Development and characterization of edible films based on chitosan, gelatine and gallic acid

Sukladno današnjim zahtjevima tržišta za smanjenom upotrebom plastičnih ambalažnih materijala, kao i visoko kvalitetnom hranom produženog roka trajanja, otvorili su prostor inovacijama u industriji pakiranja hrane. Cilj ovog rada bio je odrediti utjecaj galne kiseline, kao bioaktivnog sastojka, na fizikalno kemijska svojstva (boja, transparentnost, debljina, udio vode, topljivost te kapacitet bubrenja), barijerna svojstva (kisik, ugljikov dioksid i vodena para), antioksidacijska svojstva (ukupni polifenoli) te biorazgradivost filmova. Pripravljeni su filmovi na bazi kitozana i želatine (CSGEL) bez ili s dodatkom galne kiseline u koncentracijama od 1 % (m/v) (CSGEL1) i 2 % (m/v) (CSGEL2). Dodatkom galne kiseline zabilježen je značajan porast ukupnih polifenola, smanjen je kapacitet bubrenja te propusnost na vodenu paru kao i propusnost na UV zračenje. No, dodatak galne kiseline značajno je oslabio barijerna svojstva filmova na plinove (O₂ i CO₂) te je produžio vrijeme biorazgradnje u komercijalno dostupnoj zemlji.Due to the great commercial interest in reducing the use of single-use plastics, as well as need for high-quality food with extended shelf-life, made great openings for innovations in food packaging industry. The aim of this work was to determine the influence of gallic acid, used as bioactive compound on physic-chemical (colour, transparency, thickness, water content and swelling), barrier (oxygen, carbon dioxide and water vapour), antioxidant (total phenolic content) properties together with biodegradability character. Chitosan and gelatin films were made without or with the addition of gallic acid in concentrations of 1 or 2 % (w/v) (CSGEL1 and CSGEL2, respectively). The addition of gallic acid resulted in the significant increase in total phenolic content, lower swelling, water vapour permeability and better UV blocking property. However, the addition of gallic acid significantly has impacted the gas barrier properties (O₂ and CO₂) and increased the degradation time in the commercial soil