The objectives of this research were to study the encapsulation of beta‐carotene (BC) in solid lipid microparticles (SLM) of palm stearin (PS) and stabilized with hydrolyzed soy protein isolate (HSPI), and also to investigate the effect of alpha‐tocopherol (TOC) addition to the systems. Through the characterizations of SLM produced with different formulations, it was verified that systems with 5% (w/v) PS, 1.0% (w/v) HSPI, and 0.3% (w/v) xanthan gum (XG) presented the highest stability, with average diameters of approximately 1.2 μm. This formulation was applied for the production of BC‐loaded SLM, with different concentrations of TOC. In SLM containing TOC, nearly 75% of encapsulated BC was preserved after 45 d of storage. The kinetic profiles for degradation of encapsulated BC were fitted to a pseudo‐1st‐order model, and the results showed that the main difference among the systems with different BC:TOC ratios was the residual concentration of BC. The stability of the BC‐loaded SLMs was also studied after stress conditions, and the results showed that the SLMs were able to support thermal treatments over 60 °C but presented low stability after different ionic strength stresses.
An approach to improve the stability and increase bioavailability of the beta‐carotene is to encapsulate this compound in lipid‐based matrices, such as the solid lipid microparticles (SLM). The production method (high shear mixing) applied in this study for the production of the beta‐carotene‐loaded SLM is easy to implement on an industrial scale. A great advantage of using SLM is that they do not require equipment such as high‐pressure homogenizers, thus making the SLM a cheaper ingredient for incorporation into food products than lipid nanoparticles.