Synergism of sonication and microwave on phytochemical and physicochemical capacity of sugarcane-mint blend juice

Abstract

The sugarcane (Saccharum officinarum L.) juice, a beverage with fascinating track record of health promoting potential, loaded with phenolics, flavonoids, the bioactives, is capable of high antioxidant activities. The mint is a reliable herbal plant, with loads of phytochemicals and hundreds of food applications. However, sugarcane juice added with mint is normally consumed without any processing and preservation. Therefore, it is important to employ green processing technologies on sugarcane-mint juice blend, in order to process and preserve this nutritional juice with optimum retention of bioactives. In the current study sugarcane-mint blend juice was developed to study the synergistic effect of sonication (20 kHz, 70% amplitude, 5, 10 and 15 min) and microwave (90 °C, 400 W, 120 s) on pH, titratable acidity, total soluble solids (TSS), total phenolics (TPC), total flavonoids (TFC) and antioxidant activity of developed beverage, at 7 days interval, during 21 days of storage period. Increment in sonication time and advancement in storage days, both resulted in an increase in pH, and decrease in titratable acidity and TSS of blend juice. Sonication for 15 min along with microwave exhibited significant (p ≤ 0.05) results in terms of rise in TPC, TFC and antioxidant ability of blend juice, as compared to 10 and 5 min, sonication. Whereas, untreated juice samples exhibited significantly (p ≤ 0.05) less contents of TPC, TFC and antioxidant capacity, which were further significantly (p ≤ 0.05) decreased during 21 days of storage. Our results highlighted the significance of synergism of sonication and microwave in improvement of physicochemical and phytochemical quality of sugarcane-mint blend juice.