Antitryptic Activity in Stored Potatoes

Potatoes are among the several major tuber and bulb crops which contain high concentrations of proteinase inhibitors. These are the proteins which inhibit the activities of animal pancreatic digestive proteinases including trypsin, chymotrypsin and carboxypeptidases A and B and their presence in raw potatoes is potentially toxic. Potato soluble protein can comprise more than 15 per cent proteinase inhibitors and at least 13 protease inhibitors mainly trypsin inhibitors have been identified by gel electrophoresis from several exotic potato cultures. Attempts have been made to improve the nutritional value of potatoes by using different heat treatments. In pulses, it is reported that the germinated seeds contained low levels of trypsin inhibitors. However, the information on the antitryptic activity in the tubers of Indian potato varieties and the influence of sprouting and different storage temperatures on this inhibitory activity is lacking.