Citric acid metabolism in the bovine rumen.

Rumen microorganisms rapidly metabolize citric acid to carbon dioxide and acetic acid. The rate of metabolism varied between 0.00008 and 0.76 mumoles per g per min, the rate becoming higher as the citric acid concentration increased. The addition of potassium chloride to rumen contents decreased the rate of utilization. The results indicate that dietary citric acid is unlikely to accumulate in the rumen to a sufficiently high level to be an important factor in hypomagnesemia, except where other factors such as very high potassium levels in the food influence its metabolism.