Biotechnological potential of apple pomace for value-added products

Agri-food processing waste and by-products are important to be valued in an integral unit to the main process. This study focused on showing the potential valorization of apple pomace as substrate towards valuable products by a biotechnological mean. Apple pomace was fermented by B.subtilis at 37 °C, 150 rpm, and 72 h. Reducing sugars, total phenol content and α-amylase activity were followed throughout the fermentation. The results showed that B.subtilis assimilated apple pomace sugars and stimulated the release of sugars into the medium during fermentation. α-amylase activity detected in the medium also indicated the degradation of pomace by B. subtilis. However, the total phenol content was found to be low. The α-amylase activity at 24th h was 29.6% higher when the fermentation initiated with a former fermentation medium than that of started with the inoculum based on agar and liquid incubation media. Overall results showed –for the first time- that apple pomace can be valued towards α-amylase activity, reducing sugar and total phenol content by the activity of B.subtilis cells.