The increasing global population and evolving dietary preferences demand sustainable and innovative food solutions. Edible filamentous fungi offer a promising protein source and are emerging as key ingredients in meat alternatives. This study investigates the quality and safety of Neurospora intermedia biomass (NIB), produced in a demo-scale bubble column reactor using grape marc (GM) and wine lees (WL) as cultivation media, and synthetic glucose medium (SYN) as a control. For submerged fermentation, GM and WL were used at 4% w/v and 50% v/v, respectively, whereas 1.5% w/v glucose was used for SYN. The NIB exhibited a complete amino acid profile, with notable levels of lysine (9.25-9.46%) and leucine (8.69-9.04%), and its lipid fraction was rich in unsaturated fatty acids-oleic (41.0-59.8%) and linoleic (19.7-33.9%), along with phosphorus (1097-2747 mg/100 g) and polyphenols (5.48-7.89 mg GAE/g). Overall, the proteomic analysis allowed the identification of more than 3000 proteins. Bioinformatic predictions identified potential allergens, which together accounted for only a minor fraction of the total protein mass. This study underscores NIBs grown on GM and WL as a functional and nutritious ingredient that has a rich and diverse protein profile with potentially low allergenicity. Additionally, it offers an innovative strategy that adds economic value to oenological by-products, reduces environmental impact, and promotes a circular bioeconomy.