Characterization of two prickly pear species flowers growing in Tunisia at four flowering stages

•The flowers of Opuntia present a rich nutrient composition during flowering.•The techno-functional properties revealed that flowers can be considered as a source of dietary fiber.•Opuntia flowers can be an excellent source of foods supplements.

Opuntia flowers belonging to two species of prickly pear were evaluated at four flowering stages: vegetative, initial flowering, full flowering and post-flowering stage, for possible use as a potential source in the food enrichment. Chemical composition including moisture, ash, protein, fat, soluble sugars, total fibers, mineral amounts and fatty acid profiles of Opuntia ficus-indica and Opuntia stricta flowers were investigated. Functional properties (swelling capacity (SWC), water holding capacity (WHC), water solubility index (WSI) and oil holding capacity (OHC)) were also studied. Results showed that during the maturation of flowers, there is a decrease in protein contents whereas fat contents increase, for both species. High minerals amounts were noticed in Opuntia flowers and they can be considered as an excellent source of minerals. The fatty acids profiles were dominated by the palmitic acid (38-59%). The techno-functional properties (SWC, WSI, WHC and OHC) were found to be important and they can be modulated according to the temperatures. Owing to its chemical profile and functional properties, Opuntia flowers could be used as an ingredient to improve different physical and nutritional properties of foods.