Chia (Salvia hispanica L.) seed mucilage release characterisation. A microstructural and image analysis study

- Chia seed mucilage can emerge as a potential industrial additive.
- Chia mucilage release can be studied by applying drug release mathematical models.
- Microscopy and Image analysis can be used to model chia mucilage release process.

Chia seed mucilage could be used as industrial additive due to its outstanding physical properties. However, not many reports about this gel have been published, maybe due to it remains tightly bounded to the coat seed during processing. The aim of this work was to characterise the chia seed structure and the mucilage release by microscopy, spectroscopy and image analysis techniques. Results showed that the mucilage is excreted from the polygonal cells of the epidermis coat, being composed mainly by carbohydrates fibres (18-45 nm width). It was observed from the kinetic modelling that the mucilage release follows a non Fickian process (0.5 < n < 1.0), presenting the best fitting the Peppas and Sahlin equation (R2 = 0.9984 and EDM % = 0.8). Chia mucilage could be used for the controlled release of drugs, or, as a result of the size of its fibres, for the production of nanocomposites.