Haemoglobin concentrations in beef

Haemoglobin was used as an index of residual blood in beef muscles from various sources. Factors determining the amount of residual blood appear to operate in a similar way throughout the carcass musculature. Only one in 60 samples of M. longissimus thoracis et lumborum showed any evidence of poor bleeding and the increased blood content was very small. M. psoas major from cows and bulls contained significantly higher amounts of haemoglobin than those from steers, and in the case of cows this appeared to be due to their greater age, more blood being retained in the muscles of older animals. It is estimated that between 1.1 and 4.3% of the total blood volume of the live animal is retained in the musculature of a normal steer carcass and that the average residual blood content of normal butcher 's meat is about 0.3%.