OXIDATIVE STABILITY OF CHIA OIL ENCAPSULATED BY PICKERING EMULSIONS USING PROTEIN/DEXTRAN NANOPARTICLES

SPOTTI, MARÍA LAURA; ACOSTA, CAROLINA A.; QUINTERO CERÓN, JUAN PABLO; FIORAMONTI, SILVANA A.; SPOTTI, MARÍA JULIA; CARRARA, CARLOS R.

Raileigh, North Carolina

Conferencia; 15th Conference of Food Engineering (COFE); 2022

Society of Food Engineering

Chia oil (CO) is an excellent source of omega-3, but it is extremely prone to oxidation, which limits its incorporation into foods. Encapsulation by emulsification and their posterior drying could be an alternative to protect this type of oil and to obtain an ingredient that can be easily manipulated without detrimental effects on the organoleptic and chemical properties. Pickering emulsions are those emulsions stabilized by solid particles, which are adsorbed at the oil-water interface forming a coating that can enhance emulsion stability. The objective of this study was to evaluate the oxidative stability of CO in pickering emulsions obtained with nanoparticles (NP) of dextran /DX) and whey protein isolate (WPI) conjugates as emulsifiers, before and after spray drying at several storage conditions. WPI and DX of two molecular weights (MW: 6 and 100 kDa) were conjugated by Maillard reaction (WPI/DX6 and WPI/DX 100). The NP were obtained by two different methods: 1) random aggregation by heating (NP1), and 2) water in oil emulsification followed by heating (NP2). Then, the emulsions were dried in a spray dryer, and the powders were stored for 6 weeks at 4 and 30° C. The oxidative stability was measured by peroxide value (PV) and thiobarbituric acid reactive substances (TBARS). NP2 produced more polydisperse emulsions than NP1, which also showed less creaming stability. After 3 weeks at 30° C and 6 weeks at 4° C, all dried powders presented lower PV values than the maximum allowed by the Argentinian food code for cold pressed oils (