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The present work aimed to study the physicochemical characteristics and the functional properties of the male date palm sap (Phoenix dactylifera L.). The surface properties at the air-water interface were studied on the basis of the drop volume method. Foaming properties (foam capacity and stability) were evaluated using bubbling method by optical and conductimetric measurements (foamscan). Composition analysis revealed a high sugar content (92.29% w/w dry matter basis) with dominance of sucrose. Sap contains also 5.14% w/w of proteins and 2.57% w/w of ash. Proteins are probably the source of the surface activity and the observed foam power. At higher contents of dry matter, lyophilized sap solutions showed Newtonian comportment and improved surface activity and foam properties. Results present some interesting functional properties that suggest to deepen research particularly in sap proteins.

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This study is a contribution to valorise date palm sap (Phoenix dactylifera L.) by elaboration of high quality syrup. Sap was concentrated by evaporation and the obtained product was characterized by its physicochemical, rheological, thermal, sensory properties and by its antioxidant activity. Syrups from date palm sap have a good nutritional value marked by high amounts of sugars (58—75 g/100 g fresh matter basis), minerals (2.1—2.6 g/100 g fresh matter basis) and phenolics (147.61—224.55 mg of ferulic acid equivalents/kg fresh weight). Syrup also presents an antioxidant activity that appears related to total phenolic content. Rheological properties indicate that syrup preserves a Newtonian behavior from 10 °C to 55 °C well modeled by Arrhenius equation. Hedonic evaluation showed that consumers’ appreciation of date palm syrup was not significantly different to the most known sap syrup: maple syrup.