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The ensiling of sugarcane results in high dry-matter ( DM) loss, but the addition of glycerine may compensate for the loss during ensiling. Methanol is the most undesirable contaminant of crude glycerine destined for animal feeding. The aim of this study was to evaluate the ability of the yeast strain Pichia methanolica NCYC 1381 to reduce the methanol concentration in sugarcane silage inoculated with Lactobacillus hilgardii CCMA 0170 + glycerine. A randomized design consisted of four dose rates of glycerine (0, 4, 8 and 12% of fresh forage), three periods of silage fermentation (11, 34 and 68 d) and three combinations of microbial additives [ L. hilgardii ( LH), L. hilgardii plus P. methanolica ( LH + PM) and without microbial additive ( WI)]. The DM of the fresh sugarcane was 275 g kg−1. The linear reduction in neutral detergent fibre caused by glycerine inclusion was probably due to a dilution effect. The LH treatment increased the concentrations of the succinic, acetic and propionic acids, and 1,2-propanediol, and reduced the yeast population. The LH + PM treatment increased DM loss of sugarcane silage with 12% glycerine and L. hilgardii CCMA 0170 (6·1 log cfu g−1 of FM) reduced the DM loss when compared to the silage without additives. Under the conditions of the experiment, the P. methanolica treatment did not reduce the methanol concentration in silage. [ABSTRACT FROM AUTHOR]

Aerobic stability is an important feature in the evaluation of silages. The aims were to investigate the chemical and microbiological changes that occur in sugar-cane ( Saccharum spp.) silage after aerobic exposure, to identify the major species of yeasts associated with the aerobic deterioration process and to select lactic acid bacteria ( LAB) strains that can improve the aerobic stability of this silage. Fourteen wild LAB strains belonging to Lactobacillus plantarum, L. brevis and L. hilgardii were evaluated using experimental silos. Silage samples were collected at 0, 96 and 216 h after aerobic exposure to determinate the DM, WSC, p H, products of fermentation, to evaluate the silage temperatures and to identify yeast species associated with the aerobic deterioration of silage. The strains tested were able to modify the fermentative and chemical parameters and the diversity of yeasts species of silage after aerobic exposure. There was no association between the facultative or obligatory heterofermentative fermentation patterns and the increased aerobic stability of silage. Aerobic stability of sugar-cane silages was associated with high acetic acid and 1,2-propanediol concentrations. L. hilgardii UFLA SIL51 and UFLA SIL52 strains promoted an increase in aerobic stability of silage. [ABSTRACT FROM AUTHOR]