The effects of microwave and oven drying on bioactive compounds individual phenolic constituents and the fatty acids profiles of bitter orange, mandarin and grapefruit peel and oils

Abstract

Abstract Total phenol amounts of bitter orange, mandarin and grape fruit peels dried were measured between 627.21 (70oC) and 1280.03 mg GAE/100g (control), 485.50 (900 W) and 991.39 mg GAE/100g (control) and 393.03 (100oC) and 847.04 mg GAE/100g (control),respectively. The cathechin contents of bitter orange and mandarin peels dried were identified between 174.29 (100oC) and 527.54 mg /100g (control) to 160.02 (control) and 255.46 mg /100g (70oC), respectively. Also, the catechin amounts of grapefruit peels varied between 177.72 (70oC) and 446.75 mg/100g (control). Rutin contents of bitter orange peel change between 48.84 (540 W) and 380.20 mg/100g (control). Oleic acid results of bitter orange, mandarin and grapefruit peel oils were identified between 20.26 (control) and 49.82% (70oC), 7.64 (control) and 53.46% (70oC) and 40.25% (control)and 50.30% (70oC), respectively. While linoleic acid results of bitter orange peel oils are recorded between 17.08 (70oC) and 30.46% (control), the linoleic acid results of mandarin and grape fruit peel oils were identified between 18.23 (70oC) and 35.55% (control) to18.05 (70oC) and 29.28% (control), respectively.