Cattle manure usually contains a proportion of carbohydrates in the form of organic
residues from incompletely digested feed and farm husbandry practices. These are not usually
available for biogas production due to the long fermentation time. This paper investigates the optimal
application of alkali, NaOH and KOH and mechanical pre-treatments to improve the degradation
of the lignocellulosic content and the potential biogas yields from a local farm in Bavaria, Germany.
Parameters such as temperature, pH, soluble chemical oxygen demand, organic acids, dry matter and
volatile solids were analysed for this purpose. Alkali pre-treatments in 0.2, 0.1 and 0.05 M NaOH con-
centrations were tested in single mode and combined with shredding in batch experiments. The max-
imum increment of the soluble chemical oxygen demand during the pre-treatments took place during
the first 50 h of experimentation, and it showed an improvement of 10,060.0 ± 8% mg/L s COD after
the application of 0.2 M NaOH compared to the untreated substrate, which had an initial value
of 2145.0 ± 8% mg/L s COD. Pre-treatments with 0.1 and 0.05 M NaOH concentrations showed sim-
ilar s COD increments, with an additional 6860.0 ± 8% mg/L s COD and 8505.0 ± 8% mg/L s COD,
respectively. The pH values varied strongly after the addition of the pre-treatment chemicals, with a
continuous pH of 12 by 0.2 M NaOH during the 7 days of pre-treatment. Batch biogas experiments
were done by applying 0.05 M NaOH and 0.05 M KOH pre-treatments in single mode and combined
with shredding. The chemically pre-treated substrates showed a faster biogas production with an
advantage of 18 days in comparison to the untreated cattle manure by a biogas yield of 350.0 NL/kg
VS. All experiments were done under mesophilic conditions.