Optimisation of <italic>Eucommia ulmoides</italic> Leaf Micro-powder Shortbread Biscuit Formulation and Quality Enhancement

Objective: The study aimed to develop a nutritionally rich Eucommia ulmoides leaf micro-powder shortbread biscuit with enhanced taste and unique flavor to cater to the demand in the health food market. Methods: Fuzzy mathematical comprehensive evaluation method and response surface test were used to optimise the biscuit formulation, and the optimal process formulation and baking conditions were determined using 100 g of low gluten flour as the benchmark. The superiority of the formulations was verified through multidimensional comparative analyses of sensory evaluation, textural properties, microstructure, nutrients, antioxidant capacity and volatile flavour substances. Results: Comparative analysis with a blank formulation (lacking Eucommia ulmoides leaf micro-powder) revealed that the optimized formulation exhibited significantly improved sensory evaluation, enhanced textural attributes including hardness, crispness, and chewiness, a notably higher porosity of 50.91%±0.71%, a reduced spreading ratio of 4.99±0.12, and decreased baking loss of 18.94%±0.23%. The nutrient composition analysis revealed an increase in total flavonoid content from 5.03±0.07 mg/mL to 6.61±0.03 mg/mL, total phenol content from 0.64±0.02 mg/g to 1.53±0.03 mg/g, and sodium cholate adsorption capacity from 16.06±0.48 mg/g to 21.17±0.53 mg/g. Furthermore, enhancements were observed in DPPH, ABTS+, hydroxyl radical scavenging, and ferric ion reduction capacities (PEucommia ulmoides leaf micro-powder can effectively enhance the textural properties, antioxidant properties and flavour of shortbread biscuits under the optimized process formulation and baking conditions.