RELATIONSHIP BETWEEN SENSORY AND INSTRUMENTAL ANALYSIS FOR TOMATO FLAVOR

The major components of flavor in tomato (Lycopersicon esculentum Mill .) and other fruit are thought to be sugars, acids, and flavor volatil es. Tomato overall acceptability, tomato-like flavor, sweetness, and s ourness for six to nine tomato cultivars were analyzed by experienced panels using a nine-point scale and by trained descriptive analysis pa nels using a 15-cm line scale for sweetness, sourness, three to five a roma and three to seven taste descriptors in three seasons. Relationsh ips between sensory data and instrumental analyses, including flavor v olatiles, soluble solids (SS), individual sugars converted to sucrose equivalents (SE), titratable acidity (TA), pH, SS/TA, and SE/TA, were established using correlation and multiple linear regression. For inst rumental data, SS/TA, SE/TA, TA, and cis-3-hexenol correlated with ove rall acceptability (P = 0.05); SE, SE/TA (P less than or equal to 10.0 3), geranylacetone, 2+3-methSlbutanol and 6-methyl-5-hepten-2-one (P = 0.11) with tomato-like flavor; SE, pH, cis-3-hexenal, trans-2-hexenal , hexanal, cis-2-hexanol, geranylacetone, 2+3-methylbutanol, trans-2 h eptenal, 6-methyl-5-hepten-2-one, and 1-nitro-2-phenylethane (P less t han or equal to 0.11) with sweetness; and SS, pH, acetaldehyde, aceton e, 2-isobutylthiazole, geranlyacetone, beta-ionone, ethanol, hexanal a nd cis-3-hexenal with sourness (P less than or equal to 10.15) for exp erienced or trained panel data. Measurements for SS/TA correlated with overall taste (P = 0.09) and SS with astringency, bitter aftertaste, and saltiness (P less than or equal to 10.07) for trained panel data. In addition to the above mentioned flavor volatiles, methanol and l-pe nten-3-one significantly affected sensory responses (P = 0.13) for cer tain aroma descriptors. Levels of aroma compounds affected perception of sweetness and sourness and measurements of SS shelved a closer rela tionship to sourness, astringency, and bitterness than to sweetness.