Effect of processing on amylase and protease inhibitor activity in tropical tubers

The effect of various processing methods on amylase, trypsin and chymo-tryp sin inhibitory activities in tubers of Colocasia esculenta (taro), Xanthoso ma sagittifolium (tannia), Solenostemon rotundifolius (Coleus, Chinese pota to), Dioscorea esculenta (lesser yam) and Amorphophallus paeoniifolius (ele phant foot yam) was studied. Among the different methods, frying was the mo st effective method of eliminating enzyme inhibitors from tubers. When cook ed by boiling, partial retention (30 to 60 %) of enzyme inhibitory activity was observed in certain tubers. Further reduction in inhibitory activity w as observed in baked/pressure cooked tubers. The study indicated that proce ssing decreased the inhibitor content significantly and the reduction of in hibitory activity was brought about by heat inactivation.