Abstract:

To optimize the extraction of anthocyanins from black berry slurry based on pectinase treatment, a Box-Behnken experimental design for three pectinase hydrolysis conditions (namely, pectinase loading and reaction time and temperature) was used to provide experimental data for creating a quadratic regression model reflecting the relationship between the extraction yield of anthocyanins and the hydrolysis conditions and based on this, response surface methodology was used to optimize these hydrolysis conditions. The Design Expert software was employed to inversely resolve the created quadratic regression model, the results indicated that pectinase loading of 0.21%, reaction time of 1.46 h and reaction temperature of 42.7 ℃ were found optimum and that under the optimized conditions, the predicted value of the maximum extraction yield of anthocyanins was 0.645 mg/g, in close agreement with the experimental value. Analysis of pairwise linear correlation among the content of anthocyanins and Hunter colour L*, C* and h values was carried out, and it was found that C* value could represent the content of anthocyanins to a certain extent.

Key words: blackberry, anthocyanins pigment, pectinase, response surface methodology