Rheological Properties of a Fibro-Protein Extract from Male date Palm Flowers

Fibro-protein extract from male date palm flowers (FPE-MDPF) was obtained by alkali extraction followed by isoelectric precipitation. The FPE-MDPF consisted mostly of carbohydrates (64.67%) andproteins (26.82%). The extract dispersions showed shear-thinning behaviour which was pronounced with the concentration increase. The Herschel Bulkley model was used for the viscosity curves evaluation and the obtained parameters indicated a remarkable deviation from the Newtonian regime. Both viscosity and viscoelastic moduli were influenced by the modification of extrinsic conditions. In fact, it was revealed that the concentration increase (2 up to 6 %), the acidic condition (pH 4) as well as the salt addition (0.5 M) contribute to the increase of viscosity and the strengthening of the obtained gels. Moreover, after a heating process, FPE-MDPF dispersion showed a stable behaviour during the cooling step (90 to 20°C) suggesting that the material could
be used in food system which requires heat tolerance