Nanocapsules of β-carotene: Thermal degradation kinetics in a scraped surface heat exchanger (SSHE)

Abstract

Response surface methodology was used to optimize the conditions of thermal degradation of β-carotene nanocapsules in a scraped surface heat exchanger. The variables studied were volumetric flow (2.4 × 10−6–4.8 × 10−6 m3/s), steam pressure (49–147 kPa), and rotor speed (10.4–31.2 s−1). Results showed that the experimental data could be adequately fitted into a second-order polynomial model with multiple regression coefficients (R2) of 0.842–0.977, and that the variables with the greatest significance in the degradation of the β-carotene were steam pressure and volumetric flow (p < 0.05). The responses analyzed were loss of β-carotene and changes in the degradation rate (k) and activation energy (Ea). The highest process conditions obtained for thermal degradation prevention were 4.4 × 10−6 m3/s of volumetric flow, steam pressure at 98 kPa, and a rotor speed of 38.29 s−1, with optimum values of k = 0.049 min−1, Ea = 171.49 kJ/mol, and loss of nanoencapsulated β-carotene = 6.93%.