Low frequency ultrasound treatment enhances antibrowning effect of ascorbic acid in fresh-cut potato slices.

Ascorbic acid (AsA) is generally used as an antibrowning agent for fresh-cut potato (FCP). However, its browning inhibitory effect is temporary because of its rapid consumption during redox processes. In this study, the effect of browning inhibition in FCP slices was evaluated using low frequency ultrasound (LFU; 40 kHz, 200 W, 3 min) and AsA (0.2%, w/v) treatments alone or in combination. The results showed that LFU combined with AsA (LFU-AsA) treatment could achieve a better antibrowning effect than either treatment alone (higher L*, lower a* and ΔE*), and there was no adverse effect on texture properties. LFU-AsA treatment not only inhibited the activity of PPO more effectively than AsA treatment, but also enhanced the antibrowning effect by retaining higher AsA content. Moreover, it also maintained membrane integrity by limiting lipid peroxidation and solute migration during storage. Overall, LFU-AsA treatment would be a promising method in food preservation industries.