Freezing and thawing or freezing, thawing, and aging effects on beef tenderness

Area of Science:

• Meat Science
• Food Science
• Animal Science

Background:

• Meat tenderness is a critical quality attribute influencing consumer acceptance.
• Understanding the impact of postmortem handling, including freezing and aging, on meat tenderness is essential for the beef industry.
• Previous research has not fully elucidated the combined effects of freezing, thawing, and aging on beef steak tenderness.

Purpose of the Study:

• To evaluate the effect of freezing and thawing, with or without subsequent aging, on the tenderness of longissimus lumborum (LL) and semitendinosus (ST) beef steaks.
• To compare the tenderness of processed steaks with aged, fresh steaks.
• To provide insights into optimizing meat processing and distribution for improved tenderness.

Main Methods:

• Beef steaks (LL and ST) from U.S. Select carcasses were subjected to various treatments: fresh aging, freeze-thaw, and freeze-thaw with extended aging.
• Steaks were frozen at -26°C for 30 days before thawing or thawing and aging at 2°C.
• Tenderness was assessed using slice shear force (SSF) and desmin degradation.

Main Results:

• Freezing and thawing alone or combined with aging significantly reduced SSF, indicating increased tenderness in both LL and ST muscles compared to fresh counterparts.
• Desmin degradation, a marker of aging and tenderness, was higher in steaks subjected to freeze-thaw with aging treatments.
• Cooking loss was comparable between some freeze-thaw-aged treatments and fresh steaks, suggesting minimal negative impact on this attribute.

Conclusions:

• Freezing and thawing, particularly when combined with aging, effectively enhances beef steak tenderness.
• These findings support the integration of freezing into commercial distribution to improve meat tenderness consistency.
• Researchers should account for the influence of freezing on tenderness when designing experiments.