Integrating Marine and Agro-Waste Biopolymers in Functional Syrup Formulation: Optimization of Fucoidan–Pectin Composite from Brown Seaweed and Watermelon Albedo

Developing functional food products from sustainable bio resources has gained growing interest, particularly in addressing lifestyle-related diseases such as dyslipidemia. This study aimed to formulate and optimize a composite syrup incorporating pectin extracted from watermelon (Citrullus lanatus) albedo and fucoidan isolated from brown seaweed (Sargassum crassifolium), two biopolymers with known lipid-lowering potential. Three formulation ratios of pectin to fucoidan (66.67:33.33, 83.33:16.67, and 100:0) were evaluated for their effects on the syrup’s physicochemical (viscosity, total dissolved solids, pH, colour) and sensory (taste, texture, colour, and overall acceptability) properties. The results showed that increasing pectin content significantly enhanced viscosity and pH (p<0.05), while higher fucoidan content increased total dissolved solids and altered the colour profile. Sensory evaluation revealed that the formulation containing 83.33% pectin and 16.67% fucoidan achieved the highest overall acceptance (p<0.05). These findings highlight the potential of integrating agro-waste and marine-derived biopolymers in a functional syrup matrix, offering a sustainable and consumer-acceptable candidate for nutraceutical development. Nevertheless, the present study is limited to physicochemical and sensory assessments; further investigations on bioactivity, nutritional profile, microbiological stability, and long-term storage are required to substantiate its efficacy and practical application.