Powder Properties of Spray-Dried Cydonia oblonga Mill. (Quince) Seed Mucilage: A Novel Natural Biopolymer with Functional Excipient Characteristics

Background: Powdered mucilages are increasingly being used as natural excipients in pharmaceutical formulations, functioning as binders, disintegrants, thickeners, suspending agents, and film formers. Their swelling, viscosity-enhancing, and biocompatible properties also make them useful in controlled-release systems and tablet production. This study aimed to produce spray-dried Cydonia oblonga (CO) mucilage, examine how drying parameters influence yield, and determine its physicochemical and rheological characteristics to evaluate its suitability for pharmaceutical applications. Methods: Powdered CO mucilage was obtained by spray drying. The obtained powders were characterized on yield, particle size and morphology, moisture content, loss on drying, flow properties and swelling index. Results: The obtained powders show yields of 10.6–16.4%, particle sizes of 4.5–5.39 μm, and moisture contents of 2–3%. Their flowability is limited despite satisfactory angle of repose, Hausner ratio, and Carr index values, yet all powders exhibit excellent swelling properties. Conclusions: Model CM6 of the obtained powdered CO seeds hydrocolloid stands out as the best spray-dried hydrocolloid, combining high drying efficiency, low residual moisture, uniform particle formation, and excellent swelling capacity despite its limited flowability. These properties make it a strong candidate for use as a biopolymer or excipient in pharmaceuticals.