The influences of different drying procedures on the nutritional contents and antioxidant activities of brown seaweed, Sargassum oligocystum Mont. (Sargassaceae)

Seaweed's high nutritional value and numerous medicinal properties have led to a gradual increase in its usage in feed and food products. Effective drying techniques are necessary to maintain their nutritional content. This study examines how the biochemical composition and antioxidant capacities of Sargassum oligocystum Mont. are affected by different drying techniques (sun, oven, and freeze drying). The significantly highest (P < 0.05) moisture, protein, lipids, and fiber contents were conserved by freeze drying. The significantly highest (P < 0.05) amounts of calcium, magnesium, potassium, and sodium were maintained by freeze drying. Moreover, the lowest Na/K ratio was obtained by freeze drying. In comparison to oven (81.263%) and sun (75.979%) drying, freeze drying had the substantially greatest (P < 0.05) total amino acid content (86.544%). The composition of fatty acids differed substantially (P < 0.05), with freeze drying having the significantly highest levels of monounsaturated and polyunsaturated fatty acids. In terms of antioxidant parameters, freeze drying surpassed oven and sun drying, yielding the most phenolic content (62.994 mg GAE/g), flavonoid content (46.151 mg QE/g), and antioxidant activities. According to the results, freeze drying is the best way to maintain Sargassum oligocystum 's nutritional and antioxidant qualities, which makes it the drying method of choice for medicinal and nutritional food applications.