Quality changes in apple juice as related to nonthermal processing

Fresh apple juice was preserved using ultrafiltration and high voltage puls ed electric fields as nonthermal preservation techniques. Changes in qualit y attributes such as soluble solids, pH, acidity, and color were verified f or both processes. Changes were tested in terms of membrane pore, transmemb rane pressure and recovery percentage for the ultrafiltration treatments, a s well as in terms of electric field strength and number of pulses for the pulsed electric fields experiments. Among the quality, attributes investiga ted, soluble solids, pH and acid content did not show significant differenc es, while color was significantly, different for both nonthermal techniques . For the ultrafiltered juice, a browning trend was observed, whereas for t he pulsed electric treated juice an opposite, lightening, tendency was pres ent.