Digestates have been shown to have lower CH4 emissions than their relative untreated slurries (Amon et al., 2006), because the major part of the easily degradable matter has already been lost during the anaerobic digestion. At the same time, mixing has been shown to be an effective way to increase CO2 emissions, reducing the C-CH4/(C-CH4 + C-CO2) ratio (Blanes Vidal et al., 2012) and increasing slurry oxidation.