Effect of fast freezing then thaw-aging on meat quality attributes of lamb M. longissimus lumborum.

The objective of this study was to determine the effect of two different freezing rate then thaw-aging regimens on the quality attributes of lamb loins. The loins were randomly allocated to one of five different freezing/thawing/aging regimes: fast-(FF1A0) and slow-(SF1A0) frozen only; fast-(FF1A2) and slow-(SF1A2) frozen then thaw-aged for 14 days; aged for 14 days never frozen (A2). FF1A2 samples had a significantly higher water-holding capacity compared to the slow frozen regardless of further aging periods. FF1A2 samples had lower (p < 0.05) shear force values than A2 and higher (p < 0.05) water-holding capacity compared to the SF1A2. Fast freezing resulted in more intracellular cryo-damage, whereas slow freezing resulted in extracellular cryo-damage. FF1A0 and SF1A0 samples had lower (p < 0.05) myofibrillar proteins degradation. This study demonstrated that fast freezing then thaw-aging can result in an improved water-holding capacity and tenderness through the minimization of extracellular ice crystal formation, reduction in purge and drip losses, and improved proteolysis in thawed lamb.