Functionalization of polyethylene foils using biopolymers for the development of active packaging

Vse večja zdravstvena in ekološka ozaveščenost ljudi je pripeljala do zmanjševanja uporabe aditivov in konzervansov v živilih. Zato se vse več uveljavlja aktivno in inteligentno pakiranje. Le-ta namreč ne zagotavlja le fizične zaščite, temveč omogoča daljši rok uporabe, varnost, kakovost in preprečuje možnost zunanje kontaminacije. V magistrski nalogi sem se ukvarjala z metodo za izboljšanje lastnosti polietilenske (PE) folije, primerne za uporabo v embalaži živil. Nanaša se na adsorpcijo dveh formulacij, in sicer formulacijo hitozana z ujetim ekstraktom grenivkinih pečk ter na formulacijo proliposomov z ujetim ekstraktom grenivkinih pečk, na površine PE folij. Metoda gravimetrije in infrardeče spektroskopije (FTIR) kažejo na uspešno vezavo obeh formulacij na folije. Poleg tega sta obe formulaciji zmanjšali prepustnost kisika in s tem zvišali barierne lastnosti folij. Prav tako se je stični kot, ki kaže na dobre protikondenčne lastnosti folije. Poleg navedenih uporabnih lastnosti kažejo funkcionalizirane folije protimikrobne in antioksidativne potenciale, vendar bi bilo za učinkovite inhibicije potrebno zvišat količino nanosa ali optimizirati tehnologije nanosa. S pomočjo SEM analize smo ugotovili, da gre za zelo neenakomeren nanos na površini folij, kar lahko vpliva na antioksidativni in protimikrobni potencial negativno in bi ga bilo možno izboljšat z kisikovo plazemsko aktivacijo. Prišla sem do zaključka, da metoda kaže dobro izhodišče za optimizacijo procesa, ki bi lahko kasneje izkazal tudi potencialno uporabo kot pakirni material v živilski industriji.The increasing health and environmental awareness of people has led to a reduction in the use of food additives and preservatives. Therefore, active and intelligent packaging is gaining ground. It not only provides physical protection but also provides a longer shelf life, safety, quality and prevents the possibility of contamination from the outside. In my master\u27s thesis, I was dealing with a method for improving the properties of polyethylene (PE) polymer foils suitable for applications in food packaging. It relates to the adsorption of two formulations, namely the chitosan formulation with trapped grapefruit extract and the formulation of proliposomes with trapped grapefruit extract on the surfaces of PE foils. The method of gravimetry and infrared spectroscopy (FTIR) method shows successful binding of both formulations onto foils. In addition, both formulations reduced oxygen permeability and wetting contact angle, which indicates good anti-fog foil properties. Beside listed applicable properties, functionalized foils possess antimicrobial and antioxidative potentialsbut the amount of application should be increased. The use of SEM analysis shows that I had a very uneven coating, which could be improved by oxygen plasma activation. I came to the conclusion that the method, with a more uniform application, would be useful in various packaging applications, such as active packaging in the food industry