Organic wastes are potential sources of both energy as well as crop production fertilizers. Correlations and models, involving organic matter characterization, have been previously described by several authors although there is still a lack in knowledge on the potential of simultaneous predictions of methane and organic fertilizer quality to optimize the wastes treatments. A methodology combining chemical accessibility and fluorescence spectroscopy was used to characterize 82 different organic wastes. Characterization data were compared with the biochemical methane potential (BMP), and with the biodegradable organic carbon obtained by soil incubation (C_bio). High correlations values were observed (R-2 of 0.818 for BMP and 0.845 for C_bio). Model coefficients highlighted the differences and similarities between anaerobic and aerobic soil biodegradation, suggesting that anaerobic recalcitrant molecules could enhance soil fertility. This is a first step in the development of a tool for optimising both types of valorisation according to agrosystem needs and constraints. (C) 2017 Elsevier Ltd. All rights reserved.