Influences of AC frequency and electric field strength on changes in bioactive compounds in Ohmic heating of pomelo juice

Ohmic Heating Extraction at Different Times, Temperatures, Voltages, and Frequencies: A New Energy-Saving Technique for Pineapple Core Valorization

“…Based on the response graph of S/N in the Taguchi method, the voltage was the most influential parameter in terms of heat generation. This is because an increase in voltage promotes the movement of electrons, resulting in higher heating rates [ 25 ]. According to Figure 2 , other independent parameters were less influential than voltage.…”

“…Further, the higher energy existing at high temperatures promotes electron movements, i.e., higher electrical current values are expected at higher electrical powers. Meanwhile, an increase in the frictional collision between the molecules may increase apparent resistance by considering the possibility of the leakage of plant cell ingredients [ 25 , 28 ]. A similar result appeared when phenolic compounds were extracted from wheat bran, showing that different voltage gradients (44 and 14 V/cm) can considerably enhance the heating rate and efficiency [ 29 ].…”

“…A suitable frequency can enhance the extraction while minimize the degradation of extracted compounds. As an example, it was reported that during pomelo juice ohmic pasteurization, TPC increased by 10%, depending on the electrical frequency applied [ 25 ].…”

“…Both tests show that the antioxidant activity increased by increasing frequency. As the antioxidant ability may increase by increasing the phenolic compounds, the oxidation of these compounds caused by the electrolysis reaction during ohmic heating extraction could be a reason for this observation [ 25 ]. At low frequencies, prolonged extraction times may provide suitable conditions for the electrode surface, ions, and electrolysis reaction.…”

“…Further, the higher energy existing at high temperatures promotes electron movements, i.e., higher electrical current values are expected at higher electrical powers. Meanwhile, an increase in the frictional collision between the molecules may increase apparent resistance by considering the possibility of the leakage of plant cell ingredients [25,28]. A…”