Effect of microwave followed by cooling on structural and digestive properties of pinhão starch

Effects of different oil additives on water resistance of corn starch straws

To investigate the effect of oil additives on improving the water resistance of corn starch straws, corn oil (CO), soybean oil (SO), rapeseed oil (RO), peanut oil (PO), lard (LD) and coconut oil (CCO) were chosen and compared the structure and properties of starch straws with different oil additives. Corn starch straws (CS), and starch straws supplemented with CO, SO, RO, PO, LD and CCO were prepared by thermoplastic extrusion. The results showed that the incorporation of oils effectively enhanced the water resistance of starch straws such as water absorption, water solubility and water swelling performance. Meanwhile, the flexural strength of starch straws significantly increased. There was no significant linear relationship among starch chain length, oil unsaturation and straw performance. Among seven starch straws, S-SO had the strongest hydrogen bond interaction (3289 cm-1) and relaxation time (0.96 ms). The S-CO had the highest relative crystallinity (16.82 %) and degree of double helix (1.535), hence resulting in the lowest water absorption and solubility values, the highest flexural strength (23.43 MPa), the highest ΔT value (9.93 °C) and ΔH value (4.79 J/g). S-RO had the highest thermal transition temperatures.

Effect of incorporating modified pinhão starch in alginate-based hydrogel beads for encapsulation of bioactive compounds by hydrodynamic electrospray ionization jetting

Known for its antioxidant properties, Araucaria angustifolia bracts extract was encapsulated using hydrodynamic electrospray ionization jetting within calcium alginate cross-linked hydrogel beads with varying contents of modified pinhão starch. The rheological properties of the dispersions and analysis of the physicochemical and digestive properties of encapsulated beads were studied. The results demonstrated that dispersions containing starch exhibited higher viscosity and reduced compliance values, indicating samples with stronger, more compact, and stable structures that are less susceptible to deformation. This was confirmed by the beads rupture strength test. The ATR-FTIR analysis suggest that no new chemical bonds were formed, with encapsulation being responsible only for physical interactions between the functional groups of the polymers used and the active groups of the compounds present in the extract. The thermal stability of starch-containing beads was higher. Total tannins were higher in beads containing starch, with 53.61 %, 56.83 %, and 66.99 % encapsulation yield for samples with 2 %, 4 %, and 6 % starch, respectively, and the remaining antioxidant activity ranged from 96.04 % to 81.08 %. In vitro gastrointestinal digestion simulation indicated that the highest releases occurred in the intestinal phase, ranging from 60.72 % to 63.50 % for the release of total phenolic compounds.