Valorization of edible flowers as new food ingredients: nutritional and chemical characterization of petals and corresponding infusions

The consumption habits are becoming more diversified and directed towards more sustainable food options [1]. The range of plant species used for food is also becoming more varied, seeking to combine new ingredients with some potential health benefits that could improve the health of the consumers but also with a major importance in ecological sustainability [2]. In this study, the edible petals of Dahlia mignon (commercial seeds mixture), Rosa damascena ‘Alexandria’ and R. gallica ‘Francesa’ draft in R. canina, Calendula officinalis L. and Centaurea cyanus L. provided by the company RBR Foods (Portugal), were characterized in terms of macronutrients, energy value and individual profile of fatty acids and tocopherols (GC-FID and HPLC-fluorescence, respectively). The petals and respective infusions were further characterized regarding its composition in soluble sugars and organic acids (HPLC coupled to RI and DAD detectors, respectively). Carbohydrates were the most abundant macronutrients, followed by protein and ash. The polyunsaturated fatty acids predominated over saturated fatty acids, mainly due to the presence of linoleic acid. C. officinalis petals had the highest concentration of tocopherols, especially α-tocopherol. Fructose, glucose and sucrose were identified in all petals and infusions (Fig. 1). Rose petals and the infusion of calendula gave the highest levels of organic acids, mainly due to the presence of malic acid and quinic acids, respectively (Fig. 2).