Optimising clarification of carrot juice by bacterial crude pectinase

Uzuner, Sibel
Çekmecelioğlu, Deniz
This study was undertaken to search for potential use of crude bacterial pectinase enzyme produced from Bacillus subtilis grown on hazelnut shell hydrolysate in clarification of carrot juice and to optimize the enzyme load, pH and time using the Box-Behnken response surface methodology (RSM). The carrot juice was treated with the crude pectinase enzyme (5.60 U mL(-1)) at different concentrations (0.1-0.5%), pH (4-7), and time (2-6 h). The obtained enzyme was also compared with commercial fungal pectinase at identical conditions. RSM provided optimal clarification conditions of 0.5% (w/v) enzyme load, 7.0 pH, and 6 h of time estimating 100% clarity, whose experimental counterpart was 94.47 +/- 0.01%. High values of coefficient of determination (R-2 = 0.9631), predicted R-2 (0.8989) and insignificant lack-of-fit (0.12) also showed that the model was successful in predicting % clarity for various combinations. This study also indicated that crude bacterial pectinase providing about 95% clarity is superior to commercial fungal pectinase, which gave 78% clarity under tested conditions, in terms of clarification ability for carrot juice.


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Citation Formats
S. Uzuner and D. Çekmecelioğlu, “Optimising clarification of carrot juice by bacterial crude pectinase,” INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY, pp. 2707–2712, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46526.