Assessing gelling properties of chia (Salvia hispanica L.) flour through rheological characterization

BACKGROUND: Chia (Salvia hispanica L.) seeds are considered a promising ingredient for the development of functional products owing to their high nutritional value: 343 g kg⁻¹ lipids, 251 g kg⁻¹ protein and 226 g kg⁻¹ fibre. Considering chia's technological capacities, mainly the ability to swell when absorbing water and gel-forming properties, its addition to a food matrix can affect texture and rheological behaviour, acting as a texturing and stabilizing agent. The aim of the present work was to assess the gelling properties of chia flour through the rheological characterization of 100, 130 and 150 g kg⁻¹ chia flour gels. RESULTS: According to the mechanical spectra, all gels presented weak gel-like structures, as G′ was always less than a decade higher than G″, but higher chia flour concentrations showed a considerable increase in viscoelastic moduli. The gels had relatively low maturation times, almost instantaneous for lower concentrations, but the cooling rate affected the dynamics of formation of the gel structure. CONCLUSION: Based on texture and rheological properties, gels with 130 g kg⁻¹ of chia flour processed at 90 °C for 30 min showed the most suitable characteristics for use in the development of new food applications.