Submitted to: Proceedings of Florida State Horticultural Society
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/10/2007
Publication Date: 3/20/2008
Citation: Kerbiriou, P., Plotto, A., Goodner, K., Baldwin, E., Gmitter, Jr., F.G. 2007. Distribution of aroma volatiles in a population of tangerine hybrids. Proceedings of Florida State Horticultural Society. 120:267-275. Interpretive Summary: Orange, mainly, and grapefruit dominate the fresh fruit market in Florida. Whereas grapefruits are very sensitive to canker, tangerines are not and therefore would constitute an interesting alternative to grapefruit on the fresh fruit market. Breeding programs in Florida focus on fruit quality, tangerine flavor and aroma would thus be interesting traits to be considered for breeding. Volatile compounds are well known to contribute to flavor and aroma, therefore this study was undertaken to identify the volatiles present in tangerine juice, to find relationships between hybrids regarding their volatile composition, and to investigate the influence of parentage and harvest date on volatile composition. In total, 45 hybrids were harvested over the season (from December 2006 to March 2007). Ethanol, a-pinene, cymene and d-limonene were the volatiles common to all the samples. The statistical analyses highlighted several samples apart from the other samples because of their particular richness in volatiles. The parents 'Fallglo' and 'Fairchild' were found to influence the volatile composition of their hybrids, as well as the parent 'Murcott'. Samples having sweet oranges in their genetic background were grouped together because they were rich in esters, which are volatiles known to impart a fruity note to orange juice. The results of this study will be used to understand a sensory analysis of the samples.
Technical Abstract: While orange juice volatile composition has been well studied, little is known about volatiles in tangerines. This study was undertaken to determine the most common compounds present in 45 tangerine hybrids, and to find relationships among these hybrids based on volatile content. Fruits were harvested from November 2006 to March 2007. A juice composite sample of approximately 20 fruits was analyzed by gas chromatography mass-spectrometry. Among the more than 200 identified volatiles in total, ethanol, a-pinene, cymene and d-limonene were found in all the samples. These compounds were previously reported in citrus products (essence, peel oil, juice, etc). A principal component analysis showed that hybrids '9-1', '8-10', and 'Hongju' were different from the others because a larger than average number of volatile were detected in those samples. A cluster analysis based on presence/absence of volatiles revealed ten main clusters influenced by harvest date and/or progenitors, highlighting relationships among certain hybrids based their volatile composition. Cluster 2 mainly grouped samples having 'Fallglo' and 'Fairchild' in their parentage, while cluster 4 mainly grouped samples having a common parent 'Murcott'. Cluster 10 grouped samples having sweet oranges in their genetic background and being rich in esters, which are known to give a fruity note to orange juices. This method provided useful information on tangerine hybrid volatile content in relation to their genetic make-up.