NON-DESTRUCTIVE QUANTIFICATION OF CAROTENOIDS IN INTACT WATERMELON (Citrullus lanatus) USING ON-LINE NEAR INFRARED SPECTROSCOPY

Fruit consumption is no longer merely a result of taste and personal preference, but is being a concern of health due to the fruit nutrients content1. Fruits and fruit-based products are increasingly becoming a significant component of the human diet worldwide and are associated with reduced risks of some types of cancer and cardiovascular diseases2. These beneficial properties appears to be related to antioxidants, mainly carotenoids. Even though human body does not synthetize carotenoids, they are ubiquitous and contribute to a number of biochemical processes balancing the oxidative stress of cells3. Chemically, they are a group of pigments, varying from yellow to red in colour, characterized by a C40 carbon chain highly unsaturated4. Lycopene exhibit the highest antioxidant activity and singlet oxygen quenching ability of all dietary carotenoids5. Alongside of tomatoes, which has been extensively studied as source of lycopene6,7, watermelon has moved up to the front of the line in recent research studies because the mean lycopene concentration of watermelon (37-122 mg/kg, depending on ripening stage and temperature during crop growth) is about 40% higher than the year-round mean for raw tomato (25-90 mg/kg). Moreover, in watermelon, lycopene is the most abundant (84-97%) carotenoid8.