A preliminary investigation of the effects of frozen storage on samples of pork

The effects of combinations of freezing, thawing and frozen storage on the drip loss and ultrastructure of small samples (approximately 6 g) of pork were studied. Samples were stored for up to 12 weeks at -20 degrees C or for up to 4 weeks at temperatures fluctuating between -10 and -3 degrees C. Drip was collected by centrifugal extraction. Cryo-scanning electron microscopy was used to study the ultrastructure of the meat. Sizes of cavities created after sublimation of the ice crystals were quantitatively analysed using an image analysis software package. Freezing rate by storage time interactions were observed in drip loss analyses. No differences were observed in the drip protein concentration or electrophoretic patterns. Ultrastructural differences were only observed after thawing samples stored at the higher temperatures. The effects being investigated were subtle. (C) 1999 Elsevier Science Ltd. All rights reserved.