Pork quality variation is not explained by glycolytic enzyme capacity

Area of Science:

• Meat Science
• Biochemistry
• Animal Science

Background:

• Pork quality traits, including color and water-holding capacity, are critical for consumer acceptance.
• Rapid glycolysis postmortem is linked to inferior pork quality, but the role of glycolytic enzyme capacity remains unclear.

Purpose of the Study:

• To investigate the relationship between the capacity of key glycolytic enzymes and pork quality attributes.
• To determine if increased enzyme capacity contributes to rapid glycolysis, leading to reduced meat quality.

Main Methods:

• Enzyme assays were used to quantify the total capacity of pyruvate kinase (PK) and phosphofructokinase (PFK) in longissimus muscle (LM).
• Muscle pH, purge, drip loss, and CIE L* color were measured in Duroc and Pietrain pigs harvested over two weeks.

Main Results:

• Pyruvate kinase (PK) capacity showed no correlation with LM pH, fluid loss, or CIE L* values.
• Phosphofructokinase (PFK) capacity was inversely related to fluid loss, suggesting a potential role in water-holding capacity.
• These findings indicate that increased capacity of these glycolytic enzymes is not directly associated with poorer pork color or water-holding capacity.

Conclusions:

• The capacity of glycolytic enzymes PK and PFK does not appear to be the primary driver of inferior pork color and water-holding capacity.
• Postmortem enzyme activity and potential denaturation, rather than enzyme capacity, may be more influential factors in meat quality.
• Further research should focus on enzyme kinetics and postmortem changes to fully elucidate their impact on pork quality.