SummaryThis study explored the replacement of alkaline phosphate (AP) with flaxseed cake (FC) in mortadella, assessing the impact on technological, oxidative, microbiological, and sensory properties. The inclusion of FC proved promising in maintaining emulsion stability, cooking loss, and water‐holding capacity and did not significantly affect colour characteristics, as indicated by the ΔE values (<5). Sensory analysis validated the substitution, highlighting the absence of a sandy texture sensation and FC's ability to suppress sensory defects caused by the removal of AP. However, adding FC decreased texture parameters such as hardness and cohesiveness, which can be leveraged in formulating products for specific niches, like older adults. Adding FC did not favour mesophilic aerobic and lactic acid bacteria growth. Nevertheless, the TBARS values of the mortadellas with FC increased (peaking at 0.5 mg MDA kg−1), but the sensory detection limit was not reached even at the end of storage.