The quality of silage produced is dependent on the quality of material used in ensiling, temperature development during fermentation and type of fermentation. Good quality silage have a PH of 4.2, 1.5 to 2.5% lactic acid, 0.5 – 0.8 acetic acid and less than 0.1% butyric acid.
The DM content, the quality of fermentation and the feeding value of ensiled material all interact to determine the quality of silage.
Depending on DM content silage can be categorized as high DM content silage or low DM content silage. When water can easily be squeezed out of silage by hand the silage is said to be wet and has a DM content of less than 19%. When water cannot be squeezed out by hand silage is “dry” and has DM of over 26%.
Depending on the prevailing temperature silage can be classified as good quality silage as judged by physical characteristics like taste, smell, and color. Good quality silage has pleasant vinegar smell, an acidic taste and a firm soft texture, leaves not easily rubbed, light greenish or greenish brown in color.
Overheated silage has the smell of burnt sugar, dry texture, brown in color. Badly fermented silage has strong smell, offensive taste, slimy soft texture that can easily be rubbed from the fibre of leaf, bluish green in color.