CHANGES OF PHYSICAL-CHEMICAL PROPERTIES OF BEEF DURING 14 DAYS OF CHILLING

The objective of the work was to evaluate the effect of conditioning time (during 14 days of ageing at +4 o C) on physicochemical properties of two cattle skeletal muscles. Investigations were conducted on the m. longissimus dorsi (n=9) and m. gluteus medius (n=9) of Domestic Spotted breed. Muscle analyses were carried out 1 st , 7 th and 14 th day post mortem, during storage at +4 o C. Colour (CIE L*a*b* values, Hue and Chroma), cooking loss, shear force, water-holding capacity (WHC), pH value and sensory characteristics were determined in all meat samples. M. longissimus dorsi samples aged for 14 days were characterized by higher degree of lightness (L*) and chroma (C*) values, more of red colour (higher a*) and of yellow (higher b*), while m. gluteus medius colour changes during storage was not found to be significant. Over the 14 day conditioning period, tenderness (expressed as shear force) of the evaluated muscles improved significantly (p<0.05), it ranged from 11.50 kg/cm 2 (1 st day) to 5.00 kg/cm 2 (14 th day) for m. longissimus dorsi and from 9.81 kg/cm 2 (1 st day) to 5.10 kg/cm 2 (14 th day) for m. gluteus medius muscle. Cooking loss and WHC increased significantly over storage time (p<0.05) in both meat samples, while changes in pH values were insignificant. Sensory analyses revealed deterioration in flavour (smell and taste) and improvement in tenderness of roasted meat samples during storage.