Volatile Compound Profiles of Raw and Roasted Peanut Seeds of the Runner, Spanish and Valencia Market Types

Consumers are driven by roasted peanut flavor to purchase peanuts and peanut products. Different market types are used to create peanut products partially based on their roasted flavor characteristics. There is little information available in this area on the Spanish and Valencia market types. This study investigated the chemistry involved in roasted peanut flavor formation by examining the differences in the volatile organic compounds present in raw and dry roasted Spanish and Valencia market type peanuts when compared to those found in the more popular Runner types. The volatile organic compound (VOC) profiles were generated with headspace solid phase microextraction paired with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry. Mixed model ANOVAs and Tukey’s tests were employed for significance testing and to separate sample means. Principal component analysis and hierarchical cluster analysis were used to visualize the effects of roasting and market type on VOC profiles to ascertain the compounds responsible for the profile differences. The cluster analysis revealed some distinct patterns that distinguish market types and roast treatments. The raw peanuts were characterized primarily by alcohols, ketones, and aldehydes, and roasted profiles contained Maillard browning products such as pyrazines, pyrroles, and furans. Approximately 38% of the compounds found varied in abundance among the market types. Descriptive sensory analysis by a trained panel found the variation in the intensities of many attributes was greater between individual samples than between market types. This research establishes baseline VOC profiles of Spanish and Valencia market types that could help identify compounds that may contribute to roasted peanut flavor to optimize/preserve peanut flavor through peanut breeding and processing techniques.