2023 Volume 24 Issue 4 Pages 103-111
The waste rate of watermelon juice by using the white part of the rind was in the range of 20 to 30% at all days after pollination (DAP), which was lower than the 40% listed in the Standard tables of food composition in Japan. The color of the juice fluctuated with a peak at 40 DAP, based on L＊ and a＊ values. The brix of the juice stabilized after 40 DAP, when the fruit was fully ripe, and was maintained at about 10 °Bx, suggesting that the juice could be used. Each 100 g of the juice contained 164.7 mg of citrulline (40 DAP), 41.9 mg of arginine (50 DAP), 16.5 mg of γ-aminobutyric acid (50 DAP), 3.34 mg of lycopene (40 DAP), and the singlet oxygen absorption capacity value was 8.62 μmol α- tocopherol equivalent/mL (40 DAP). The correlation between singlet oxygen absorption capacity values (y) and a＊/b＊ values (x) was strong (correlation coefficient = 0.915), and a regression equation (y = 5.824 x − 4.448) was obtained, suggesting the possibility that the a＊/b＊ values can predict singlet oxygen absorption capacity values.
