Produces a rancid butter smell and taste. Elevated levels indicate silage deterioration from secondary fermentation, which in the presence of unpalatable nitrogenous end products such as amines and amides, may lead to significant reduction in dry matter intake and energy level of the forage. Butyric acid and nitrogenous proteolysis is the result of Clostridial activity in the silo. Yeast converts sugars to alcohol and may metabolize lactic acid, which will raise pH and lead to unstable silage. The presence of ethanol is more prevalent in high moisture corn and corn silage.
Aerobic microorganisms require oxygen from air penetration, indicating aerobic instability.
Counts less than 100,000 are desirable. Yeast utilizes lactic acid as substrate in the presence of oxygen, causing the elevation of pH. Dry matter losses occur from the production of carbon dioxide, water, and heat. Yeast activity precedes mold growth. Counts less than 100,000 are desirable. This results in musty, hot, energy depleted, and unpalatable silage.