Sustainability in the food chain and the prevention of food losses is an issue of increasing importance. There is a large number of processing by-products where innovative strategies are helpful for transferring these losses into a consumable state. In a step-by-step approach, this current study focused on the sensory properties of blends of sunflower press cake and whey, fermented with different consortia of microorganisms and intended for being used as a basis for a savory spread. In the first part of the work, blends fermented with six co-cultures from lactic acid bacteria and yeasts were characterized by free choice profiling and quantitative descriptive analysis. The respective results were used to modify the formulation and to select the fermentation cultures that were promising from a sensory point of view. Subsequent investigations allowed reducing sample dimensionality further, and the study was concluded by affective hedonic tests and a check-all-that-apply set-up performed by consumers. The final experiment also comprised a just-about-right approach performed for specifically evaluating spreadability. The outcome of the entire study indicates that it is possible to tailor attractive foods from by-products, provided that the need for final optimizations regarding palatability is considered.

Growing environmental and food security concerns have increased interest in circular strategies to valorize agri-food by-products. Sunflower-seed press cake (SSPC), a protein-rich residue from oil extraction, is largely underutilized despite its high nutritional and functional value. This study aimed to develop a fermented plant-based food prototype (PBFP) from SSPC using Lactococcus lactis B12 and Penicillium camemberti, evaluating microbiological safety, chemical characteristics, and sensory acceptability. A blend containing 40% SSPC and 60% water was autoclaved, inoculated, and ripened for 4 weeks under controlled temperatures. Microbial counts, pH evolution, free amino acids, biogenic amines, volatile organic compounds (VOCs), cyclopiazonic acid (CPA) content, and sensory attributes were evaluated using cultural techniques, HPLC, HS-SPME/GC-MS, LC–ESI–MS/MS (QTRAP 4000), and sensory evaluation. L. lactis efficiently acidified the matrix (pH ≈ 4.5–4.9), ensuring microbial food safety, with high LAB counts (~10⁹ CFU/g) and absence of pathogens (Listeria monocytogenes and Salmonella spp.) and hygienic markers < 2 log CFU/g (B. cereus, E. coli, and Enterobacteriaceae). Free amino acids decreased during fermentation, and no histamine or tyramine was detected. VOC analysis revealed diacetyl, acetoin, 2,3-butanediol, and 1-octen-3-ol, contributing to mild dairy-like notes. CPA was detected at 0.48 ng/g, well below levels reported in cheeses. Sensory evaluation showed no significant differences in overall intensity between inoculated and control blends, although qualitative descriptors indicated subtle changes in aroma and texture. These results demonstrate the feasibility of safely producing a fermented plant-based prototype from SSPC. Future studies should explore longer ripening times, additional microbial consortia, and strategies to enhance texture and aroma complexity.