INFLUENCE OF FREEZING/THAWING AND DRYING/MILLING ON BIOCHEMICAL METHANE POTENTIAL
In studies of biochemical methane production (BMP) researchers often collate a large number of samples at the same time for a
sample archive. The samples are often frozen to avoid microbial transformation, further homogenized by grinding. We studied
the influence of subfreezing/thawing and drying/milling of energy crop on BMP and anaerobic biodegradability (BD). Relative
standard deviation (RSD, %) between the BMP of controls and of the subfrozen was in the range 2.1–9.0%, and of the
dried/milled 3.1–17.5%. Whereas biodegradability of the controls was 72.3(±16.3)%, that of the pretreated was slightly lower at
70.5(±14.7)% for the subfrozen and 69.7(±18.4)% for the dried/milled.