Anais do Simpósio Latino Americano de Ciências de Alimentos
Proceedings of 14 SLACA - Latin American Symposium on Food Science

Anthocyanins have shown scientific and industrial interest not only for their potential as a natural food coloring, but also for their antioxidant potential. Thus, this research aimed to obtain extracts rich in anthocyanins from Isabel (Vitis labrusca) and Ruby grapes (Vitis vinifera), microencapsulate them and evaluate their stability at temperatures of 60, 75 and 90 °C for 2h and against artificial light with UVC lamp (λ = 254 nm) for 6h. The anthocyanins were extracted with ethanol:water (70:30) (v/v) by stirring for 40 min and the obtained extracts were evaluated for the content of total anthocyanins, by the differential pH method, and for the total phenolic compounds, using Folin-Ciocalteau reagent and gallic acid as standard. Subsequently, the extracts were microencapsulated with maltodextrin DE20 at a 1:10 ratio (extract:maltodextrin) (w/w) by lyophilization. As a result, the anthocyanin contents obtained were 37 ± 2 and 19.1 ± 0.6 mg of anthocyanins/100 g of grapes and the contents of phenolic compounds, expressed in gallic acid equivalents, were 74 ± 4 and 55 ± 1 mg EAG/100 g of grapes, for Isabel and Rubi grapes, respectively. The microencapsulation efficiency obtained was 94.7% and 63.1% for Isabel and Rubi grapes, respectively. Additionally, microencapsulation increased the stability of the extracts against the environmental factors evaluated, highlighting heating at 90 °C for 2 h, in which the microencapsulated Isabel grape extract revealed 82.5% retention of anthocyanins against 72.8% of the pure extract at 100 min, and for exposure to UV light, in which the microencapsulated Rubi grape extract showed 87% retention of anthocyanins against 63% of the pure extract after 6 h of exposure. The development of this project provided the obtainment of a natural additive for application as a colorant in foods with superior stability, with the differential of the antioxidant potential of this pigment.