화학공학소재연구정보센터
Journal of Food Engineering, Vol.123, 1-7, 2014
Ascorbic acid degradation and color changes in acerola pulp during ohmic heating: Effect of electric field frequency
The effect of the electric field frequency on ascorbic acid degradation and color changes in acerola pulp during ohmic heating was evaluated and this technology was compared with the conventional heating process. The electric field frequency was evaluated in the range between 10 and 10(5) Hz. The use of low electric field frequency (10 Hz) led to greater ascorbic acid degradation and higher color changes probably due to the occurrence of electrochemical reactions. Above 100 Hz these reactions were minimized and, as a result, ohmic and conventional heating processes showed similar degradation rates of ascorbic acid and similar color changes. The use of high electric field frequency did not affect the degradation kinetics of ascorbic acid and pigment compounds. This indicates that the ascorbic acid molecule predisposition for hydrogen donation in redox reactions was not affected by the rapidly varying electric field. (C) 2013 Elsevier Ltd. All rights reserved.