Relationship between sensory perceptions and volatile and phenolic compounds of fresh basil ( <i>Ocimum basilicum</i>  L.) evaluated by multivariate statistics

Sensory and phytochemical analyses were conducted on sweet basil (Ocimum basilicum L.) to investigate the impact of volatile and phenolic compounds on aroma, taste, and flavor by mouth. A trained panel evaluated seven accessions, including 'Aroma 2', 'Nufar', 'CB19', and four breeding lines developed by Rutgers for downy mildew resistance (DMR). The basils selected for this study displayed unique sensory profiles that were chemically characterized with 21 volatile and 15 phenolic compounds using GC/MS and LC/MS, respectively. Principal component analysis revealed a two-factor model. Factor 1 described cinnamon, floral, ginger, lemon, and musty aromas, clustering with eucalyptol and many minor aromatic compounds. 'Rutgers Thunderstruck-DMR' closely aligned with these attributes. Factor 2 described an axis with clove aroma/flavor and bitter taste on one end and anise and sweet aroma/taste on the opposite end. Anise aroma/flavor was closely associated with methyl chavicol and sweet aroma/flavor. Eugenol and several phenolic acids clustered near bitter taste. However, not all phenolic acids contributed to bitterness or astringency, suggesting diverse roles in sensory perception. 'Aroma 2', 'Rutgers Passion DMR', and 'Rutgers Obsession DMR' were aligned with the clove/spicy/bitter pole of Factor 2, whereas 'CB19' was oppositely aligned with the anise/sweet pole. 'Nufar' and 'Rutgers Devotion DMR' occupied the center of the plot and were characterized as moderate in their sensory/phytochemical profiles. In conclusion, this study reveals that new varieties can be distinguished by their sensory/phytochemical profiles and compared to commercial cultivars. Further, the inclusion of phenolic compounds led to more precise sensory/phytochemical descriptions of these varieties. PRACTICAL APPLICATION: This research provides valuable insights into the aroma, flavor, and underlying phytochemistry of fresh basil, which can help improve its taste and quality for culinary use. Sensory scientists and breeders can use the tools presented in this study as a means of selecting basil varieties to identify 'off types' and enhance aroma and flavor profiles.