Evaluation of The Effect of Hydrothermal Pretreatment on Food Waste for Bacterial Cellulose Fermentation Medium

Purpose Hydrothermal pretreatment stands out for its efficiency and simplicity yet offers economic and environmental benefits. Its application on non-fibrous organic waste such as food and fruit waste are deemed efficient and does not require extreme working parameters. This study evaluated the effect of predetermined parameters on the hydrothermal pretreatment of various food waste. We aimed to establish a set of parameters for the hydrothermal pretreatment, to promote the utilisation of waste for fermentation into value-added products. Methods The wastes were homogenized and treated at varying temperatures, incubation times, and water ratios. Reducing sugar, protein, and lipid content was analysed pre- and post-treatment. The treated waste was used as a medium for bacterial cellulose fermentation and the yield was compared to chemical medium. Results The models identified the best parameters for maximizing glucose production, achieving 443.202 mg/mL (KW), 421.453 mg/mL (GW), and 295.484 mg/mL (WW), with high desirability values for all samples. Attempts to produce BC from the treated waste recorded promising results. While KW had higher glucose content post-hydrothermal pretreatment, GW and WW produced more BC due to lower oil content, which did not interfere with the oxygen transfer. Conclusion The conducted hydrothermal pretreatment at the pre-optimized conditions increased the potential of FW as a media substitute for BC production.