Freezer Burn of Animal Tissue VI. Experiments With Ox Muscle Frozen Before and After Rigor

Abstract

SUMMARY—Freezer burn on bovine semitendinosus muscle from animals of good grade stored at ‐10°C and 78% RH was minimized by 24 hr of pre‐storage post‐mortem at 0°C, followed by slow freezing with permitted weight loss. Good‐quality beef was less likely to develop freezer burn of the muscle surface. To induce a definite intensity, muscle tissue from calf or canner‐grade cow required weight losses that were slightly lower, though the difference was statistically significant. Lapse of time after slaughter was examined in relation to total weight lost by the samples when specified intensities of freezer burn first became apparent. For samples frozen before or during the onset of rigor, or shortly after, this loss was almost twice as much as for samples frozen several days later.Histological examination showed that freezer burn in muscle tissue frozen prerigor frequently starts from intracellular cavities left by sublimation of ice crystals during desiccation. Intracellular desiccation produced a form of microburn. The occurrence of microburn was negligibly small in muscle chilled for 24 hr before freezing.