Evaluation of Volatiles from Two Subtropical Strawberry Cultivars Using GC-Olfactometry, GC-MS Odor Activity Values, and Sensory Analysis

Most strawberry flavor studies have examined berries grown in temperate regions with long summer days. Few studies have examined berries harvested in winter months from subtropical regions with shorter photoperiods. Fruits harvested in February and March from two strawberry cultivars, 'Strawberry Festival' and 'Florida Radiance', were examined. Thirty odor active compounds were detected using time-intensity GC-O. Twenty-nine were identified. The major odor active volatiles in both cultivars were 2,5-dimethyl-4-methoxy-3(2H)-furanone (DMMF), 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF), methyl butanoate, gamma-decalactone, unknown (grassy, LRI 1362, wax), (E)-2-hexenal, linalool, (E,Z)-2,6-nonadienal, geraniol, butanoic acid, methyl 2-methylbutanoate, and ethyl hexanoate. Over 90 volatiles were identified and 54 quantified using GC-MS including 33 esters, 6 alcohols, 5 acids, 3 aldehydes, 3 lactones, 2 ketones, and 2 furanones. Odor activity values (OAVs) were determined for 46 volatiles, of which 22 had OAV > 1. The highest OAVs for 'Strawberry Festival' were ethyl butanoate (461), DMHF (424), methyl butanoate (358), and linalool (102). A 14-member trained panel evaluated quartered fruit using quantitative descriptive analysis to quantify seven sensory attributes. Sensory strawberry flavor scores were positively correlated with sensory sweetness (R-2 = 0.83) as well as GC-MS methyl 3-methylbutanoate (R-2 = 0.90) and ethyl butanoate (R-2 = 0.96). These cultivars lacked methyl anthranilate and possessed an aroma pattern different from summer-grown strawberries.