Ohrid, Macedonia
Skopje, Macedonia
Skopje, Macedonia
Edirne, Turkey
Čačak, Serbia
Belgrade, Serbia
Functional beverages enriched with herbal extracts are gaining popularity due to their potential health benefits. Tilia cordata flowers are known for their antioxidant and antimicrobial properties, making them a promising additive in food and beverage formulations. Our study aimed to develop ready-to-drink iced teas enriched with T. cordata flower extracts and to evaluate their antioxidant, antimicrobial, and sensory characteristics as functional food products. Fresh T. cordata flowers were analyzed for metal contents. Phenolic acid profiles in ethanolic and aqueous extracts were determined using HPLC-MS. Antioxidant activity was evaluated using DPPH radical scavenging, conjugated diene, and iron ion chelation assays. Antimicrobial effects were tested against Staphylococcus aureus, Bacillus cereus, and Listeria monocytogenes. Sensory analysis was conducted using AI-based facial expression recognition to assess consumer responses. Metal analysis revealed low concentrations of Mn, Zn, Cu, and Fe, with no detectable Pb, Cd, or Ni. Ethanolic extracts showed significantly higher levels of phenolic acids than aqueous extracts. Iced teas containing both types of extracts demonstrated strong antioxidant activity, with ethanolic formulations having the highest levels of phenols and flavonoids. Antimicrobial tests confirmed activity in both teas, with ethanolic extracts showing stronger effects. Sensory analysis indicated positive emotional responses and consumer acceptance for both formulations. Iced teas enriched with T. cordata extracts exhibited significant antioxidant and antimicrobial properties, confirming their potential as functional beverages. The use of AI-driven sensory evaluation proved effective in capturing consumer preferences, supporting its application in product development. These findings suggest commercial viability for industrial production.
medicinal iced tea, Tillia cordata, functional beverages, natural plant extracts, AI sensory evaluation
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