Evaluation of colour and bleeding efficiency of imperfectly bled, scientifically slaughtered and cold slaughtered beef carcasses

Abstract

The present study was carried out at the Meat Technology Unit, Kerala Veterinary and Animal Sciences University, Mannuthy to examine the colour and bleeding efficiency of beef carcasses subjected to varying levels of bleeding. Muscle samples were collected from imperfectly bled (IB), scientifically slaughtered (SS) and cold slaughtered (CS) beef carcasses and were packed in HDPE packages. The Hunter L* a* b* values were analysed on the 0,2,4 and 6 days of refrigerated storage at 4±1◦C and the bleeding efficiency was studied on the day of slaughter. From the results it was concluded that malachite green test (MGT) could be assigned as a test to detect complete bleeding. However only lower proportions of IB and CS samples showed positive results on MGT assay, which makes it a less reliable method for detecting the efficiency of bleeding. The mean haemoglobin (Hb) concentration (mg/g) of IB and CS carcasses (0.07±0.003 and 0.09±0.008, respectively) were significantly (p˂0.01) higher than that from SS carcasses (0.05±0.004). There was no significant difference between IB and SS groups for the blood loss parameters considered. The mean number of turgid intercostal veins for IB (7.83±0.98), SS carcasses (6.5±0.88) was significantly (p˂0.01) lower to that of CS carcasses (10.5±0.43). More than 10 turgid intercostal veins in a bovine carcass may be indicative of cold slaughter and absence of bleeding. No significant difference was noted between groups on all days for a* value and on all days except day 2 for L* and b* values.