Physico-Chemical Characterization of Tunisian Canary Palm (Phoenix canariensis Hort. Ex Chabaud) Dates and Evaluation of Their Addition in Biscuits

Phoenix canariensis Hort. Ex Chabaud, also known as the Canary Island palm or ornamental palm, is an endemic species of the Canary Islands and has been widely propagated globally. It has become one of the most important and appreciated ornamental plants, especially in the Mediterranean climate. The fruits are edible but used only for feed as they are bitter. Despite its diffusion, not much data on the composition of these fruits and their application as food are available. The aim of this study was to define the chemical characteristics, especially those of the polyphenolic constituents, of red and yellow varieties of Canary palm dates, and to evaluate their use alone or in different mixes in biscuit production. The yellow variety had higher quantities of fiber (36.88% DW (Dry Weight)) and polyphenolic compounds, while the red variety had a high content of sugars, mainly glucose (22.8% DW). Epicatechin is the most important polyphenol of dates (562 g/g DW). The use of date palm powder on biscuit production resulted in an increase in hardness, polyphenol and fiber content, and antioxidant activity. Sensory analysis showed that the biscuits obtained with a 25/75 mix of red/yellow date powder had the most overall liking.