Effects of Ultrasonic Treatment on Biologically Active Ingredients of Perilla Drink

Ultrasound can be applied as an efficient and green technology for various food processes. This study focused on evaluating the influence of ultrasonication and thermal treatments on the stability of antioxidant components in perilla drinks. Specifically, it compared the impact of ultrasonic treatments lasting 5, 10, and 15 minutes at frequencies of 58 kHz, 132 kHz, and 192 kHz with thermal treatment ranging from 70°C to 90°C, aiming to explore the effects of ultrasonic treatment on biologically active compounds in perilla drink, including polyphenols, flavonoids, anthocyanins, reducing sugars, DPPH, total soluble solids (TSS), and pH. Findings revealed no significant differences in TSS and pH among the sonicated, heat-treated, and untreated samples. However, the increase in flavonoid content under ultrasound and heat treatment for 10 minutes was statistically significant compared to the control sample (p < 0.05). In addition, the experimental results indicate that as ultrasonic treatment time and temperature increased, the reduced sugar and polyphenol content also increased. However, the ability to capture DPPH free radicals decreased with increasing ultrasonic treatment time and temperature (p < 0.05). Perilla drink pasteurized using ultrasonic treatment at 132 kHz for 10 minutes maintains anthocyanin, flavonoid, polyphenol, and reducing sugar content, as well as free radical scavenging ability (DPPH), at levels equivalent to the control (no treatment) and remains the most stable among all treatments. These insights are valuable for beverage producers aiming to preserve product quality during processing and storage.