Characterization of physicochemical and functional properties of gluten-free keto flours for cookie production

This study investigated the physicochemical, functional, textural, and sensory properties of composite gluten-free keto flours (KF) and their application in cookie production. Two flour blends were formulated: KF1 (50% coconut, 15% almond, 5% moringa, 15% dried pea, 15% watermelon seed) and KF2 (40% coconut, 15% almond, 5% moringa, 20% dried pea, 20% watermelon seed), compared against a control made with 100% refined wheat flour. Proximate analysis revealed that keto flours contained significantly higher protein (KF1: 21.07%, KF2: 22.90%), fiber content (KF1: 10.70%, KF2: 8.45%) and fat (KF1: 18.12%, KF2: 20.96%) compared to wheat flour (protein: 12.7%, fiber: 0.84%, fat: 1.93%). KFs also showed higher water absorption capacity (KF1: 303.8%, KF2: 281.4%, control: 72%), oil absorption capacity (KF1: 181.6%, KF2: 192%, control: 87.2%), and foaming stability (KF1: 94.5%, KF2: 91.99%, control: 10.01%). Cookies prepared with keto flours showed lower carbohydrate content (KF1: 15.52%, KF2: 13.30%) and higher energy values (KF1: 628.33 kcal, KF2: 640.14 kcal) compared to control cookies (495.85 kcal). Texture analysis indicated reduced hardness in keto cookies, while sensory evaluation revealed KF2 cookies as most acceptable among panelists. FTIR analysis further revealed characteristic aliphatic C–H stretching, carbonyl (C = O) ester bands, and carbohydrate-associated C–O/C–O–C vibrations, confirming the presence of lipid- and carbohydrate-rich structures that corresponded with the enhanced fat binding, moisture retention, and textural properties of keto cookies. These findings establish composite keto flours as effective alternatives to wheat flour in cookie formulations, offering enhanced functional properties and acceptable sensory quality.