Effects of ohmic and conventional heating on anthocyanin degradation during the processing of blueberry pulp

AbstractThe present work evaluates the anthocyanin degradation in blueberry pulp after thermal treatment using ohmic and conventional heating. The ohmic heating technology was studied using a rotatable central composite design, and the variables studied were voltage and solids content. The anthocyanin content of the samples was determined using HPLC. The results show that degradation increased with both increasing voltage and increasing solids content. The comparison between ohmic and conventional heating showed that when lower voltage levels were used, the percentage of degradation was lower or similar to those obtained during conventional heating. However, for high electric fields, the pulp processed using ohmic heating exhibited higher anthocyanin degradation