The effects of different baking methods on the textural, physicochemical and sensory properties, and in vitro antioxidant bioaccessibility of gluten-free muffins formulated with egg and various egg replacers

Abstract The growing demand for gluten-free and vegan bakery products has driven research into alternative formulations. This study developed novel gluten-free, vegan, and refined sugar-free muffins using tahini, dates, and carob, with chia, flaxseed, and psyllium as plant-based egg replacers. Muffins were prepared by steaming and oven baking, and their physical, nutritional, antioxidant, and sensory properties were evaluated. Steamed muffins showed significantly higher moisture (up to 14.10%) and water activity (Aw = 0.746) than baked samples (moisture as low as 1.70%, Aw = 0.444, p < 0.05). Baked muffins were firmer, with higher HMF (up to 81.60 mg/kg), lighter crust color (L = 34.49), and greater total color difference (ΔE = 25.9), while steamed samples were softer, darker, and exhibited higher browning index (BI = 70.2). Total phenolic content (TPC) and total antioxidant activity (TAA) were highest in baked chia muffins (TPC = 1258.19 mg GAE/100 g, FRAP = 212.27 µmol TE/g), though steamed muffins better preserved phenolics post-digestion. Sensory evaluation favored steamed flaxseed muffins (acceptability = 4.50/5), while baked psyllium muffins scored lowest. This is the first study to combine tahini, dates, carob, and multiple egg substitutes in steamed and baked muffins. Results highlight steam cooking and plant-based binders as effective strategies to enhance nutritional, antioxidant, and sensory qualities for health-conscious consumers.