Variation of lycopene and beta-carotene contents after harvesting of gac fruit and its prediction

The effects were investigated of three different stages of harvesting, the storage time and sample preparation methods before extraction using a Waring blender (WBM) or ball mill (BMM) on the lycopene and β-carotene contents from the gac aril. It was found that after harvesting and being stored at 26 ± 1 °C and 24±1% RH for 15 d, the lycopene contents from the color break, medium ripe and fully ripe stages of gac fruits grown in Thailand were in the ranges 0.11–8.99 mg/100 g fresh weight (FW), 3.88–22.94 mg/100 g FW and 18.95–50.11 mg/100 g FW, respectively, while the β-carotene contents were in the ranges 0.002–4.82 mg/100 g FW, 0.31–13.59 mg/100 g FW and 22.68–39.16 mg/100 g FW, respectively. In addition, neither the WBM nor the BMM sample preparation method had any significant (p > 0.05) effect on the analysis of these phytonutrients. Gac fruit at the fully ripe stage after 6 d of storage provided the highest lycopene content of 50.11 ± 1.59 mg/100 g FW, while the β-carotene was found highest (39.16 ± 1.29 mg/100 g FW) from fully ripe stage fruit after 15 d storage or when they had spoiled. Without classifying the fruits according to harvesting stages, equations for mixed ripe fruit were able to predict the lycopene and β-carotene contents in the aril with coefficients of determination of 0.77 and 0.89 with standard errors of the estimate of 16.09 and 6.39, respectively