Background: The growing global population has increased the demand for sustainable, nutrient-dense protein sources. Lucerne (Medicago sativa) seeds are rich in protein and bioactive compounds, and Lactobacillus fermentation is known to enhance the nutritional properties of legumes. This study aimed to evaluate the effect of incorporating flours milled from unfermented or fermented lucerne seeds into bakery products (cookies and bread) on phytochemical content, antioxidant activity, protein digestion, and proximate composition.

Methods: Lucerne seeds were fermented using L. casei , and flours were prepared from unfermented and fermented seeds. Two replicates of cookies and breads were formulated by partially replacing wheat flour with fermented and unfermented lucerne flour (30% substitution). Both fermented and unfermented flour-based products were analysed for total phenols, flavonoids, and antioxidant activity (DPPH and ABTS assays) using colorimetric assays. The degree of protein hydrolysis (DH%) was determined for the baked products using the OPA assay by quantifying free and total amino groups. In addition, proximate composition was analysed using AOAC protocols.

Results: Incorporation of lucerne flour enhanced the nutritional and functional properties of the baked products. Crude protein content increased by approximately 55% in bread and 41% in cookies following both fermented and unfermented lucerne flour incorporation. Total phenols increased (P<0.05) two to three-fold compared to the control, while antioxidant activity increased four-fold in baked products that incorporated fermented or unfermented lucerne flour. Similarly, DH% increased by 31 and 131% in bread made with unfermented and fermented lucerne flour, respectively. A similar trend was observed in cookies, where incorporation of unfermented flour increased DH by 5%, while fermented flour resulted in a 29% increase. In addition, the fermented lucerne flour products had significantly higher (P<0.05) total phenols, antioxidant activity, and DH% compared to the unfermented lucerne flour products.

Conclusion: Flour made from fermented lucerne seeds is a highly effective functional ingredient for baked products, substantially enhancing crude protein content, total phenols, antioxidant activity, and protein digestion. Its incorporation into widely consumed foods represents a practical strategy to improve dietary protein intake and support sustainable nutrition in response to the growing global population. Future work to assess the sensory properties and consumer acceptability of these products is therefore warranted.