Joyce Maria Gomes da Costa

Microencapsulation of Rosemary Essential Oil: Characterization of Particles

This study evaluated the influence of wall material concentration (10–30%), inlet temperature (135–195°C), and feed rate (0.5–1.0 L · h−1) on the properties of rosemary oil microencapsulated by spray-drying, with gum arabic as carrier. Powder recovery, surface oil, oil retention, and hygroscopicity varied from 17.25%–33.96%, 0.03%–0.15%, 7.15%–47.57%, and 15.87%–18.90%, respectively. The optimized conditions were determined to be a wall material concentration of 19.3%, an inlet air temperature of 171°C, and a feed flow rate of 0.92 L · h−1. At this condition, particles presented no fissures and the compositions of pure and microencapsulated oil were similar. The sorption isotherms could be described by the GAB model.

Matrix structure selection in the microparticles of essential oil oregano produced by spray dryer

Abstract The goal of this work was to select the best combination of encapsulants for the microencapsulation of oregano essential oil by spray dryer with the addition of Arabic gum (AG), modified starch (MS) and maltodextrin (MA). The simplex-centroid method was used to obtain an optimal objective function with three variables. Analytical methods for carvacrol quantification, water activity, moisture content, wettability, solubility, encapsulation efficiency (ME) and oil retention (RT) were used to evaluate the best combination of encapsulants. The use of AG as a single wall material increased ME up to 93%. Carvacrol is the major phenolic compound existent in the oregano essential oil. Carvacrol exhibits a maximum concentration of 57.8% in the microparticle with the use of 62.5% AG and 37.5% MA. A greater RT (77.39%) was obtained when 74.5% AG; MS 12.7% and 12.7% MA were applied, and ME (93%) was improved with 100% of gum.

Physical and Thermal Stability of Spray-Dried Swiss Cheese Bioaroma Powder

The effect of water content on the glass transition temperature of Swiss cheese bioaroma microencapsulated with a spray dryer was determined using differential scanning calorimetry (DSC) while mass loss was determined by thermogravimetric analysis (TGA). The sorption isotherm behavior was assessed at 15–45°C. Data were fitted with different sorption models. The bioaroma microparticles were produced via spray drying in a matrix with a 1:1 ratio (w/w) of maltodextrin 20DE and modified corn starch (Capsul). The isotherms displayed Type II behavior, and the best fit was obtained by the Guggenheim–Anderson–de Boer (GAB) model (coefficient of determination R² ≥ 0.98). The DSC analysis showed that the increased equilibrium moisture content caused a significant reduction in the Tg of the microparticles. The samples stored at intermediate humidity showed thermal stability and the samples with equilibrium moisture content of 17.92% showed a lower mass loss.

POTENCIAL DE APLICAÇÃO DE MICROCÁPSULAS DE ÓLEO ESSENCIAL DE ORÉGANO EM QUEIJO QUARK

The objective was to evaluate the chemical composition and potential application of microcapsules of essential oil (EO) of oregano at different concentrations (0%, 0,25%, 0,50%, 0,75% and 1,0%) in cheese quark, in chemical composition and sensory acceptance and suitability of cheese Instruction no 53 and Ordinance no 146, to evaluate the potential application of these microcapsules inquark cheese. The five formulations differed significantly from each other in relation to moisture content and total solids, and as regression analysis, increasing the microcapsules concentration in the quark cheese will have the reduction of moisture and consequently increases the total solids content. In sensory evaluation of cheese quark formulations with up to 0,45% oregano essencial oil microcapsules showed a slight reduction in the acceptance and purchase intent by classifying between «like slightly / moderately liked» and «maybe buy / maybe not buy and probably buy it». Thus, the cheese produced is it according to the Instruction n. 53 and Ordinance n. 146 and the microcapsules show good potential for application in quark cheese.