Innovative Active Edible Coating with Safflower (Carthamus tinctorius L.) Extract for Microbial Inactivation and Shelf Life Extension of Cheese

Edible coatings enriched with bioactive compounds represent a sustainable alternative to synthetic preservatives, offering both microbial safety and extended shelf life. This study introduces an active edible coating system based on whey protein isolate (WPI) incorporating safflower ( Carthamus tinctorius L. ) flower extract, applied for the first time in the preservation of Malatya cheese. The formulation contained WPI, glycerol, guar gum, and varying concentrations of safflower extract, and was applied by immersion. Antioxidant capacity was determined using the DPPH radical scavenging assay, while antimicrobial activity was evaluated through minimum inhibitory concentration (MIC) and disk diffusion methods. Coated and uncoated cheese samples were stored at + 4°C and + 20°C for 21 days, and microbial counts were monitored relative to the 5 log CFU/g safety threshold.Safflower extract showed strong antioxidant activity (92.9% DPPH scavenging) and moderate antimicrobial activity (MIC 5000 ppm). Cheese samples coated with safflower-enriched formulations, particularly EC4, maintained microbial counts below the safety threshold under refrigeration, whereas uncoated samples exceeded this limit within 7 days. FTIR, TGA, and DSC analyses revealed hydrogen bonding and improved stability of the coating matrix, suggesting gradual release of bioactive compounds.In conclusion, safflower-enriched coatings function as innovative active packaging materials by combining antimicrobial and antioxidant effects to improve microbial safety and extend cheese shelf life. Although the antimicrobial efficacy of safflower extract was moderate, this first report highlights its potential as a natural preservative and suggests future optimization for industrial application.