Encapsulation of carotenoids extracted from tomato waste

Abstract

Utilization of carotenoids as a nutraceutical ingredients or natural colorants within foods is currently limited due to their instability. Encapsulation is one of the prominent means used to improve carotenoid stability. In this study the content of bioactive compounds (lycopene, ?-carotene and phenolics) and antioxidant activity (DPPH, ABTS, superoxide anion and reducing power test) were investigated in the tomato waste extract. Based on the obtained results, tomato waste showed high contents of lycopene (13.72 mg/100 g DW), ?-carotene (12.36 mg/100 g DW) and phenolic compounds (203.33 mg/100 g DW). Also, high values of antioxidant activity were determined in all applied tests. To protect extracted sensitive carotenoid compounds (lycopene and ?-carotene) tomato waste extract was encapsulated with various encapsulating materials (soy protein, pea protein, inulin and gum arabica) by freeze drying method. The influence of applying different encapsulating materials on the encapsulation efficiency of carotenoids (lycopene and ?-carotene) was studied. Also, obtained encapsulates were characterized in terms of water activity, moisture content, hygroscopicity, flowability, density ratios and particles size. Encapsulate on the basis of gum arabic showed highest encapsulation efficiency of ?-carotene (53.47%), while encapsulate prepared with soy protein as encapsulating material showed highest encapsulation efficiency of lycopene (51.44%). The results of this study support the need for preparation of encapsulates with different encapsulating material and evaluation of their characteristics with the aim of development powder forms suitable for supplementation and food fortification.