Characterization of lemon peel powder and its application as a source of pectin degrading enzyme in clarification of cloudy apple juice

The presence of pectin in the apple peel creates undesirable turbidity and sediment in the final juice and hence clarification is a necessary step for producing consumer-friendly apple juice. This study aimed at evaluating the potential of lemon peel powder as a source of reusable pectinase enzyme in the clarification of apple juice. In this study, optimization of the amount of lemon peel powder addition and incubation time was carried out to produce an apple juice of acceptable clarity. Lemon peel powder as an enzyme source having an activity of 2804.4 U/g could be successfully used up to 5 cycles of pectin hydrolysis. Pectinase enzyme in the lemon peel powder had greater stability at 4 °C with an 11.11% decrease in enzyme activity on 60th day of storage. Treatment with 0.5% w/v lemon peel powder at an incubation time of 90 min was found to be optimum as it produced a clarified apple juice with good sensory acceptability. Lemon peel powder as a naturally immobilized pectinase source was found to be effective in producing clear apple juice. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05270-7.