Biodegradation of milk when applied to soil

Abstract

Degradation rates of milk applied to soils were not influenced by soil type, but were significantly affected by temperature. Of the major substrates present in added milk, the milk lipids were the most resistant to decomposition. Lipase production by the soil microflora coincided with lipid hydrolysis. Reapplication of more milk to the same soil resulted in a more rapid respiratory response and lipid degradation. When milk fats alone were applied to soil, their hydrolysis was much slower than when the equivalent fat concentration had been applied as milk. The significance of the findings in relation to suggested procedures for emergency land disposal of milk is discussed.

Keywords:

• milk
• milk constituents
• wastes
• waste disposal
• biodegradation
• soil temperature
• soil microflora
• soil bacteria
• soil fungi
• soil respiration
• lipid hydrolysis