The Effect Of Ultrasonic Treatment On The Physical And Chemical Properties Of Black Rice Wine

As a new rise of yellow rice wine, black rice wine's consumption is increasing along with the people'gradual understanding on the nutritional value of black rice wine. The traditional aging methods had so many shortcomings, such as long aging period, demand for a lot of equipment, uncontrollable factors in the aging process. Therefore, it is very meaningful for the black rice wine enterprises to develop a new technology to accelerate aging process.In this article, the influence of ultrasonic treatment on black rice wine was determined which included the phenolic substance content, color, free radical scavenging activities and organic acid content. Besides, the effect of ultrasonic treatment on the epicatechin in model wine had also been-studied.The results obtained are listed as follows:1. The total phenolic content in wine sample ? (stored in stainless steel tank for 1 years) and ? (stored in ceramic altar for 3 years) had increased significantly by ultrasonic treatment, while sample ? (added black rice pericarp pigment and stored in stainless steel tank for 2 years) had a significant decreased of the total phenolic content. Three black rice wine samples of L increased significantly, and the color change could be distinguished by eyes. The correlation analysis showed that, total anthocyanin content and L*, a*, b* of sample ? had a great correlation treated by different ultrasonic power, frequency, and time (R2?0.8828). There was a certain correlation between the total flavonoids and L* of sample ?, while the total phenolics and L* in sample ? had a certain correlation. The free radical scavenging-activity of sample ? and ? after ultrasonic treatment increased, while sample ? weakened.2. The results of phenols determination in black rice wine showed that the epicatechin content changed significantly of the three kinds of wine samples treated by ultrasonic. There were little change of the other four phenols (gallic acid, protocatechuic acid, catechin, rutin) in sample ? treated by different ultrasonic power, frequency and time, while sample ? had significant change. Sample ? treated by 80 kHz ultrasonic frequency showed specific values.3. The content of epicatechin in the model wine was reduced treated by different ultrasonic power, frequency and time, which is consistent with the change in natural aging. And changes of epicatechin in model wine had the same trend with sample I when both of them were treated by the same ultrasonic condition, which means that ultrasonic treatment do a visible favor of wine sample I's aging.4. Ultrasonic treatment led to the content of oxalic acid and lactic acid in wine sample II and oxalic acid, lactic acid, acetic acid content in wine sample III increased, while the content of tartaric acid, acetic acid, citric acid in sample II and the content of tartaric acid and citric acid decreased. The effects of different ultrasonic treatment conditions (power, frequency and time) on samples I's five organic acids were not the same, and 5 kinds of organic acid content in samples I increased treated by different ultrasonic time.