An amount of 2 g of puree sample was homogenized with 10 mL of petroleum ether. Ultrasonication at a constant frequency of 40 kHz and 100 W for 30 min was used to assist the extraction. The ultrasonic bath (MRC Scientific Instruments, Netanya, Israel) is equipped with a digital control system of sonication time, temperature, and frequency. The resulting supernatant was collected and centrifuged at 9000× g at 10 • C for 10 min.
The absorbances for beta-carotene, lycopene, and total carotenoids were measured at 450, 470, and 503 nm, respectively. The contents of beta-carotene, lycopene, and total carotenoids were calculated as described by [23] .
The absorbances for beta-carotene, lycopene, and total carotenoids were measured at 450, 470, and 503 nm, respectively. The contents of beta-carotene, lycopene, and total carotenoids were calculated as described by [23] .
