Physicochemical and nutritional characteristics of an underutilised edible fern (Stenochlaena palustris) incorporated into a dates-based food matrix

Underutilised edible plants represent important but insufficiently characterised nutritional resources within plant-based food systems. Stenochlaena palustris is a wild edible fern widely consumed in Southeast Asia; however, its incorporation into formulated food matrices remains poorly documented. The objective of this study was to generate initial physicochemical and nutritional data for dates-based food formulations incorporating S. palustris powder at different inclusion levels, providing validated baseline compositional information on an underutilised edible fern within a contemporary plant-based food system. Dates-based energy bars were formulated with S. palustris powder at 2.5% and 5.0% (w/w), alongside a control formulation without fern inclusion. Proximate composition, sugar profile, mineral content, antioxidant activity, and selected physicochemical properties were determined using validated analytical methods by an accredited laboratory. Incorporation of S. palustris was associated with observed increases in dietary fibre, ash, and protein, with generally higher values of selected minerals, including calcium, magnesium, iron, and zinc, in the fortified formulations compared to the control, while total energy values remained comparable across formulations. Water activity values for all formulations were below 0.48, and total flavonoid content increased with higher fern inclusion, while DPPH antioxidant activity was highest in the control formulation. As each formulation was analysed as a single composite sample, the data are presented as baseline compositional observations.