Studies on the Constituents and Processing Methods of Japanese Chestnut

Part VII. Several problems under a current processing method

Abstract

Investigations on the problems in the processing to make heavy syrupped product of Japanese chestnut were carried out.
It was proved to be effective to cut off the vertical surface part as possible as thin and the other parts as possible as uniformly in order to increase the yield of edible portion by hand-peeling of the endcarp with a knife. However, the removed thickness of the apex, the fruit stalk and the suture parts was indifferent to the yield.
The ratio of peeled portion to whole edible portion rather than to whole nut including the husk was more suitable as an indicator of peeling yield from the view point of processing. Since the difference of the yield when the surface is peeled in 1mm depth and that of the current hand peeling differed considerably from variety to variety, there is problem to be solved for the current peeling method.
The amount of gas outbreak in edible portion during warming process increased along with the raise of water temperature especially from 50° to 60°. Hence it seemed to be adequate to warm at 60-65° in order to eliminate the inner gas of the edible portion of chestnut.