This study aimed to produce microcapsules using ‘jabuticaba’ byproduct through lyophilization, and evaluate the stability of the powder, intended for use in gelatin. Three formulations were prepared, including the pure lyophilized extract (E), capsule with maltodextrin (CapM), and capsule with maltodextrin and xanthan gum (CapMG). The storage stability was evaluated at 4 and 25 ºC, and in the presence and absence of light, regarding color parameters, phenolic compounds and monomeric anthocyanins. The microencapsulated powders were applied in gelatin and analyzed for sensorial acceptance. Following an investigation of the storage stability of the three powders at 4 °C for 60 days, the sample that presented the best result was then analyzed at 25 ºC in the presence/absence of light. Microcapsules, independent of the encapsulant agent, exhibited lower values of degradation (2.82% phenolic compounds and 14.5% monomeric anthocyanins) than extract E when exposed to light and at 25 °C. Regarding color stability, CapMG showed smaller variations in the total color difference (ΔE) than the other samples. The lowest ΔE value corresponded to the gelatin sample with CapM, stored in the absence of light. It is possible to conclude that microencapsulation is an alternative for the preservation of ‘jabuticaba’ byproduct extracts, facilitating their use, retaining some compounds and protecting them against adverse conditions.
The influence of drying methods (oven drying at 50 °C, and freeze drying) on the centesimal composition, functional characteristics and rheological properties of mucilage obtained from chia seed and psyllium husk were investigated. Results showed that high temperature of oven drying reduced fiber content, solubility, emulsion activity and emulsion stability of mucilage. All samples showed pseudo plastic behavior, with the best result produced by Heschel-Bulkley and Power Law models of chia and psyllium mucilage, respectively. These results will be helpful in selecting suitable drying methods depending on the functional and rheological properties desired of the chia and psyllium mucilage in a food product.
This study focused on evaluating a technique for the psyllium husk mucilage (PHM) purification with simultaneous microencapsulation of curcumin. PHM was extracted with water and purified with ethanol. For the mucilage purification and simultaneous microencapsulation, an ethanolic solution of curcumin was used. After dehydration, the samples were analysed by instrumental techniques and evaluated for thermal stability. The presence of curcumin in the solution did not impair the yield of precipitated polysaccharide. Interactions of the dye and carbohydrates were confirmed by displacement of peaks in FT-IR and FT-Raman spectroscopy. The onset temperature of degradation of microcapsules was superior to that of curcumin. Thermal stability in solution at 90°C also improved. After 300 minutes of heating, the microcapsules had a remnant curcumin content exceeding 70%, while, in standard sample, the remaining curcumin content was 4.46%. Thus, the developed technique was successful on purification of PHM and microencapsulation of curcumin.
Muntingia calabura fruits are rich in bioactive compounds such as antioxidants, and the consumption of these compounds is associated with cancer prevention and aging. In this study, mathematical models were used to fit the experimental data of the Muntingia calabura peel drying kinetics, and the effective diffusion coefficient, activation energy and thermodynamic properties of the process were determined. Then, the effect of the drying temperature on the antioxidant activity and phenolic compounds of fruit peels was examined using conventional extraction and ultrasonication. Among the analyzed models, the logarithmic model was selected to represent the drying phenomenon of the calabura peel kinetics. The effective diffusion coefficient decreased by 74% as the temperature increased from 40 to 60°C, and the activation energy for liquid diffusion during drying was 23.96 kJ mol-1. The enthalpy and entropy decreased with increasing temperature, while the Gibbs free energy increased by 5% for each 10°C increase in temperature. Regarding the content of phenolic compounds and the antioxidant activity of the calabura peel, it was observed that an increase in the drying temperature had a positive effect on the conservation of the bioactive compounds, making it possible to conclude that drying at 60°C and ultrasound extraction are the most suitable approach to conduct the process.