Effects of potassium sorbate and sodium benzoate at two application rates on fermentation and aerobic stability of maize silage

Abstract

This study evaluated two potassium sorbate (PS) and sodium benzoate (SB) application rates in improving the aerobic stability of maize silage. Treatments included no additive, the addition of PS at 1 and2 g kg-1 fresh matter (FM) and the addition of SB at 1 and 2 g kg-1FM. Four replicates of each treatment were ensiled in 15-L plastic jars. The silages were analysed for their fermentative characteristics and were subjected to an aerobic stability test with pH and yeast and mould count measurements. Considering fermentation quality and aerobic stability, both additives were effective. The PS was more active against yeasts during aerobic exposure. When the additives were applied at 2 g kg-1, the silages were more stable (256 h, on average) than those with 1 g kg-1 (119 h, on average) and control (61 h). Aerobic deterioration was more pronounced in the controls than in the treated silages. Silages treated at 2 g kg-1had consistent effects on pH values and yeast counts over 288 h of aerobiosis. Overall, PS and SB applied at 2 g kg-1 were more effective in improving aerobic stability.