Microwave-assisted extraction of carotenoids from carrot juice processing waste using flaxseed oil as a solvent

The present study was aimed to evaluate the effect of microwave technology on the extraction yield of carotenoid from carrot juice processing waste using flaxseed oil as solvent. Response surface methodology was employed to optimize the effect of microwave power, extraction time and oil to waste ratio on percentage recovery of carotenoid. Optimum conditions obtained for microwave-assisted carotenoid extraction were 165 W of microwave power, 9.39 min of extraction time and 8.06:1 g/g of oil to waste ratio which gave carotenoid recovery of 77.48%. Selected physical and chemical properties of flaxseed oil and carotenoid enriched flaxseed oil were investigated in terms of fatty acid composition, acid value, peroxide value, p-anisidine value, colour parameters (L*, a* and b* values), beta-carotene content, total phenolic content and antioxidant activity. The results showed that the enriched flaxseed oil was in good quality and had high phenolic content (214.05 +/- 1.61 mu g GAE/g oil) and antioxidant activity (inhibition % of DPPH = 70.67 +/- 0.85).