Effects of Deep-Frying and Hot-Air Drying on Nutritional and Quality Attributes of Catfish Powder-Fortified Instant Noodles

Instant noodles are among the most widely consumed convenience foods globally; however, their nutritional profile is limited in protein quality and essential fatty acids. The present study was aimed to evaluate the effects of catfish ( Clarias macrocephalus × Clarias gariepinus ) powder (CFP) at 10–30% (w/w) on instant noodles. Two processing methods, namely deep-frying and hot-air drying at 80°C, were compared for their effects on physicochemical, nutritional, textural, structural, flavor, and antioxidant properties. CFP was produced by hot-air tray drying at 120°C; noodle drying was conducted at 80°C. CFP incorporation significantly affected all quality parameters ( p <0.05). Lightness (L*) decreased progressively with increasing CFP levels. Water activity remained below 0.6 for ≤20% CFP fried samples; the 30% CFP fried sample reached a borderline value of 0.61. The degree of gelatinization decreased from approximately 71% to 47% at 30% CFP. Cooking loss in 30% CFP fried noodles reached 56.99%, a level considered commercially unacceptable owing to severe structural disintegration. Protein content increased by approximately 81% (fried) and 119% (dried), and lysine improved by approximately 104% at 30% CFP. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were introduced exclusively through CFP, reducing the n-6/n-3 ratio from approximately 40 to below 8. Textural properties decreased consistently with increasing CFP levels. Structural analyses confirmed progressive gluten network disruption and reduced starch crystallinity. Volatile compound profiles shifted toward protein-derived aroma compounds, and antioxidant capacity increased significantly. Overall, 10% CFP provided the optimal balance between nutritional enhancement and product quality and is recommended for commercial application, while 30% CFP showed commercially poor cooking quality due to improper cooking behavior and structural integrity. Future work should incorporate formal sensory evaluation and the application of hydrocolloids or binding agents to improve structural integrity at higher CFP substitution levels.