Optimization of Pre-Treatments to Overcome Stickiness-Related Hurdles and Enhance Drying Efficiency in Apple Pomace

Apple pomace (AP), a major by-product of apple juice processing, poses environmental and economic challenges because of its high moisture content, leading to storage difficulties and microbial degradation. Moreover, the high sugar content of AP contributes to stickiness during drying, which causes material agglomeration and limits efficient moisture removal-representing a significant hurdle in the drying process. Sustainable utilization of AP requires efficient drying methods to enhance its stability and usability. This study hypothesizes that enzymatic and ethanol pre-treatments can significantly improve the drying efficiency of AP by alleviating stickiness-related barriers. The objective was to optimize pre-treatment conditions to maximize moisture removal while potentially maintaining the quality of dried AP. Experiments were conducted using different ethanol concentrations, enzyme types (Pectinase, Cellulase), and treatment durations, with drying efficiency evaluated based on the removed moisture content (RMC) under various pre-treatment conditions. Under optimal conditions-combining Pectinase and Cellulase enzyme treatments with ethanol pre-treatment-the RMC increased from 12% (control) to 67%, representing a 5.5-fold improvement in drying efficiency. These findings demonstrate that optimized pre-treatments can effectively mitigate stickiness-induced drying hurdles, enhance AP drying efficiency, reduce waste, and support sustainable food processing. The proposed approach contributes to minimizing the environmental footprint of the apple processing industry. Future research should focus on scaling up these pre-treatment techniques and assessing their economic feasibility for industrial applications.