Fermented Sargassum-Based Seafood Rice Seasoning: Prototype Development and Mix Design Optimization

Abstract

Direct incorporation of brown-seaweed biomass into foods is limited by its fibrous texture and by the challenge of retaining desirable marine and umami notes without an excessive fishy odor. This study evaluated whether fermented commercial Sargassum spp . biomass could be incorporated into a dry seafood seasoning for rice and whether a constrained mix design could identify a formulation with high preliminary hedonic acceptability.Commercial dried Sargassum spp . biomass was rehydrated for 6 h, washed, pretreated with 1.5% sodium bicarbonate  at 90–100°C for 2 h, reduced to 1–2-mm fragments, and fermented with a mixed lactic starter containing Companilactobacillus farciminis and Lactiplantibacillus pentosus . The fermentation involving 2.15% starter culture and 5.0% sugar lasted for 86 h at 30°C. The methods of hot-air, low-temperature, and freeze drying were compared using moisture content and handl- ing attributes. Seven variable ingredients were optimized within predefined ranges in an 18-run constrained mix design comprising 15 unique formulations. The response was the mean overall hedonic score for each run, based on evaluations by 30 assessors on a nine-point scale.The fermented biomass had a pH of 4.56 ± 0.05. The freeze-drying processing at −50 ± 2°C for 40 h yielded material with 4.51 ± 0.20% moisture and a crisp, loose, non-clumped structure. It was selected on the basis of handling properties. The drying routes were not compared by nutrient or volatile retention. The first-order mix model was significant (F = 45.40,  p < 0.001, R² = 96.12%, adjusted R² = 94.00%). The selected formulation comprised 30% fermented seaweed biomass, 10%   Porphyra/Pyropia -type dried red seaweed, 10% dried tuna, 5% dried shrimp, 25% roasted sesame, 10% mung bean, 5% carrot, 3% sugar, and 2% sodium chloride. The observed acceptability score was 8.30 ± 0.54 versus a predicted score of 8.43.  The final product contained 4.64 ± 0.30% moisture, 28.50 ± 1.58% protein, 15.30 ± 0.32% total ash, and 15.00 ± 0.64% lipid on an as-received basis.The sequential combination of fermentation, drying-route selection, and constrained mix optimization demonstrated the feasibility of the tested prototype and identified a formulation for independent confirmation. Because the selected solution lay on several formulation bounds, it represents the most favorable region within the tested domain rather than a universal optimum. The evidence was limited to preliminary hedonic testing and did not establish nutrient retention, shelf-life stability, comprehensive food safety, health effects, or market-level acceptance.