Abstract
Peanut processors have often inquired about the sensory quality difference between market grades. A literature search indicates that information on this subject is not directly available nor uniformly presented. Where statistical tests were applied, larger size grades of peanuts generally were measurably superior in flavor to those of the smallest size grade (Jumbo Runner or virginia extra large kernels and medium versus No. 1). However, in none of the cited studies did panelists make paired comparisons of different grades of peanuts to determine whether the difference in flavor was discernable. In this study, a triangle comparison testing was used to determine if trained panelists could discern a flavor difference between adjacent grades of runner peanuts and the sensory attributes that might contribute to discernment. Discernment was attained in four out of 10 combinations: Jumbo Runner versus medium kernels of Florida MDR 98 and all three comparisons of medium versus No. 1. When the flavor data were pooled across combinations, panelists were able to correctly discern the difference between Jumbo Runner and Medium kernels 49% of the time (P < 0.05) and between medium and No. 1 kernels 90% of the time (P < 0.01). The adjusted mean sensory scores were significantly different among the three grades for fruity and sweet attributes but not for roasted peanut or bitter due to the presence of interaction between kernel size and genotype. The flavor intensity range between medium and No. 1 kernels for fruity and sweet was greater than 0.5 units. This difference is probably the reason why panelists were able to correctly discern between them 90% of the time. The basis for this discernment between Jumbo Runner and medium kernels appeared to be differences in bitterness, but the direction of the difference was not consistent across genotypes.
Author notes
1The research reported in this publication was a cooperative effort of the Agricultural Research Service of the U.S. Dept. of Agric., the North Carolina Agric. Res. Serv., Raleigh, NC 27695-7643 and the Univ. of Florida Agric. Exp. Sta., Gainesville, FL 32611-2073. The use of trade names in this publication does not imply endorsement by the USDA, the NCARS, or the Univ. of Florida Agric. Exp. Sta. of the products named, nor criticism of similar ones not mentioned.