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Cilj ovog rada bio je odrediti utjecaj dodatka vodenog ekstrakta ružmarina (Rosmarinus officinalis L.) (30 % v/v) na fizikalno-kemijska svojstva (boja, debljina, udio vode, topljivost, kapacitet bubrenja), barijerna svojstva (kisik, ugljikov dioksid i vodena para), sadržaj ukupnih polifenola, te biorazgradivost pripremljenih filmova na bazi kitozana (2 % m/v) i alginata (1,5 % m/v). Nadalje, ispitan je i utjecaj dodatka kalcijevih iona (Ca²⁺) s ciljem umrežavanja matriksa alginatnih filmova. Ekstrakt ružmarina korišten je kao prirodni antioksidans, izvor bioaktivnih sastojaka za pripremu jestive aktivne ambalaže za pakiranje hrane. Dodatak ekstrakta ružmarina utjecao je na smanjenje udjela vode i kapaciteta bubrenja te propusnosti na vodenu paru, a povećao se udio polifenola, topljivost filmova te propusnost na plinove (O₂ i CO₂). Umrežavanjem alginatnih filmova povećala im se propusnost na vodu, kapacitet bubrenja, topljivost, udio vode, sadržaj polifenola. Dodatak ekstrakta ružmarina i umrežavanje sa Ca²⁺ nisu imali značajan utjecaj na biorazgradnju filmova. The aim of this study was to determine the influence of rosemary water extract (Rosmarinus officinalis L.) (30% v/v) on physico-chemical properties (color, thickness, water content, solubility, swelling capacity), barrier properties (oxygen, carbon dioxide and water vapour), total polyphenols content and biodegradability of edible films made from chitosan (2 % w/v) and alginate (1.5 % w/v). Furthermore, the influence of cross-linking alginate matrix with calcium ions (Ca²⁺) on film properties was examined. Rosemary extract was used as a natural antioxidant, a source of bioactive ingredients for the preparation of edible films as active food packaging. The addition of rosemary extract resulted in decreased water content, swelling capacity and water vapour permeability, while polyphenol content, film solubility and permeability to gases (O₂ and CO₂) was increased. Cross-linking of alginate films increased their water vapor permeability, swelling capacity, solubility, water content, and polyphenol content. The addition of rosemary extract and/or crosslinking with Ca²⁺ ions did not have any significant effect on the biodegradation of tested films. |
