Factors Influencing Tenderness In A Commercial Line Of Pigs

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Factors Influencing Tenderness In A Commercial
Line Of Pigs

• Phillip J. Rincker
• University of Illinois
• at Urbana-Champaign

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Why is it Important

• Currently there is a great deal of interest in
  identifying high quality products for branded,
  foodservice, or other specific markets.
• Some of the most common techniques involve
  marbling, pH, and color.

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• Historical research has focused on purebred pigs
  or crosses.
• It would be beneficial to understand how well
  typical meat quality traits predict sensory
  properties and shear force in a commercial line
  of mixed breed pigs.

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Study Design

• Use a population with known differences in
  tenderness.
• Control as many factors as possible
• Genetics (White line sows x Duroc sire).
• Management / Production Facility.
• Slaughter facility / date .
• Determine what contributes to the variation in
  tenderness values.

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Initial Data Collection

• pH measurements
• 45 minutes
• 3 hours
• 6 hours
• 48 hours

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pH Decline Data
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Typical Effects of pH Decline
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More Data Collection

• Typical quality measurements.
• Samples for PA and Histology.
• Age chops for either 2, 7, 14, or 21 days for
  shear force determination.
• Effect of pH?
• Effect of marbling?

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pH Decline and Quality
1Bold and italic items significant at P 11
Shear Force and pH
R20.05
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Shear Force and Lipid
R20.07
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Methods Part II

• Isolate loins with known differences in rate and
  extent of post mortem tenderization.
• Determine what contributes to the variation in
  tenderness.

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Average Aging Curves
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What Might Contribute?

• Few Quality Differences
• Collagen Content
• Sarcomere Length
• Protein Degradation

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Results
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Summary

• Measures of pork quality were quite variable.
• Single genotype, slaughter day/facility.
• Marbling
• Ultimate pH
• Color, WHC
• Sensory properties, shear force
• 50 did not tenderize post mortem
• Not explained by desmin degradation.

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Implications

• Typical measures of pork quality did not explain
  much variation.
• Unexpected differences in aging not explained by
  collagen or sarcomeres.
• Post mortem proteolysis of desmin does not ensure
  tenderization.

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Thank You

• Questions?