Lycopene is the predominant carotenoid pigment in tomatoes and primarily responsible for red color. Spectrophotometric procedures for lycopene evaluation although accurate are time consuming and destructive. The objective of this study was to relate chromaticity values (L*,a*,b*) measured using a Minolta Chroma Meter CR-200b portable tristimulus calorimeter with lycopene concentrations in the pericarp of 'Celebrity', 'Mountain Delight' and 'Early Pick' tomatoes. Fruit were selected to encompass varying maturities from green to red ripe and were obtained from a commercial source. Lycopene from individual skin disks or pericarp plugs corresponding to each location of color measurement was extracted in acetone and measured spectrophotometrically at 503 nm. The L* value (a measure of lightness) or a* value (a measure of redness) was determined to be well correlated with lycopene concentration in all 3 cultivars. The linear regression of the lycopene concentration on the ratio of (a*/b*) provided the best R for all cultivars (0.75).
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