Effects of alternating electric field during freezing and thawing on beef quality.

Alternating electric field (AEF) technology was used during freezing-thawing-aging (FA) of beef aged for 0, 1, 3, 5 and 7 days. Color, lipid oxidation, purge loss, cooking loss, tenderness, and T relaxation time were determined for frozen-thawed-aged beef with AEF (AEF + FA) or without AEF (FA) and compared to aged only (OA) controls. FA increased purge loss, cooking loss, shear force values and lipid oxidation (P < 0.05) but decreased a* values compared with AEF + FA treatment. It also exacerbated the spaces between muscle fibers and contributed to the transformation of immobile water to free water. AEF served to maintain meat quality by reducing purge loss, cooking loss and increasing meat tenderness and maintaining color and lipid oxidation only in steak that was frozen before aging. This most likely occurred due to AEF increasing the speed of freezing and thawing and by reducing the space between muscle fibers compared to FA alone.