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Red beets is rich in phenolic acids and has high antioxidant capacity, and can be used to produce a natural dye. This study evaluated the effect of pH (3 to 6) on the stability of red beet extract microcapsules, dried by freeze drying and spray drying and stored at room temperature. The microcapsules were produced using a combination of maltodextrin and xanthan gum as encapsulating agents and stored for 7 days. For all evaluated microcapsules, a degradation of betanin was observed, however, that degradation was independent of pH, with the exception of the sample with maltodextrin and dried by spray drying. The freeze dried products showed lower degradation constants and higher half-life (t 1/2) when comparing with the spray dried samples. The microcapsules containing maltodextrin and xanthan gum, dried by spray drying, showed the highest change in the content of phenolic compounds after storage for 7 days. The color parameters showed a reduction for a*, and increase in b* and L*, for all samples during the storage time. In general, the microcapsules produced using maltodextrin and xanthan gum, and dried by freeze dryer, showed higher stability in terms of betanin content, phenolic compounds and color parameters during storage at different pHs.

Titanium dioxide (TiO2) in different forms such as films, fibers or particles are being extensively studied for removal of contaminants from aquatic environments due to its outstanding photocatalytic activity. This work reports the development of TiO 2 -polyamide 12 electrospun fiber mats. A systematic study on the influence of electrospun processing parameters on polymer fiber morphology was performed. It was observed that the average fiber diameter is mainly influenced by polymer concentration and average fiber diameters between 404 ± 82 nm and 1442 ± 360 nm were obtained. Polyamide-12 (PA-12) was used as a polymer matrix and electrospun with 0, 10 and 20 wt% of TiO 2 . It was observed that the filler does not change the average fiber diameter, being similar to that observed for neat PA-12 fibers processed under the same experimental conditions. The TiO 2 were particles dispensed not only in the bulk of the polymeric matrix but also on the surface of the fibers, especially for the samples with higher filler contents. Neat and nanocomposite electrospun samples show a hydrophobic behavior and a degree of crystallinity of ~25%. The photocatalytic performance of the processed samples was measured by following the degradation capability of a chosen dye, methylene blue (MB). Results show that the nanocomposite samples have a remarkable photocatalytic activity, especially the one with a higher load of TiO 2 particles (20 wt%), with all MB being removed from the solution after 100 min. AbstractTitanium dioxide (TiO 2 ) in different forms such as films, fibers or particles are being extensively studied for removal of contaminants from aquatic environments due to its outstanding photocatalytic activity. This work reports the development of TiO 2 -polyamide 12 electrospun fiber mats. A systematic study on the influence of electrospun processing parameters on polymer fiber morphology was performed. It was observed that the average fiber diameter is mainly influenced by polymer concentration and average fiber diameters between 404±82 nm and 1442±360 nm were obtained.Polyamide-12 (PA-12) was used as a polymer matrix and electrospun with 0, 10 and 20 wt% of TiO 2 . It was observed that the filler does not change the average fiber diameter, being similar to that observed for neat PA-12 fibers processed under the same experimental conditions. The TiO 2 were particles dispensed not only in the bulk of the polymeric matrix but also on the surface of the fibers, especially for the samples with 2 higher filler contents. Neat and nanocomposite electrospun samples show a hydrophobic behavior and a degree of crystallinity of ~ 25%.The photocatalytic performance of the processed samples was measured by following the degradation capability of a chosen dye, methylene blue (MB). Results show that the nanocomposite samples have a remarkable photocatalytic activity, especially the one with a higher load of TiO 2 particles (20 wt%), with all MB being removed from the solution after 100 min.

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This study aimed to produce and characterise citrate esterified resistant starch (RS) from cassava, and apply it in a dairy beverage. The citrate esterified cassava starch (CECS) was prepared by thermo‐acid catalysed esterification and the product was characterised for RS content, solubility, swelling power, and water absorption. Scanning electron microscopy, viscoamylographic analysis, X‐ray diffraction and Fourier‐transform infrared spectroscopy were used. The CECS was added to a dairy beverage and then the rheological and sensory characteristics were evaluated. The results showed a 60.08% increase in RS content, revealing the occurrence of fissures and overlapping layers in the starch granules. There was a decrease in solubility, swelling power and water absorption, and formation of ester bonds. The rheological characteristics showed a non‐Newtonian pseudoplastic fluid behaviour for the CECS incorporated dairy beverage. The addition of 1.5% CECS to the dairy beverage influenced the colour, taste and consistency, while the addition of 0.5% CECS showed a greater purchase intention, providing an opportunity for development of functional dairy products. In conclusion, this work shows that the developed resistant starch is a promising functional ingredient, with promising applications in the food industry.