Development Proposal for VOS Marbling Probe (Proof-of-Concept)

Summary

There is increasing emphasis to measure and grade the hot carcase. Whilst marbling can be measured using both subjective and objective methodologies on the cold carcase, measurement on the hot carcase provides a challenge as the fat has not solidified and is not visible. The technique known as velocity of sound (VOS) provided a possible technique by which to measure marbling objectively on both the cold and hot carcase.  
A hand-held ultrasound penetration probe was constructed for VOS testing of beef samples in laboratory conditions. VOS measurements at 30 degree C predicted intramuscular fat with a residual standard deviation of 2.4% fat (r=0.85). The predictive value of VOS was better at 30 degree C that the two lower temperatures, 15 degree C and 2 degree C, tested.
The measuring equipment for VOS consisted of an adjustable, U-shaped callipers like device, the free extremities of which housed a transmitting and a receiving transducer opposite each other and directly in line. The precision of alignment and the rigidity of the clamp were critical for the accuracy of measurements. Upon initiation, the electronic system automatically measured the time that a pulse of ultrasound took to travel through the carcase from one transducer to the other and determined the inter-transducer distance.  It then computed and displayed the speed of transmission.
This research developed and evaluated a prototype unit for measuring meat quality traits including marbling using Velocity of Sound Technology.  The proof-of-concept prototype VOS device could then be developed to the next stage, incorporating multiple transducers, a temperature sensor and real-time processing/display of the result.  VOS therefore provides a possible tool to objectively measure marbling in both the cold and hot carcase.