Submitted to: Journal of Food Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/15/2023
Publication Date: 6/30/2023
Citation: Weissburg, J.R., Johanningsmeier, S.D., Dean, L.L. 2023. Volatile compound profiles of raw and roasted peanut seeds of the runner and virginia market-types. Journal of Food Research. 12(3):47-68. https://doi.org/10.5539/jfr.v12n3p47.
Interpretive Summary: Peanut products are prized by consumers for their unique roasted flavors. Maintaining and enhancing those flavors is one of the goals of USA peanut plant breeders. Knowledge of the compounds that create the flavors is limited. As a result, the information on compounds that need to be present in raw peanuts to form the flavors on roasting is lacking. Plant breeders need this information to produce better new cultivars for commercial peanut production. This study evaluated the compounds in runner and Virginia market-types peanuts which make up over 80% of the peanuts grown in the US. A large number of compounds were identified and tabulated using the most up to date chromatography instrumentation including some that have never been reported in peanuts before. This information is now available for advanced peanut plant breeding use.
Technical Abstract: The unique flavor of peanuts that develops during roasting is the primary driving force for the consumption of peanut products. Although rarely consumed raw, the raw state of the peanut contains the precursors involved in the transformations that lead to the distinct flavor development in roasted peanuts. Volatile compounds extracted from the headspace above raw and roasted peanut samples of the runner and virginia market types by solid phase microextraction were characterized using two-dimensional gas chromatography coupled with time-of-flight mass spectrometry. The roasting treatment and peanut market-type each had a significant impact on the types and concentrations of small molecular weight compounds found. Among 361 sample components detected, 290 compounds were found to be significantly different between the raw and roasted treatments (p < 0.05). The roasted samples contained pyrazines, pyrroles, thiazoles, and furans. Alcohols were the primary compounds found in the raw peanut samples. Additionally, 107 compounds were found to differ significantly between roasted runner and virginia-type peanuts. Virginia-type peanuts contained higher levels of linoleic acid oxidation products, such as 2-octenal, hexanal, and 1-octen-3-one. More significant distinctions in volatile compounds were recognized between runner and virginia market types than previously observed. In total, this study reported 119 volatile compounds that have not previously been reported in roasted peanuts, including 11 furans, seven pyrroles, five pyridines, and 12 pyrazines.