This study presents the development and evaluation of a novel infant formula (IF) derived from goat milk and fortified with plant-based proteins (rice and pea isolates), aiming to address allergenicity and enhance bioactivity compared to conventional bovine and commercial IFs. The formulation was designed to mimic the macronutrient profile of human milk, comprising 16% protein, 45% carbohydrate, and 39% fat, with added micronutrients per USDA guidelines. Simulated infant gastrointestinal digestion (SIGID) was employed to assess protein digestibility, antioxidant capacity, and anti-inflammatory potential.

The goat milk-based IF fortified with 10% rice protein isolate (GMIF-10%R) exhibited the highest degree of hydrolysis (DH: 3125.4 μg NH₃/g), surpassing both commercial IF (CIF: 1287.6 μg NH₃/g) and bovine IF (BIF: 1102.3 μg NH₃/g). SDS-PAGE and RP-UPLC analyses confirmed extensive protein breakdown and diverse peptide generation in GMIF-10%R post-digestion. Fluorescence microscopy revealed uniform protein and lipid dispersion, with reduced coagulum formation compared to bovine IF.

Bioactivity assays demonstrated superior antioxidant activity in GMIF-10%R (ABTS: 10,245 μM TEAC; DPPH: 7,890 μM TEAC) and enhanced anti-inflammatory response (Diclofenac sodium equivalent: 7,980 μg/mg protein) following SIGID. Notably, plant protein fortification contributed to improved emulsification and reduced allergenic potential, as evidenced by the absence of β-lactoglobulin and lower particle aggregation. These findings suggest that goat milk combined with plant-based proteins offers a promising alternative for hypoallergenic infant formula with enhanced digestibility and bioactive properties. Further in vivo studies are warranted to validate its clinical efficacy and safety.