Application potential of sugar beet pulp pectin and various proteins in the formation of edible films

Cilj ovog rada bio je ispitati mogućnost proizvodnje jestivih filmova s pektinom izoliranim iz pulpe šećerne repe u kombinaciji s proteinima piskavice, riže, graška, soje, sirutke i badema. Filmovi su formulirani u ekstraktu žutog čaja kao izvoru bioaktivnih spojeva. Pektin iz pulpe šećerne repe ekstrahiran je hidrolizom s klorovodičnom kiselinom, a proteini iz piskavice izolirani su alkalnom hidrolizom i naknadnom precipitacijom pri izoelektričnoj točki, dok su ostali proteini komercijalni. Primarnim sirovinama (izolirani pektin, proteini) određena su fizikalna svojstva, a formuliranim filmovima ispitana su fizikalno-kemijska, mehanička i senzorska svojstva te bioaktivni sastav (ukupni i pojedinačni polifenolni spojevi, flavan-3-oli) i antioksidacijski kapacitet. Prema dobivenim rezultatima, čisti pektinski film pokazao je najbolja mehanička i senzorska svojstva, dok je film pripremljen kombinacijom pektina i proteina graška pokazao najlošija senzorska svojstva. Najbolja funkcionalna svojstva (udjel polifenolnih spojeva, antioksidacijski kapacitet) karakteriziraju jestive filmove pripremljene dodatkom proteina riže i badema.The aim of this study was to investigate the possibility of producing edible pectin films isolated from the pulp of sugarcane in use with proteins of fenugreek, rice, peas, soy, whey and almonds. Films are formulated in yellow tea extract as the source of bioactive compounds. Pectin from pulp of sugar beet was extracted by hydrolysis with hydrochloric acid, and proteins from fenugreek were isolated by alkaline hydrolysis and subsequent precipitation at the isoelectric point while other protein were commercially available. Physical properties are determined for the primary raw materials (isolated pectin, proteins) and the formulated films have physico-chemical, mechanical and sensory properties, as well as the bioactive composition (total and individual polyphenolic compounds, flavan-3-ol) and antioxidant capacity. According to the obtained results, pure pectin film showed the best mechanical and sensory properties while the film which was prepared from pectin and pea protein showed the worst sensory properties. The best functional properties (content of polyphenolic compounds, antioxidant capacity) characterize edible films prepared with the addition of rice and almond protein