Simultaneous debittering and clarification of enzyme mediated mixed citrus juice production

Abstract

Assam lemon, Kachai lemon and Pomelo are the three different types of abundantly available lemons in North-East India. The present article emphasizes on the debittered juice production from these three citrus fruits followed by optimization studies adopting Simplex centroid mixture design (SCMD) based approach. Moreover, optimization of simultaneous debittering and clarification has been carried out by response surface methodology (RSM). A maximum debittering (51.87±1.84%) and clarification (95.69±1.15%) have been observed at 42.66°C when the bitter lemon juice was incubated for 1.73 h with 38.51 IU and 6.13 IU tannase and polygalacturonase, respectively. The quantification of released gallic acid and naringin were estimated through HPLC analysis. The obtained results exhibited that the treated juice released 0.46 mg/mL of gallic acid while naringin was reduced from 0.19 mg/ml to 0.0019 mg/ml. Biochemical analyses of the treated juice exhibited significant increase in reducing sugar, total sugar and antioxidant property (p ≤ 0.001) than that of the untreated juice while other biochemical and elemental compositions remain unaltered.

Keywords

• Mixed citrus juice
• Simplex centroid mixture design
• Simultaneous debittering and clarification
• Response surface methodology
• Enzymes