MSA carcase grading on the way for sheepmeat

The introduction of carcase grading to boost the predictive power of the Meat Standards Australia (MSA) sheepmeat program is in the pipeline, as researchers look to further enhance lamb’s eating quality.

The MSA sheepmeat program has experienced a significant increase in the number of sheep processed through MSA pathways. In 2017–18, more than 6.1 million sheep were processed through 19 MSA licensed abattoirs, representing 26% of the national lamb slaughter.

However, Murdoch University’s Professor Dave Pethick said there is significant scope to broaden the MSA sheepmeat program to further benefit all sections of the value chain, from producers through to consumers.

Professor Pethick was part of the initial MSA R&D Pathways team and heavily involved in establishing the MSA sheepmeat model. He remains a lead researcher in the area, and is now focusing on the establishment of a carcase grading system to measure lean meat yield and intramuscular fat.

Pathway to best practice

“Currently, MSA is a best practice pathways system for sheepmeat and in fact, much of the national lamb value chain follow MSA’s proven best practice guidelines,” Professor Pethick said.

“For sheep to be processed as MSA, you need a minimum carcase weight of 18kg and minimum fat score of 2.

“However, we know that one of the major drivers of eating quality in lamb is intramuscular fat, which is the equivalent of marbling in beef.

“If you could measure both lean meat yield and intramuscular fat at the abattoir, you could have additional predictive power in the MSA model.”

Importance of carcase grading

Professor Pethick said an analysis of LAMBPLAN genetic trends data from 2000 to 2017 shows that as lean meat yield has increased, intramuscular fat and consumer eating quality scores have decreased.

“That’s a clear sign that we need carcase grading. Lean meat yield is antagonistic to eating quality, but if we can measure them both, we can manage them and balance them,” Professor Pethick said.

“Carcase grading for factors associated with eating quality is on the way, as is a new cuts-based MSA lamb grading system.”

Professor Pethick said the grading system would enable lamb and sheepmeat to be graded and marketed as three, four or five star lamb.

“At the moment, all lamb is lamb, there’s no differentiation. Having a grading system would provide new branding and marketing opportunities,” Professor Pethick said.

Looking ahead

Professor Pethick said the technology for measuring lean meat yield is progressing rapidly.

“However, it is difficult to measure intramuscular fat at line speed in an abattoir. Manually grading by a human is not economically viable, so our research is focusing on getting a measure of intramuscular fat at line speed,” Professor Pethick said.

“We’re looking at a number of different technologies. One is by camera technology – we feel confident that it would work and hopefully will be available for abattoirs next year, but it would be taking measurements close to the boning room given the camera technology will be imaging a cut surface of a ‘cold’ carcase.

“Other options still in progress include using near infrared (NIR) technology and we have engaged a company from Japan who use the technology to measure fat content in tuna. That technology is coming to Australia for testing later this year.”

Professor Pethick said while he’s focused on getting the carcase grading system for sheepmeat working in abattoirs, he believed the introduction of a new formal yearling category for sheepmeat would further expand marketing options.

“It could be a category for people who want to sell a non-lamb product, but that would be radical in the sheep industry because lamb has such a strong name,” Professor Pethick said. 

“Australian lamb is a brand in its own right and is recognised as a great product around the world.”