METABOLOMIC AND MICROBIAL PROFILING OF TROPICAL/SUBTROPICAL FRUITS AND SMALL FRUITS FOR QUALITY FACTORS AND MICROBIAL STABILITY
Location: Citrus and Other Subtropical Products Research
Title: Evaluation of volatiles from two subtropical strawberry cultivars using GC-olfactometry, GC-MS odor activity values, and sensory analysis
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 26, 2011
Publication Date: December 14, 2011
Citation: Du, X., Plotto, A., Baldwin, E.A., Rouseff, R. 2011. Evaluation of volatiles from two subtropical strawberry cultivars using GC-olfactometry, GC-MS odor activity values, and sensory analysis. Journal of Agricultural and Food Chemistry. 59:12569-12577.
Interpretive Summary: Strawberry fruit are popular and a healthy option for consumers. Strawberry flavor is also widely used in the food industry. Flavor is comprised of sugars, acids and aroma compounds, the most complicated of which are the aroma compounds. This study looks at the volatiles in two Florida strawberry cultivars and determines which ones have odor activity and thus are likely contributors to strawberry aroma. This was also related to taste tests, to determine what aroma compounds contribute to particular sensory descriptors. This knowledge will help breeders develop better strawberries and food companies to improve strawberry flavor formulations.
Flavor profiles of two Florida strawberry cultivars were determined using GC-olfactometry,GC-MS, odor activity values (OAVs) and sensory analysis. Thirty-six aroma active compounds were detected using GC-O. Thirty-four were identified. The major odor-active compounds in decreasing intensity were: mesifurane, Furaneol, methyl butanoate, gamma-decalactone, unknown (grassy, LRI 1362), (E)-2-hexenal, linalool, (E, Z)-2, 6-nonadienal, geraniol, butanoic acid, methyl 2-methylbutanoate, and ethyl hexanoate. Over 90 volatiles were identified and 53 quantified using GC-MS including: 33 esters, 6 alcohols, 5 acids, 4 ketones, 3 aldehydes and 2 furanones. OAVs were determined for 46 volatiles of which 22 had OAV>1. Highest OAVs for 'Strawberry Festival' were: ethyl butanoate (461), Furaneol (424), methyl butanoate (358), and linalool (102). Nine of the volatiles with the 10 highest OAV values were also observed with high GC-O intensities. A 14-member trained panel evaluated quartered fruit using quantitative descriptive analysis to quantify seven flavor attributes. Sensory scores for "strawberry flavor" were correlated with "sweetness" (R2=0.83). Sensory "strawberry flavor" was also highly and significantly correlated to GC-MS methyl 3-methylbutanoate (R2=0.90), ethyl butanoate (R2=0.96) and methyl thioacetate (R2=0.92) concentrations.