Effects of drum drying on the nutritional composition, proteomic profile, and functional properties of Wolffia...

Plant-based proteins are increasingly valued as sustainable alternatives to animal-derived sources, with Wolffia globosa standing out for its high protein content. However, the effects of processing on its nutritional and functional characteristics are limited. This study aimed to investigate the proteomic profile and effects of drum drying on its physiochemical, nutritional and functional properties, providing key insights for product development.

Drum drying at 120 °C and 150 °C effectively reduced the moisture content to below 50 g kg^-1, with protein concentrations of 320-340 g kg^-1 dry weight (DW). Proteomic analysis identified 342 proteins, including ribulose-1,5-bisphosphate carboxylase oxygenase (RuBisCO), adenosine triphosphate (ATP) synthase, and antioxidant enzymes, reflecting its photosynthetic activity and functional potential. Microscopic observations confirmed the preservation of key microstructures (cell wall integrity and trichomes), supporting improved rehydration and powder flowability. All essential amino acids were retained in dried samples, and the antioxidant activities increased after post-drying. In vitro protein digestibility improved from 81% (fresh) to 85% (dried). In extrusion trials, the addition of W. globosa powder (25 g kg^-1) under low-moisture and moderate screw-speed conditions produced extrudates with the highest expansion and lowest density.

Moderate drum drying enhanced the structural, nutritional and functional qualities of W. globosa powder. The incorporation into extruded products supports its potential as a sustainable and protein-rich ingredient. © 2025 Society of Chemical Industry.