protein from cow's milk, Bos taurus) made using the hydrolytic enzyme trypsin, used for the culturing of microorganisms. Bacto Tryptone Bacto-Tryptone From BD Bionutrients(TM) Techical Manual (3rd edition, revised): Bacto™ Tryptone is a pancreatic digest of casein. It was developed by Difco Laboratories while investigating a peptone particularly suitable for the elaboration of indole by bacteria. It is also notable for the absence of detectable levels of carbohydrates. Ash content is 6.6% NaCl content is 0.0% bacto-tryptone casein hydrolysate