3.1.2. TC/TN and DC/DN
C/N ratio is traditionally used to evaluate the maturity degree of
compost (Bernal et al., 1998). Previous research showed that a C/N
ratio below 20 was assumed to be indicative of maturity compost
(Golueke, 1981). Fig. 2 shows TC/TN and DC/DN changes during
composting. TC/TN ratio decreased from 27.3 at 0 h to 18.0 at
96 h in DHAF, while it decreased from 27.4 at 0 d to 19.7 at 24 d
in TSC. The results were kept in accordance with previous studies.
Dissolved organic carbon and nitrogen are direct nutrient feed
microorganisms, which also can be used as an indicator for maturity.
DC/DN ratio decreased from 36.3 at 0 h to 6.8 at 96 h in DHAF,
while it decreased from 32.3 at 0 d to 7.8 at 24 d in TSC. The results
showed that food waste was mature after 96 h of fermentation in
DHAF and 24 d of composting in TSC.