Technological watch

The degree of anaerobiosis and its maintenance over the conservation period are key factors in obtaining high quality silage. There is currently a demand to replace petroleum-based plastic films with biodegradable materials with suitable mechanical properties. This work has evaluated, under outdoor conditions, the shelf life of a Mater-Bi® biodegradable plastic (MB) film and its effects on the fermentative characteristics, microbial counts and aerobic stability of corn silage, and compared it with commercially available polyethylene (PE) and high oxygen barrier (OB) films. Corn (409 g DM/kg) was ensiled in 30 drive-over piles covered with MB, PE or OB films. The piles were opened after 21, 85, 133, 195 and 230 d of conservation. The effect of the film was assessed in silage sample close to (CF) and far (FF) from the film. The OB film allowed high quality corn silages to be obtained with similar pH, lactic acid, yeast and mold counts for CF and FF during the entire 230 d of conservation. The PE film showed similar values for the FF and CF areas for the first conservation period (until 133 d). The MB film showed a similar silage quality to OB until day 85, after which it underwent biodegradation and lost its ability to preserve silage in a good state.