Change of lycopene and soluble solids content of watermelon (kinnaree variety) at different maturity

Abstract

The change of lycopene and soluble solids content in watermelon (Kinnaree variety) at different maturity included commercial harvesting date was studied. The 90 fruits (15 fruits per one harvesting date) were harvested at 6 dates which were 19, 21, 23, 25 (commercial harvesting date), 27 and 29 days after flower blooming. The flesh in the middle part of 6.5×5×2 cm of half cut fruit was cut for measuring soluble solids content (%Brix) by refractometer and lycopene (ppm) by hexane extract using spectrophotometer. The soluble solids content was increased from 11.3 %Brix in the first harvesting date to 13.1 % Brix in the fifth harvesting date and decreased in the last harvesting date. The lycopene increased from 0.383 to 0.936 ppm. This data suggested that the farmers should not harvest watermelon after 27 days after flower blooming for the limit of its sweetness but if the lycopene content is a requirement the fruit should be harvested at 29 days after flower blooming. The information from this study will be useful to customers, farmers and the watermelon processing factory.