Summary: | The aim of this study was to investigate the interaction between different rates of freezing and thawing on whole ostrich moon steaks to establish a combination or singular main effect that minimises thaw loss and maximises the retail display shelf-life regarding moisture loss, colour, lipid oxidation and tenderness. Five characteristic freezing rates (FR: 1, 2, 4, 8, 24 h) were compared with five characteristic thawing rates (TR: 1.5, 3, 6.5, 14, 21 h) in a completely randomised block design. Moon steaks (<i>M. femorotibialis medius</i>) from 125 birds were randomly assigned to a specific treatment combination before being subjected (after thawing) to a 10-day chilled storage at 4 °C shelf-life trial. Thawing rate had no effect (<i>p</i> > 0.05) on any of the quality (colour, drip and cooking losses, shear force, 2-thiobarbituric acid (TBARS)) parameters whilst freezing rate and display time both had significant (<i>p</i> < 0.05) influences. Thaw loss was lowest (<i>p</i> < 0.05) for the FR_1h and FR_2h, followed by FR_4h, FR_8h and FR_24. The FR_1h had the highest (<i>p</i> < 0.05) drip and shear force values during display while the FR_2h and FR_8h had the highest rate of oxidation (TBARS and metmyoglobin formation). FR_24h had the second best (<i>p</i> < 0.05) colour retention after FR_4h and minimal package drip. Overall, FR_4h resulted in the best quality meat over the entire shelf-life with high bloom retention, low TBARS and shear force, and average thaw, drip and cooking loss.
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