Abstract: Background and Objective: The objective of the present study was to characterize polyphenol-enriched extracts from industrial plant by-products (strawberry press residues) and to investigate the effect of the addition of these extracts on the growth and activity of yogurt starter culture. Materials and Methods: Polyphenol-enriched extracts from strawberry press residues (SPE) were obtained by adsorption technology. The total polyphenol and total monomeric anthocyanin content of the extracts and the yogurt samples were determined. Anthocyanin identification and quantification was performed using UHPLC-DAD. The total antioxidant capacity was evaluated using DPPH-(2,2 diphenyl 1 picryl hydrazyl hydrate) radical and FRAP-(ferric reducing antioxidant power) assays. Results: The SPE was characterized by high total polyphenol content (46400.0±23.93 mgGAE.100 g–1 dry extract), high total monomeric anthocyanin content (5901.25±0.011) and high antioxidant activity (DPPH = 2427±5.00 μmol TE g–1 and FRAP = 1664±1.77 μmol TE g–1). Four main anthocyanin groups were identified in the extracts: cyanidin 3-glucoside, pelargonidin 3-glucoside, pelargonidin 3-rutinoside and pelargonidin 3-malonoyl glucoside. The growth and acidification activity of the probiotic lactic acid bacteria were not affected by the enrichment of milk with polyphenol extracts. Conclusion: The results reported in the present study indicated that polyphenol-enriched extracts from industrial plant by-products (strawberry press residues) could be considered relevant sources of bioactive compounds. They also proved to be an interesting choice for improving the functional characteristics of probiotic yogurts.