MSA Index

The MSA index is a single number and standard national measure of the predicted eating quality and potential merit of a carcase.

The MSA index is a number between 30-80, expressed to 2 decimal places (ie 54.62), to represent the eating quality potential of a whole carcase. The MSA index is independent of any processing inputs and is calculated using only attributes influenced by pre-slaughter production. It is a consistent benchmark which can be used across all processors, geographic regions, and over time. It reflects the impact on eating quality of management, environmental and genetic differences between cattle at the point of slaughter.

Why is the MSA index useful?

Producers are able to access MSA feedback for individual carcase traits including carcase weight, rib fat, MSA marble score, ossification score, HGP status, hump height and sex. However it is difficult to assess the importance of these individual traits on eating quality and how changes in breeding and genetics or management decisions impact on the eating quality of the carcase. The MSA index combines the impact of all these inputs and allows producers to evaluate changes in their business, to drive a faster rate of gain in eating quality.

With the goal to improve eating quality for the consumer, the producer and lot feeder are faced with how to economically improve eating quality and the MSA index through genetics and management interventions. 

How is the MSA index calculated?

The MSA Model predicts the eating quality of 39 cuts in a carcase using the measurements collected by accredited MSA graders. 

MSA eating quality scores are the combination of tenderness, juiciness, flavour and overall liking of beef. The MSA index is a weighted average of these scores for the 39 MSA cuts for the most common corresponding cooking method. It is not a yield measurement. 

The MSA index is a tool to be used by producers and lot feeders. Inputs in the MSA model controlled by the processor, for example, hang method, days aged, ultimate pH (within the acceptable range), and loin temperature are set as default values. The MSA index is calculated for achilles hung carcases with 5 days ageing. 

A carcase with a higher MSA index will have higher beef eating quality scores for many cuts compared to a lower MSA index carcase. The changes in eating quality of individual muscles will depend upon the different combinations of carcase inputs affecting cuts in different ways. This is why the MSA index is a measure of the average eating quality of the whole carcase.