Chemical composition and production of ethanol and other volatile organic compounds in sugarcane silage treated with chemical and microbial additives

Abstract

Sugarcane silage can be used in animal production systems; however, it is important to apply additives to improve its chemical composition and fermentative quality. We evaluated the effect of chemical (urea and calcium oxide (CaO)) and microbial (Lactobacillus buchneri (LB), Lactobacillus plantarum, Pediococcus pentosaceus, and Propionibacterium acidipropionici) additives on chemical composition, fermentation profile, microorganism population, and production of ethanol and other volatile organic compounds in sugarcane silage. Treatments studied were silage without inoculant (SS), SS with LB, SS with Lactobacillus plantarum and Pediococcus pentosaceus, SS with Lactobacillus plantarum and Propionibacterium acidipropionici, SS with 5 g CaO/kg fresh material (FM) (5CaO), SS with 10 g CaO/kg FM (10CaO), SS with 5 g urea/kg FM (5urea), and SS with 10 g urea/kg FM (10urea). The highest crude protein content (P = 0.001) and the lowest N-linked to fibre content (P = 0.001) occurred when applying urea. None of the treatments reduced the presence of yeast (P = 0.054), but a trend was detected of treatments based on CaO as promising in this Control. The silages treated with CaO had lower ethyl ester and ethanol (average for CaO-based treatments of 0.012 g/kg dry matter and 0.695 g/kg dry matter, respectively), and silages treated with 10urea had less acetone (P = 0.001) and methanol (P = 0.001). The sugarcane silages treated with chemical additive CaO reduced ethanol production and ester formation. There was a high correlation (r = 0.984) between ethyl acetate + ethyl lactate and ethanol contents.