Evaluation of sensory methodology for ground beef : effect of variation of time, holding method and panels

This study was divided into two parts for evaluating sensory methodology for ground beef patties. In the first study a blend of grain-grass produced beef (50-50) (15% fat) was used to investigate and determine the optimal holding time and holding method for maintaining the temperature of ground beef patties prior to serving panelists. Also, the effects of time and holding method on the sensory quality of ground beef patties were determined for this study. A 9-member trained panel evaluated the patties for juiciness and flavor using a structured descriptive scale with 8 = extremely juicy, 1 = extremely dry for juiciness and 6 = no off-flavor, 1 = extremely intense off-flavor for flavor. The heating tray and water bath methods (50-55° C) had higher juiciness and flavor ratings than the room temperature method (22° C). A holding time of 0 minute was significantly different (P<0.05) from 30, 60, and 90 minutes for juiciness. For flavor, 0 and 30 min-utes differed from 90 minutes and 30 minutes differed from 60 minutes. There was a significant interaction between holding time and method. As time increased both juiciness and flavor scores for the room temp-erature method decreased. Flavor scores for the other two methods in-creased steadily, while the juiciness scores fluctuated over time. These scores were higher for 60 minutes and lower for 30 and 90 minutes. In the second study, the best holding method, which was the heating tray method, from the previous study was used for maintaining the temperature. The meat treatments used were grain-produced beef (21% fat), grass-produced beef (9%), and the grain-grass blend (15% fat) from study one. These meat treatments were used to investigate the variation and repeatability of trained and untrained panelists. Trained panelists from the first study and 33 untrained panelists evaluated the patties for juiciness and flavor using the scale from study one and an 8-point scale for overall acceptability. Trained and untrained sensory panelists differed significantly (P<0.05) in evaluating juiciness and flavor of ground beef patties. The trained panelists' scores were higher for juiciness and flavor then the untrained panelists. The grass-produced beef patties were rated lower for both juiciness and flavor than the other two meat treatments. Overall acceptability of the three meats did not differ significantly for trained and untrained panelists.