Relationship of texture profile analysis and Warner-Bratzler shear force with sensory characteristics of beef rib steaks

Abstract

Cyclical texture profile analysis (TPA) parameters measured using a star-shaped probe with two cycles of 80% penetration and Warner-Bratzler shear force (WBS) were compared as predictors of objective tenderness and subjective sensory characteristics of rib steaks from 52 beef loins. The TPA parameters of hardness, cohesiveness and chewiness were negatively correlated (P<0.05) with trained panel sensory characteristics of initial tenderness (r=−0.64, −0.41, −0.62, respectively), amount of connective tissue (r=−0.57, −0.27, −0.55, respectively), overall tenderness (r=−0.68, −0.39, −0.64, respectively) and overall palatability (r=−0.56, −0.37, −0.53, respectively). These sensory characteristics were also negatively correlated (P<0.05) with WBS (r=−0.61, −0.49, −0.60, −0.56, respectively). Stepwise regression analysis generated prediction equations that included the TPA parameters of hardness and adhesiveness, which accounted for 47, 36, 51 and 38% of the variation in initial tenderness, amount of connective tissue, overall tenderness and overall palatability, respectively. Prediction equations using WBS accounted for 37, 24, 36 and 31% of the variation in initial tenderness, amount of connective tissue, overall tenderness and overall palatability, respectively. Hence, TPA explained more of the variation in subjective sensory tenderness of the rib steaks than WBS.

Introduction

Human perception of meat palatability is derived from a complex interaction of sensory and physical processes during chewing. Of the various subjective characteristics determining meat palatability, tenderness is the most important (Jeremiah, 1982).

Several objective methods of predicting meat tenderness have been developed, however these usually rely on measuring a single parameter and none fully imitate the complexity of the chewing motion (Bouton & Harris, 1972, Pearson, 1963, Szczesniak & Torgeson, 1965). Recognizing this limitation, the mechanical process of mastication has been simulated using texture profile analysis (TPA). This objective method measures the compression force of a probe and the related textural parameters of a test food during two cycles of deformation. The TPA of various foodstuffs including fruits, vegetables, bakery and meat products have been reported (Penfield & Campbell, 1990). The range in variation of subjective sensory characteristics of beef tenderness determined by sensory panels, explained by the objective textural parameters of TPA varies from 3 to 85% (Szczesniak, 1968). Rhodes, Jones, Chrystall, and Harries (1972) used stepwise regression to rank the relationship between various textural parameters of roast beef determined from the force-deformation curves of an instrumental compression device as compared to that of trained panelist ratings for tenderness and juiciness. All together the instrument textural parameters accounted for about 50 and 30% of the sensory-variability for tenderness and juiciness characteristics of warm roast beef, respectively.

Warner-Bratzler shear force (WBS) is an imprecise predictor of beef tenderness characteristics determined by trained panelists (Shackelford et al., 1995, Shackelford et al., 1997). Correlations of WBS with sensory assessment of beef tenderness have been variable, ranging from −0.60 to −0.85 (Pearson, 1963) and −0.32 to −0.94 (Szczesniak, 1968). In spite of the 10–89% range of variation reported in the aforementioned studies, mean values of −0.75 (Pearson, 1963) and −0.77 (Shackelford, Wheeler, & Koohmaraie, 1999) suggest that WBS explains a substantial proportion of variation in sensory assessment of beef tenderness. Consequently, WBS has become the most common objective method for evaluating beef tenderness (Boleman et al., 1997, Miller et al., 1995).

Previous reports indicate TPA and WBS have similar capabilities to predict sensory assessment of tenderness and subjective characteristics of beef, however there is limited information comparing these two instrumental methods under similar test conditions. Therefore, the present study was undertaken to correlate TPA parameters obtained using a star-shaped compression probe and WBS with trained-panel ratings of the sensory characteristics of cooked rib steaks.