Abstract:

Hydrogen peroxide was used to decolorize insoluble dietary fiber (IDF) from apple pomace to improve its color and quality. Response surface methodology was applied to optimize decolorization conditions. Moreover, decolorized IDF was measured for functional properties. The best decolorization results were observed when IDF was treated with 5% hydrogen peroxide at 80 ℃ and pH 12 for 180 min with a liquid-to-solid ratio of 4:1 (mL/g). After decolorization under the optimized conditions, the CIE L*, a* and b* and whiteness were 62.65, －1.47, 12.48 and 60.59, respectively, and the water-holding capacity and swelling capacity increased to 1802.96% and 13.73 mL/g, respectively.

Key words: apple pomace, insoluble dietary fiber, decolorization, water-holding capacity, swelling capacity