Abstract
The extent of oxidation of vitamin C and its yield in various vegetable juices were compared for the preparations by a mixer and a juicer. Remarkable differences between them were observed in vitamin C content of several kinds of juices. Although the oxidation of vitamin C, especially in vegetables possessing higher ascorbinase-activity, was lower in the treatment with a juicer than in that with a mixer, the yield of vitamin C in juice was less in the former than in the latter because considerable amounts of vitamin C remained in residues discarded by the treatment with a juicer. Several pretreatments to prevent the oxidation of vitamin C were tested through crushing by a juicer. From the standpoint of nutritive value of juices prepared, it is presumed that leafy vegetables are preferable to be crushed by a mixer while fruits or root vegetables should be crushed by a juicer.
