Powdered o-limonene microcapsules obtained by spray drying using native and thermal-treated Brea gum as wall materials

Brea gum (BG) and thermal-treated BG (BGTT) were studied as wall materials in the encapsulation of o-limonene and compared to gum Arabic (GA). Infeed emulsions were prepared with 10% w/w of o-limonene and 90% w/w of gum solutions: solutions of BG at different concentrations and solutions of BGTT treated during different times. Powdered microcapsules were obtained by spray-drying the emulsions and characterized through scanning electron and confocal microscopies, color, water activity, moisture, and limonene stability determinations. Quantitative analysis of o-limonene after drying showed that a high amount of limonene was loosed. During storage, BGTT powders showed great improvement in limonene retention overcoming BG and GA, which was attributable to the large particles with a matrix-type inner structure in BGTT powders that protected limonene. These findings showed that new molecular species in BGTTs improved their encapsulation properties, thus BGTTs could be used as alternative matrixes in replacement of GA.