Date of Award
Master of Science
Food Science and Technology
Grayce E. Goertz, Mary J. Hitchcock
The effect of the temperature of meat when cores were removed and the temperature of the cores at the time of shearing on Warner-Bratzler shear values was studied. The precision of measurements obtained with the Warner-Bratzler shear device as affected by a combination of these temperatures was estimated. Beef roasts from the biceps femoris muscle were cooked at 300o to an internal temperature of 170oF. Four temperature combinations were tested: (1) samples cored and sheared at 150oF; (2) samples cored at 150oF, and sheared at room temperature; (3) samples cored and sheared at 40oF; and (4) samples cored at 40oF, and sheared at room temperature. A total of 733 shears on 192 cores from 12 roasts obtained from three steers was evaluated.
Only a slight difference in shear values was associated with the two coring temperatures (P < .10); however, there was a difference (P < .01) associated with the three shearing temperatures. Samples sheard at 150oF yielded lower average values than were obtained by shearing at room temperature or at 40oF.
A high degree of variability in shear values was obtained with all temperature combinations. However, the values for samples cored and sheared at the coolest temperature, 40oF, had the lowest coefficient of variation, 32.3%. Thus, it appeared that the precision of the measurements obtained with the Warner-Bratzler shear apparatus was affected by the temperature of meat samples at the time the cores were removed and sheared.
Fields, Elizabeth Smith, "The Relation of Beef Temperatures During Coring and Shearing to Warner-Bratzler Shear Values. " Master's Thesis, University of Tennessee, 1970.