AI Meets Citrus Waste: Coffee Bean Processing with Orange Peel Flour

Orange peel represents 50% of the fruit, and more than 124 million tons are consumed worldwide, which represents a worrying contamination problem. This study sought to add this waste as flour in coffee fermentation to enhance the process. Since this is a new alternative in the processing of coffee beans, the study focused on modelling the reducing sugars of coffee fermentation by adding citrus waste to relate artificial intelligence to the practical application of using waste in production processes. Standardised analyses were performed regarding pH (4.86 ± 0.05), humidity (8.17 ± 0.74%), ash content (4 ± 0.03%), and reducing sugars (20.23 ± 0.20 mg/mL), and orange peel flour was added to coffee beans at concentrations of 0, 2, 4, and 6% for solid-state fermentation. The results indicate that the 2% concentration accelerated fermentation times, increased reducing sugars, and maintained favourable sensory qualities in the coffee (flavour profile of delicate fruity and floral notes). Artificial neural networks revealed a strong overall correlation (R2 = 0.866) between pH changes and sugar concentrations throughout the process. This research highlights the potential of utilizing orange peel flour to enhance coffee fermentation, supporting further investigation into their application across various stages of coffee processing to maximise overall quality and environmental benefits.