Abstract
Cooling conditions affecting sweetness of sweet potatoes were examined and the following results were obtained.
1) Saccharification of sweet potatoes during the heating was inhibited by the addition of 1% NaCl,4% soy souce or 0.4% alum, but not by that of 3% saccharose or 2% chemical seasoning to homogenate of sweet potatoes.
2) The inhibitory action of NaCl or soy souce on sacchariflcation was changed as the function of cooking temperature; the inhibition disappeared when these were added more than 80°C. Thereforefore, in order to increase a sweetness of sweet potatoes, NaCl or soy souce should be added after sweet potatoes were softened by heating.
3) Inhibitiry activity of alum was not influenced by cooking temperature.
4) The reason why the inhibitory effecet of these additives were changed was assumed as follows: while soy souce and alum inhibited only β-amylase activity, NaCl inhibited both β-amylase and -amylase and gelatinization of starch.
