Óleo essencial de gengibre (Zingiber officinale L.) microencapsulado por spray drying em diferentes matrizes poliméricas

Abstract

Spray drying is an important method used by the food industry in the production of microencapsulated aromas, improving its handling properties, dispersion, release of active components and aiding in the development of new products. We evaluated the effect of the partial substitution of gum Arabic for maltodextrin and inulin, used as wall materials, over the emulsion properties and microencapsulated ginger essential oil by means of spray drying. In addition, we studied the partial substitution of the whey protein isolate for maltodextrin and inulin. The mixture of gum Arabic and maltodextrin, and whey protein isolate and maltodextrin, wall materials that presented good physical and chemical properties, among which high volatile retention, are alternatives for encapsulating ginger essential oil. Despite the addition of inulin having reduced oil retention, the treatments showed that this encapsulating agent is an interesting substitute for gum Arabic in food. This contributes for increasing the possibilities of new encapsulating formulations and places inulin, a fiber with proven functional activities, as an alternative for encapsulating agent in food production. The combined use of cashew gum and inulin can also be considered an alternative in the process of encapsulating essential oils and in the development of new products using non-conventional natural biopolymers. The essential oil microencapsulated in the matrix of the cashew gum and inulin in the proportion of 3:1, m/m, presented the best physical and chemical properties, especially concerning encapsulation efficiency. By means of optimizing the whey protein isolate and inulin matrix, and considering the variables wettability, encapsulation efficiency and dispersity, the results indicated that the concentration of wall material of 22 % and the inlet air temperature of 170 °C are the best conditions for the spray drying process of ginger essential oil.