Optimization of gluten-free functional noodles formulation enriched with fish gelatin hydrolysates

The optimal formulation of gluten-free functional noodles (GFN) based on rice (70%) and cassava (30%) flour enriched with gelatin hydrolysates was studied. The effect of pregelatinized flour (rice: cassava, 70:30) (X-1, 10-30%), fish gelatin hydrolysates (X-2, 1-5%) and transglutaminase (X-3, 0.1-1.0%) on physiochemical, functional and sensory properties of GFN were evaluated by using a response surface methodology (RSM) with Box-Behnken design. The results showed that a quadratic equation was appropriate for all models with high R-2 values (0.90-0.98). Optimum conditions for X-1, X-2 and X-3 were 20.5, 5.0 and 0.25%, respectively. The optimized GFN had a 1.16 mm thickness, 24% cooking loss, 279% cooking weigth, 179% water absorption, and 0.19 N tensile strength. Antioxidative activities of GFN (IC50) were 0.57 g/mL for DPPH scavenging activity, 0.87 g/mL for ABTS scavenging activity and 0.01 mmol FeSO4/g for FRAP assay. Addition of fish gelatin hydrolysates resulted in GFN noodles with slightly rougher surface. Sensory properties lay in the range of like slightly to like moderately (6-7).