In a Poultry Science paper, M.W. Schilling of Mississippi State University and co-authors there and at Johnsonville Sausage LLC, University of Arkansas and O.K. Industries report research they conducted to determine the effects of stunning method (low atmosphere pressure, LAPS, and electrical stunning, ES) and deboning time (0.75 and 4.0 hours) on breast meat quality (n=576, 144 birds per treatment) in a commercial processing plant.

Breast meat quality was evaluated through determining pH, Commission Internationale d’Eclairage L*a*b*, cooking yield, shear force and consumer acceptability.

The onset of rigor mortis was more rapid (P<0.05) in breast meat from LAPS-stunned birds than ES-stunned birds but no differences existed (P>0.05) among stunning methods with respect to final pH at 24 hours.

As expected, breast meat that was deboned at four hours required less shear force (P<0.05) to cut through the breast than samples that were deboned at 0.75 hours post-mortem but no differences existed between breast meat from LAPS or ES broilers that were deboned at the same time post-mortem.

However, when samples were marinated with 2.0 per cent sodium chloride and 0.5 per cent phosphate, there was no difference in Allo-Kramer shear force between ES four-hour and LAPS four-hour samples but the ES 0.75-hour samples had lower shear force values (P<0.05) than the LAPS 0.75-hour samples.

On average, the LAPS four-hour treatment had greater overall acceptability ratings (P<0.05) than other treatments and the ES and LAPS four-hour treatments had more acceptable (P<0.05) texture than the ES and LAPS 0.75-hour treatments.

Cluster analysis revealed that the two largest consumer groups liked all chicken breast fillet treatments but a larger proportion of consumers liked the four-hour LAPS and ES treatments than the 0.75-hour LAPS and ES treatments.

In addition, consumers who rated baked chicken breast as at least moderately acceptable preferred (P<0.05) the four-hour LAPS samples over the four-hour ES samples.

Schilling and co-authors concluded their study revealed that both the stunning systems can be successfully used in commercial poultry plants without detrimental breast fillet quality problems with respect to colour, texture and consumer acceptance.

Reference

Schilling M.W., V. Radhakrishnan, Y. Vizzier-Thaxton, K. Christensen, P. Joseph, J.B. Williams and T.B. Schmidt. 2012. Effects of low atmosphere stunning and deboning time on broiler breast meat quality. Poult. Sci. 91(12):3214-3222. doi: 10.3382/ps.2012-02266

You can view the full report (fee payable) by clicking here.

February 2013