Carcass probe to underpin eating quality in lamb brands

AWSA National Conference Report - February 19, 2014

A new carcass probe with the potential to measure intra-muscular fat on-line in processing plants has the potential to underpin eating quality for Australian lamb brands.

Developed by Danish company Carometec, the probe uses electrical impedance, or current, to measure intramuscular fat in the eye muscle of a lamb carcass.

Meat & Livestock Australia, in conjunction with Murdoch University, will begin the first phase of testing the prototype device at Western Australia processing plant, WAMMCO, at Katanning, next week.

The Katanning trial is expected to be followed by full-scale calibration on resource flock animals in Western Australia.

Meat & Livestock Australia sheep research project manager Richard Apps said measurement technologies in processing plants was still one of the industry’s great stumbling blocks.

“When we think of something so simple as a fat score measurement on a lamb, how many plants are not doing that with any degree of accuracy,’’ Mr Apps said.

“We hope the probe will do it with reasonable accuracy and commercial line-speed application.

“It has the potential to measure intra-muscular fat on-line in the plant which will be a major step forward for us in underpinning high eating quality in brands for the lamb industry.’’

Mr Apps was a keynote speaker at the Australian White Suffolk Association conference in Hamilton this week.

He said significant data sets needed to be built on the probe before commercial release.

He anticipates the trial phase could take six months and is confident the probe will accurately measure tissue depth at the GR site (12th rib), and meat pH.
“The ability of the impedance capability to measure intramuscular fat is still a research question,’’ Mr Apps said.

“Unlike cattle, ultrasound scanning of live animals for IMF has not proven reliable for sheep; we think it is because the fat globules within the muscle tissue are much smaller.

“If successful, this probe will be a significant step in providing data for a really strong eating quality story, and will allow processors to grade lamb in many ways.

Victorian Department of Environment and Primary Industry lamb production research manager Dr Matthew Knight said intra-muscular fat (IMF) content related to the juiciness, flavour and tenderness of lamb.

Dr Knight said research had shown the ideal IMF range in lamb was 4-6 per cent, with crossbred lambs averaging 4.2 per cent for the Sheep CRC Information Nucleus lambs.

He said genetic research by the Sheep Co-operative Research Centre had shown IMF was moderately to highly heritable in sheep.

“If we breed sheep pushing for lean meat yield it has a negative affect on intra-muscular fat,’’ Dr Knight said.

He said tenderness may also be affected by on-farm handling, processing practices and cooking methods.

Sheep Genetics manager Hamish Chandler said the former LAMBPLAN Carcass Plus index had a significant negative impact on IMF, affecting shearforce.

Mr Chandler said the new Carcass Plus index was a “happy medium for fat, muscle and growth rates’’.

-Kim Woods

Commercial Register