Effect of nanoencapsulation on the solubility and antioxidant activity of astaxanthin pigmented oil extracted from shrimp waste (Litopeneaus vannamei)

Astaxanthin-pigmented oil from shrimp waste meal was nanoencapsulated by O/W emulsification using porcine gelatin (EAG) and a combination with soy protein (EAGS 2:2 and EAGS 3:1) to improve the solubility and antioxidant activity of the pigmented oil. The encapsulates presented spherical shape and smooth surface; particle size equal to 159.68 (14.42) nm for EAG, 192.72 (10.44) nm for EAGS 2:2, and 95.41 (17.83) nm for EAGS 3:1; amorphous structure; and chemical interactions. The oil incorporation efficiency ranged from 87.60-89.20%, the percentage of astaxanthin incorporated was approximately 68%, and the dispersibility in water around 50%. The antioxidant potential evaluation indicated that all formulations preserve or enhance the antioxidant activity of the oil up to three times than non-encapsulated oil. Therefore, porcine gelatin alone or in combination with soy protein was effective in promoting the solubility and enhancing the antioxidant activity of the astaxanthin-pigmented oil, demonstrating interesting characteristics for use in food.