“Will oxygen scavenging antioxidants help make up for loose packing?“
Air is the worst enemy of silage production. In theory, you could add antioxidants to “mop” this up, but the amount required to achieve even distribution and scavenge all the available oxygen would be impractical. In reality, there is no additive that can make up for poor packing or covering.
There is always some air (oxygen) remaining in the silage environment immediately after it is put into storage. Until plant cells are dead or have no oxygen available, they respire. This process generates heat. Oxygen also allows aerobic microorganisms such as yeasts, bacilli and molds to grow and produce carbon dioxide, water and more heat. This further increases the temperature of the ensiled crop.
Packing the silo, bunker or pile efficiently will help exclude and drive oxygen out, which limits the growth of aerobic spoilage microorganisms. This is also why experts recommend keeping silage covered and maintaining a tidy feedout face.
One thing that does provide an assist are some lactic acid bacteria (LAB), which will grow aerobically as well as anaerobically. As these LAB grow, they scavenge oxygen from the plant mass, producing about half as much lactic acid as they do in an anaerobic environment. Therefore, LAB can help get rid of the trapped oxygen and, at the same time, begin the pH drop needed to efficiently ferment silage.
Using a research-proven inoculant with sufficient numbers of selected LAB can help ensure silage pH drops rapidly and help prevent the growth of yeasts and clostridial fermentation. Other methods — like using a chemical oxygen scavenger — are unrealistic.
I hope this information helps you create high quality silage.
The Silage Dr.