Effect of method of analysis on iron content of beef from advanced meat recovery systems

A field survey was conducted by the USDA, Food Safety Inspection Service (FSIS) to provide analytical data on meat obtained from beef cervical vertebrae processed by advanced meat recovery (AMR) systems. As a result, an added iron performance standard was proposed to limit the amount of marrow in AMR products. The performance standard was based on iron content of hand boned lean compared to AMR lean. Iron content was determined by a hydrochloric wet ash digestion method. The same samples were then analyzed using dry ash digestion. The objectives of the study were to determine differences in iron content of the survey samples due to the digestion method and the impact of this difference on the added iron performance standard. Iron values by the dry ash method were approximately double those of the wet ash method. The difference was a result of incomplete volatilization of the organic matrix by hydrochloric acid in the wet ash procedure. The performance standards developed from the wet and dry ash methods were 1.8 and 3.2 mg added iron 100(-1) g, respectively. Added iron levels from the dry ash method greater than 3.2 mg 100(-1) g were present in 60% of the AMR lean indicating that some marrow was present or that factors other than amount of iron in hand boned lean should be considered before a performance standard is established.