Nutritional, Structural and Rheological Assessment of Cookies Supplemented with Lutonarin and Saponarin from barley ( Hordeum vulgare L.) crop

Abstract

Barley (Hordeum vulgare L.) is a nutrient-rich cereal crop and a valuable source of bioactive compounds, particularly flavonoids such as lutonarin and saponarin, which possess strong antioxidant and health-promoting properties. This study evaluated the nutritional, structural, rheological, and sensory properties of cookies enriched with barley flavonoids. Initially, the nutritional composition of barley leaves was analysed, including moisture (10.4±0.09%), ash (3.02±0.07%), protein (23.62±0.23%), fat (4.95±0.05%), crude fiber (13.25±1.25%), total carbohydrates (44.76±2.07%), and antioxidant activity (DPPH: 69.10±1.92%, FRAP: 16.18±0.12 μmol Fe2+ equiv/g, ABTS: 7.07±0.25 mg TEAC/g, total phenolics: 0.125±0.05 mg GAE/g, total flavonoids: 0.46±0.03 mg GAE/g). In the second phase, lutonarin and saponarin were extracted and incorporated into wheat flour for cookie development. In the final phase, cookies with varying flavonoid concentrations (T0–T4) were analysed. Farinograph results indicated increased water absorption, dough development time, and stability. FTIR, SEM, and XRD confirmed flavonoid-induced molecular interactions, producing a more porous structure, while textural analyses showed reduced hardness and chewiness. Colour parameters (L*, a*, b*) indicated darker, richer hues with higher flavonoid content due to phenolic and Maillard reactions. Sensory evaluation revealed high consumer acceptance, with T2 and T3 showing optimal antioxidant activity, nutritional value, dough behaviour, and sensory qualities.