Evaluation of the addition of artichoke by-products to O/W emulsions for oil microencapsulation by spray drying

Abstract

[eng] This study aimed to evaluate the use of artichoke bracts in oil microencapsulation by spray drying. Thus, 1% and 2% w/w of this material was added to sunflower O/W emulsions to partially replace maltodextrin and substitute Tween®20. Emulsions were compared with a control containing only maltodextrin as wall material and Tween®20 as emulsifier. The emulsion containing 2% of artichoke exhibited higher (p < 0.05) viscosity and stability against coalescence and flocculation (24 h) and 20% higher encapsulation efficiency after spray drying, compared with control. The three microcapsules showed similar microstructure, density, porosity, flow properties, and Tg. Microcapsules containing artichoke exhibited, on average, 15% larger particles, 19% lower moisture content, and 9% lower solubility, besides perceptible colour changes. Microcapsules containing artichoke (2%) showed lower oxidation indicators content (37%) after spray drying and over 2 months of controlled storage (35 °C, 50% relative humidity) than control. After 90 days, decreases in linoleic acid were observed in all the samples (up to 24%), with increases of oleic and saturated fatty acids. The control showed the highest increase in saturated fatty acids (73%). Hence, artichoke bracts can be exploited for their application in lipid microencapsulation because of their emulsifier properties and the oxidative protection they provide.