Avocado Oil Encapsulation with OSA-esterified Taro Starch As Wall Material: Physicochemical and Morphology Characteristics

The objective of the work was to evaluate OSA-esterified taro starch as wall material to encapsulate avocado oil as lipophilic bioactive compounds, using spray drying for encapsulation. It was found that OSA-esterification decreased the amylose content (8.93-6.13%), %C (33.29-31.88%), and thermal properties of gelatinization (Tp: 86.1 to 80.7 degrees C, and Delta H: 8.4 to 7.9 J g(-1)). Besides, OSA-esterification did not modify the diffraction pattern (Type A). The OSA-starch granules did not show surface alterations, while showing a monomodal particle diameter distribution. However, the particle diameter increased from 2.8 to 3.3 um after modification. The emulsions of OSA-starch (350 and 400 mg starch. mL(-1) oil) showed greater stability against coalescence than those obtained with unmodified starch. Encapsulates with native and OSA-starches showed differences in diameter, shape and presence of pores. Likewise, the esterification reduces the diameter distribution in the microcapsules (15.1-13.1 mu m). The vegetable oil was located internally and superficially in the cavities and intraparticle area of the microcapsules. Encapsulation efficiency was increased by modification with OSA from 23.63 to 40.0% and the value of peroxides decreased during storage. The results demonstrated that malanga OSA-starch can be considered as wall material for protection of hydrophobic substance.