Chemical composition determines the bioenergy potential of food waste from pre- and post-production

The chemical characterization of the food waste allowed to discriminate between the pre-preparation and post-preparation residues from a restaurant. Carbohydrate-rich or lignin-rich waste can be identified and a better use prosed. Based on this characterization, the potential of energy production regarding methane generation capacity was estimated, analyzing the chemical composition and characteristics of the residues in a case study in Brazil. The analysis showed 87% of moisture content, 7.5% of ash, 53% of extractives, 22% of carbohydrates, and 21% of non-carbohydrates. Samples contained residue of beet, carrot, cabbage, and squash presented 52% carbohydrate content and, consequently, a great potential for biogas generation. Samples containing residues of cucumber, banana, chayote, and white beans presented 35% of non-carbohydrates (lignin) content, indicating its potential use in the co-generation of energy. The results indicated that the waste generated in the food industry represents an important potential for energy generation, and its best use can be determined by the biomass chemical composition.