Submitted to: Institute of Food Technology
Publication Type: Abstract Only
Publication Acceptance Date: 12/15/2004
Publication Date: 3/21/2005
Citation: Beaulieu, J.C., Lea, J.M. 2005. Volatile characterization in seedless watermelon cultivars using spme. Institute of Food Technology. 84-1.
Technical Abstract: Seedless triploid watermelons Citrullus lanatus (Thunb.) have increased in popularity since the early 1990's, and the demand for seedless fruit is on the rise. Sweetness and sugars are crucial breeding focus for fruit quality. Volatiles also play an important role, yet we found no literature for seedless cultivars, and no reports using SPME in watermelon. The objective of this experiment was to identify volatile and semi-volatile compounds in 5 seedless watermelon cultivars using Carboxen/DVB/PDMS SPME with GC-MS. Fully ripe, 2-day old fresh watermelons, were sanitized, rinsed, and the rind removed with a sharp knife. Thick slices (2 inches) were cut and placed on a Silver King Kutlett to cut 1 x 1 x 2'' bars. Three bars were combined and squeezed through miracloth to produce rapid juice extracts for immediate headspace SPME GC-MS. Aldehydes, alcohols, ketones, and 1 furan (2-pentyl furan, a lipid oxidation product) were recovered. Based on total ion count peak area, the most abundant compounds in 4 cultivars were 3-nonen-1-ol/(E,Z)-2,6-nonadienal (28.2 ' 29.5%), (E)-2-nonenal (14.9 ' 22.9%), and (Z)-6-nonenal/nonanal (8.7 ' 22.4%). Hexanal was most abundant (39.7%) in one cultivar. The most abundant ketone was 6-methyl-5-hepten-2-one. Some sensory attributes reported for these compounds are melon, citrus, cucumber, orange, rose, floral, guava, violet, vegetable, green, grassy, herbaceous, pungent, fatty, sweet, and waxy. Target ion monitoring and quantification will ultimately determine the relative contribution of the compounds. Once identified and related to sensory attribute, we can monitor the critical flavor compounds in seedless watermelon after processing and throughout storage.