Abstract
Certain chemical and physical characteristics of the gluteus medius and gluteus accessorius and gluteus profundus ham muscles were studied. The samples were secured from hams ranging in quality from a pale, soft, watery condition to a firm, dark, dry appearing tissue. The physical analyses included pH and expressible water, whereas, the chemical aspects included determinations of myoglobin, glycogen, sodium and potassium. Although some of the determinations were made on both the fresh and chilled tissue, the final ham muscle classification was made 24 hours after slaughter. The fresh tissues were not classified since the appearance differences were not detectable 2 minutes after slaughter. Likewise, there were no differences in muscle pH at slaughter time. Marked differentiation in muscle character appeared only after the reactions of anaerobic glycolysis had produced considerable acidity. The gluteus medius muscles of class I (pale-two-toned) possessed high initial glycogen concentrations, low ultimate pH values, high expressible water ratios and relatively high sodium concentrations. Conversely, the gluteus medius muscles of class IV (dark) were characterized by low initial glycogen concentrations, high ultimate pH values, and low expressible water ratios. Muscle color variations between the four muscle classes could only in part be associated with total myoglobin concentrations. The gluteus accessorius and gluteus profundus muscles were less variable in appearance and character than the gluteus medius muscles. Copyright © . .