Alcoholic fermentation and its prevention by Lactobacillus buchneri in whole crop rice silage

Aims: To evaluate the fermentation characteristics and the effects of Lactobacillus buchneri inoculation in ensiling whole crop rice. Methods and Results: Laboratory-scale silages were prepared from whole crop rice harvested at yellow-ripe stage. The crop was ensiled for 2 months with and without inoculation of L. buchneri at 10⁴, 10⁵ and 10⁶ CFU g^-1. The effect of prolonged ensiling was also studied by using the same crop; the silos were opened at 1, 3, 6 and 12 months, while the inoculation was made at 10⁵ CFU g^-1. Enhanced alcoholic fermentation was found in untreated silage; the sum of ethanol and 2,3-butanediol were seven times higher at 2 months than those of lactic and volatile fatty acids, while the differences were diminished at 12 months owing to the reduction of ethanol in the late ensiling period. Inoculation of L. buchneri inhibited the alcohols; however, ethanol yet prevailed over the fermentation until 6 months, after which acetic acid became the main product in the inoculated silage. Regardless of inoculation and ensiling period, yeasts were not found in whole crop rice silage. Conclusions: Substantial amounts of ethanol and 2,3-butanediol would be produced in silage prepared from whole crop rice. The alcoholic fermentation can be suppressed when inoculated with L. buchneri. Significance and Impact of the Study: Inoculation of L. buchneri could be an option to prevent ethanol fermentation in silage.