Effects on methane production
Following the compositional analysis, laboratory fermentation experiments were conducted
to link grape marc composition with ability to reduce methane production. Results showed
that tannin concentration, tannin composition and overall fatty acid content were the most
important factors influencing methane reductions.
Steam distilled red marc and ensiled white marc parcels were then selected for feeding trials
with dairy cattle. Further trials with sheep are planned to take place at the University of
Melbourne in 2014/2015, investigating two different dose rates of grape marc. Results from
these animal trials will be published at the conclusion of the project.