Microbial γ-polyglutamic acid (γ-PGA) incorporation into muffins: Impact on physico-chemical, functional, and textural properties

This study investigated the effects of gamma‐( γ )‐polyglutamic acid ( γ ‐PGA) on the physical, structural, and sensory properties of muffins. γ ‐PGA polymer, extracted from Bacillus valezensis M‐E6, was incorporated into muffin batter at concentrations ranging from 0.2% to 1%. The volume index of muffins was increased to 104 with γ ‐PGA (0.6%) compared to the control muffins (without γ ‐PGA, 95.3). Textural profile analysis revealed the best texture for muffins containing 0.6% γ ‐PGA, characterized by the lowest hardness (1508 g), which was half that of muffins without γ ‐PGA, along with improved cohesion and springiness. The viscosity of control batter was 12648 mPa·s, whereas for γ ‐PGA batter, it was 14845 mPa·s. Also, a decrease in lightness (L*) and an increase in redness (a*) were observed in muffins with γ ‐PGA. γ ‐PGA muffins received higher overall acceptability scores than the control in the sensory evaluation. The antioxidant activity of the muffin increased from 6% to 41% when incorporated with γ ‐PGA, which makes it a functional muffin. Incorporating γ ‐PGA improved the physical, textural, and sensorial properties of muffins, making it a promising natural ingredient for enhancing the quality and shelf life of baked products. These results suggest that γ ‐PGA not only improves the texture and quality of muffins but also benefits moisture retention and shelf life, aligning with consumer preferences for natural and sustainable food ingredients.