Excursus
Aging of Rice Wine and Maize Wine: Chang et al. (2002) found in their study on rice wine and maize wine that the aging effects of sonication of wine depends on the kind of wine. So was the ultrasonic aging of rice wine regarding the pH value, the alcohol content, acetaldehyde, flavor and sensory qualities significantly better than the ultrasound-assisted aging of maize wine. For both, the rice wine and the maize wine, the aging time was considerably reduced (from 1 year to 1 week or 3 day).