L.EQT.2107 Resource Flock MSA Mark II Limited Cut x Cook

Summary

In this project, the effect of ageing times on various cuts was explored. From 160 lambs and 40 yearlings, the right and left eye of rack, eye of shoulder, knuckle, loin, outside, rump and topside were collected and aged for either five, 14 or 21 days. The results demonstrate that eating quality can be improved after process-induced shortening through extended ageing and electrical stimulation.

Objectives

• Conduct sensory panels (n=60) with Australian untrained consumers as per the Meat Standards Australia (MSA) protocols, testing 108 lambs (Maternals, Terminals, Merino’s) and 36 shedding breed lambs (Dorpers) from the MLA Genetic Resource flock, and 36 hoggets (Merino’s) from a satellite flock.
• Gather additional information from the untrained consumer panel members such as simple demographic and willingness to pay information (as per the normal MSA protocols for sensory evaluation).
• Understand eating quality differences between lamb, hoggets and shedding breed lambs.
• Understand eating quality differences with respect to different ageing times (five, 14, 21 days).
• Provide the raw data for each session back to the Sheep Resource Flock Data.

Key findings

Key findings from this project include:

• Extended ageing to 14 or 21 days did improve lamb eating quality with little improvement beyond 14 days.
• Ageing of the eye of shoulder and topside to 14 or 21 days does not improve the overall liking compared to five days.
• Overall liking of the rump cut benefits from being aged to 21 days compared to five and 14 days.
• Temperature at pH 6 accounts for the differences between cuts across the ageing times.
• Dorper sired lambs produce the least acceptable meat, with Maternal, Merino and Terminal sired lamb cuts being of similar quality.
• At five, 14 and 21 days ageing, lamb sire type differences between Dorper lambs compared to Maternal, Merino and Terminal sired lambs are considered less acceptable.
• The eating quality of Merino yearlings is found to be less acceptable compared to Merino lambs, regardless of ageing time.

Benefits to industry

The data of this project will be incorporated into the MSA eating quality database where it will be utilised to inform the prediction of MSA graded products at a commercial level. In particular, it will deliver an expanded version of the MSA Mark II cut-based model for lamb with the inclusion of ageing time as a factor in the model.

MLA action

Final report publication. Further data analysis to expand the MSA Sheepmeat model was completed.

Future research

Future work can look at:

• The effect of loin residual glycogen on lamb eating quality of a variety of cuts.
• The impact of individual cut residual glycogen on lamb eating quality.
• Understanding factors accounting for differences in sire type eating quality: Dorper sired lambs vs. Maternal, Merino and Terminal sired lambs.
• Analysis to understand inclusion of Dorper sired lambs within the new developed MSA cut-based model.
• Analysis to understand impact of minimum MSA HSCW requirement in relation to pH outcomes and effect on ageing times.
• Impact of lambs versus yearlings within the new developed MSA cut-based model (with also the inclusion of older eating quality datasets including both animal groups).
• Impact of ASBVs on the ageing potential of the different lamb sire types.
• Development of maximum ageing times for cuts so that depreciation in eating quality due to ageing does not occur.