Submitted to: American Peanut Research and Education Society Abstracts
Publication Type: Other
Publication Acceptance Date: 7/9/2006
Publication Date: N/A
Citation: N/A Interpretive Summary:
Technical Abstract: Sensory quality of peanut (Arachis hypogaea L.) products is the main reason that consumers buy them. We previously documented a decline in the intensity of roasted peanut sensory attribute in Florunner and NC 7 peanuts over a 15-year period. Because the same two genotypes were evaluated throughout this period, the decline must have been due to changes in environmental factors across years. The objective of this study was to determine if any of a set of common cultural practices used in peanut production exerted an influence on flavor of roasted peanuts. SMK samples were obtained from studies of cultural practices conducted in 2003 and 2004 including combinations of in-furrow aldicarb with secondary growth regulator treatments, an array of leaf spot control programs, combinations of leaf spot programs with conventional or strip tillage, and combinations of rotational crops with irrigation. Samples were roasted to a color within a standard range, ground to paste, and evaluated by an eight-member trained descriptive sensory panel. Sensory attribute intensity scores were analyzed according to the statistical design of the individual field experiment. None of the treatments investigated had a significant main effect on roasted peanut intensity, but there were there were several treatments that affected bitterness or astringency. When aldicarb was placed in-furrow, the growth regulator/herbicide 2,4-DB reduced astringency. In trials of leaf spot control programs, application of azoxystrobin increased bitterness while application of tebuconazole or propiconazole/trifloxystrobin trended toward reduction of bitterness. Leaf spot control program had a differential effect on bitterness depending on the level of tillage, conventional or strip-till. An interaction was observed for roasted peanut intensity in comparing irrigated versus non-irrigated peanuts following corn versus following cotton or peanut. Compared with peanuts that followed a corn crop, bitterness was increased in peanuts following cotton or peanut. Overhead irrigation reduced bitterness while subterranean irrigation increased it. The mechanisms whereby these treatments influenced flavor have not been determined. None of the detected effects was larger than half a flavor intensity unit, i.e., considered to be at the threshold of perception by the consumer. None of the cultural practices evaluated to date had a sufficiently large effect to explain the substantial decline in roasted peanut attribute intensity observed earlier.