Sonication Effect on Bioactive Compounds of Cashew Apple Bagasse

This study describes some effects of high-power ultrasound on cashew apple bagasse. The main objective was to develop an optimized process for sonication of cashew apple bagasse, evaluating the effect of ultrasound on antioxidant compounds. To define the best conditions for sonication, a 2(3) factorial central composite design was used changing the independent variables: bagasse/water ratio, ultrasonic power intensity (W/cm(2)), and processing time (min). Antioxidant compounds such as vitamin C, beta-carotene, and total phenolic compounds were determined. The total antioxidant capacity (ABTS(2,2 AZINO BIS (3-ethylbenzo thiazoline 6 sulfonic acid) diammoninum salt and DPPH (2,2-Diphenyl-1-picryl-hidrazil)) was also evaluated. A thermal treatment was carried at the highest temperature reached after sonication (51 A degrees C) to evaluate the heat effect due to a temperature increase during processing. Sonication changed the bagasse aspect from a fibrous residue to a pleasant yellow puree. The maximal concentration of vitamin C, phenolics, and beta-carotene was obtained when the processing conditions were as follows: bagasse/water ratio of 1:4 (w/w), ultrasound power intensity of 226 W/cm(2), and 6 min of processing. The high total phenolic content (2186 mg of gallic acid/100 g DW), vitamin C (148 mg/100 g DW), and beta-carotene (12 mg/100 g) obtained proved the sonication efficiency. The antioxidant activity determined by the DPPH and ABTS assays confirmed the suitability of ultrasound for the preparation of antioxidant-rich cashew apple bagasse puree.