Nyssa ogeche (white Tupelo) trees are concentrated mainly in the Appalachicola region in the panhandle of Florida.The honey produced from the nectar of these trees is regarded as a premium honey because its non-granulating tendencies and limited supply due to the small growing region and short bloom time of the Tupelo trees.Unfortunately there are few studies of this unique honey, with only one study done on the physicochemical characteristics and one on the volatiles present.Therefore, it is necessary to conduct an exhaustive physicochemical and flavor characterization of Tupelo honey to confirm and expand upon the limited available research. Physicochemical characteristics were determined for ten Tupelo honey samples from five different locations collected during two consecutive seasons (2013 and 2014).These included moisture content, ⁰Brix, water activity (Aw), pH, titratable acidity, ash content, and fructose and glucose contents.On the basis of pollen analyses, nine samples could be considered as authentic Tupelo honeys, with one (designated honey 3 from the 2014 season) containing mainly holly pollen along with appreciable levels of tupelo pollen.This honey also had a noticeably higher pH value and differed significantly in ash content from the other Tupelo honey samples, suggesting ash content to be a good indicator of botanical origin.Sensory screening indicated this sample to be significantly different from the other samples as well.Honey 5 produced during both seasons was the most consistent sampling location with the highest amount of Tupelo pollen content present in each sample.Panelists could not distinguish a difference between the honey 5 samples from both seasons during sensory testing.The characteristic most widely known about Tupelo honey is its relatively high fructose content which was confirmed in this study.Composition data were comparable to literature values and within the limits set by Codex Alimentarius. To complete a full flavor characterization, aroma-active compounds in Tupelo honey were identified by gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry-olfactometry (GC-MS-O).Initial analyses were performed on the same ten samples as described above by static headspace solid phase microextraction (H-SPME).Of the 40 compounds detected, the most important compounds based on their perceived odor intensities determined by two assessors were phenylacetaldehye (rosy) and nonanal (citrus).Further analysis was carried out on honey 5 from the 2013 and 2014 seasons due to its consistently high Tupelo pollen content across seasons and the inability of sensory panelists to distinguish between the two samples.The most potent odorants were determined through aroma extract dilution analysis (AEDA) of solvent extracts and sample dilution analysis by H-SPME (SDA-H-SPME).The most potent odorants identified by both dilution analyses techniques were vanillin (vanilla), phenylacetaldehyde (rosy), nonanal (citrus), (E)-2-nonenal (dried hay), eugenol (cloves), guaiacol (smoky), 2-phenylethanol (rosy, wine), 2’-aminoacetophenone (grape, corn tortilla), (E)-β-damascenone (cooked apple), and an unidentified odorant (RIwax=1731) described as spicy and hay-like.(E)-β-Damascenone was determined to be the most potent odorant with extremely high flavor dilution (FD) factors of 59,049 (2013 season) and 19,683 (2014 season).Quantification of (E)-β-damascenone using stable isotope dilution analysis combined with H-SPME (SIDA-H-SPME) revealed that the compound had an extremely high concentration and odor-activity value (OAV) compared to other types of honeys and food products.(E)-β-Damascenone may be used as a marker compound to distinguish Tupelo honey from other unifloral honeys because of the uniquely high levels present in this honey.
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Physicochemical and flavor characterization of Tupelo honey