Unraveling the efficacy of different treatments towards suppressing limonin and naringin content of Kinnow juice: An innovative report

Abstract

Bitterness in juice significantly affects consumer acceptability as well as its shelf life. Juice extracted from Kinnow fruit becomes bitter due to the presence of limonin and naringin. Therefore to remove bitterness from Kinnow juice, different debittering methods have been studied. These methods include hot water treatment, lye treatment (1–2%), Florisil®, ß-cyclodextrin (0.5–2.5%) and their optimized treatment (NaOH 1.5% + Florisil® 3% + ß-cyclodextrin 2%). Significant effect of treatments on pH, acidity, and TSS (Total soluble solids) was observed. Control (P1) and treated juice samples [lye treated juice (1.5%) (P2); lye treated juice (1.5%) + Florisil® (3%) (P3), and juice from optimized treatment (P4)] were studied for the presence of bioactive compounds and antioxidant properties. The antioxidant profiles of control and treated juice samples were compared using different antioxidant assays. Phenolic compounds in debittered juice (P4) were significantly higher (94.5 mg GAE/100 mL) as compared to control (P1) (90.1 mg GAE/100 mL). HPLC was performed to check the presence of bitter compounds (limonin and naringin) in control and treated juice. A significant decrease in the concentration of limonin (124.45–57.89 µg/mL) and naringin (2.38–1.26 µg/mL) was observed in the selected combined treatment.