MICROBIAL FERMENTATION OF CEREAL-GRAINS IN-VITRO

The stoichiometry of fermentation was investigated in vitro with wheat and maize grains. Gas production proved to be an accurate index of VFA production and change in pH. Gas and total VFA production from wheat were strongly correlated with starch disappearance. On a stoichiometric basis, 66% of gas and 64% of VFAs produced from wheat were accounted for by starch fermentation. With maize only 18% of gas and 23% of VFAs produced were accounted for by starch disappearance. There were significant differences between grain species in rates of gas production (P < 0.001), being ranked in the order wheat > triticale, oats > barley > maize > rice, sorghum. Effects of varieties and growing sites on gas production were significant with wheat, oats, maize and sorghum. With barley, only varietal effects were significant (P < 0.001). With maize and sorghum, there were significant variety by site interactions.