Green ultrasound-assisted extraction of carotenoids from hot pepper pomace based on the bio-refinery concept and encapsulation

In this thesis study, it was aimed to provide carotenoid extraction and encapsulation according to the design of green extraction from pepper paste which is rich in phenolic content and antioxidant activity. The optimum solids:solvent ratio was determined to be 0.4 g/mL in order to achieve high yield extraction with a minimum amount of solvent in the direction of green extraction principles. In order to investigate the effects of extraction parameters on the extraction process, ultrasound assisted extraction was performed in refined olive oil with different power levels (80, 120 and 160 W) were measured with temperatures (30, 40, 50, 60ºC) and times (5, 10, 15, 20 min) β-carotene, capsaicin, total phenolic substances and antioxidant activity contents of the obtained extracts were determined and the highest carotenoid contents were encapsulated by freeze drying method using maltodextrin and gum arabic coating materials. The results showed that the maximum amount of β-carotene was provided by ultrasound-assisted extractions of 10, 15 or 20 minutes at a temperature of 40°C with ultrasonic power of 120 W. In addition, all extracts in the 120 W ultrasound power yield higher β-carotene and total phenolic material yields than other powers. At this power level, toal phenolic materials were adversely affected by high temperature and 15 and 20 min extractions, and the ideal extraction x parameter was determined to be 10 min at 40°C. Extracts were provided with high capsaicin content of extracts with extractions performed at 80 and 120 W ultrasound power and the maximum value of which is reached by ultrasound based extraction in 120 W ultrasonic power for 15 minutes at 50ºC. In addition, the validity of this study with the green extraction principles was confirmed by comparison with the results of 8 hour maceration extraction. Extracts obtained with ideal parametres for ultrasound-assisted extraction were encapsulated using a 1:4 coating material and a lyophilizer at -50ºC. The capsules showed 74.39±5.68% total carotenoid, 75.81±2.54% total phenolic content and 40.94±7.78 total antioxidant activity encapsulation efficiency. The morphology and size distribution of the microcapsules examined by scanning electron microscopy showed a heterogeneous appearance despite the spherical structures without fracture and the dimensions were found to be 6.70-23.03 μm.