Influence of wall material selection on the microencapsulation of olive oil-extracted carotenoids from tomato peel

Abstract The biological activity of carotenoids is usually reduced due to isomerisation and oxidation of double conjugated bonds, which are very susceptible to light, high temperatures, acids, oxygen, metals, and free radicals. Microencapsulation can serve as a preventative measure against these reactions. The objective of the present study was the microencapsulation of a tomato peel extract to obtain a stable source of carotenoids, by evaluating the influence of different wall materials (polysaccharides, and animal and plant proteins) on the quality characteristics of both emulsions and microcapsules. Tomato peel extract was obtained using olive oil at room temperature, then emulsified and microencapsulated by spray-drying using maltodextrin, maltodextrin-chitosan, soy protein, pea protein, sodium caseinate and sodium caseinate-transglutaminase as wall materials. Most quality parameters of emulsions and microcapsules were significantly influenced by using different wall materials, however, none of the wall materials showed desirable values for all characteristics. Multivariate analysis indicated that maltodextrin, especially in combination with chitosan, was the most suitable wall material to increase the antioxidant capacity (0.40 µmol trol/g sample) and carotenoid retention efficiency process (61.83%), with SC as a close second, owing to its values for carotenoid content (14.02 µg ly/g sample) and yield (68.87%). The findings of this study provide a valuable foundation for the selection of wall materials to enhance the stability and functionality of carotenoid-rich ingredients.