Water-evaporation-induced efficient high-temperature aerobic fermentation of food waste

Aerobic fermentation is an effective approach for reducing, stabilising, and recovering resources from food waste. However, its performance is often constrained by poor oxygen transfer within the fermentation substrate. In this study, we investigated how water evaporation promotes aerobic fermentation by altering the moisture distribution and pore structure of food waste. Water evaporation promotes the development of a thermophilic functional microbial community dominated by Bacillus bacteria and Diutina fungi, enabling efficient high-temperature aerobic fermentation of food waste. This process prolongs the thermophilic phase (+167%, p < 0.05) and increases the humic content (+18.82%, p < 0.05) and germination index (+41.39%, p < 0.05). Experimental results demonstrate that the water evaporation-induced moisture redistribution and pore structure improvement enhance oxygen transport within the food waste, thereby significantly improving the aerobic metabolism of organisms for proteins, polysaccharides, and lipids (p < 0.05). Metagenomic analysis confirms that water evaporation results in the enrichment of functional genes associated with the tricarboxylic acid cycle and electron transport respiratory chain in aerobic fermentation. These findings offer valuable insights for developing efficient aerobic biotechnologies for resource recovery from perishable organic solid waste.