FOOD. Science. Technology. Quality

Food. SCIENCE. Technology. Quality

Food. Science. TECHNOLOGY. Quality

Food. Science. Technology. QUALITY




Effect of selected polysaccharides on physicochemical propetrties of edible films produced on the basis of pea proteins


The effect of the addition of carboxymethylcellulose (in three viscosity types: CMC 30, CMC 1000, CMC 10000), hydroxypropylmethylcellulose (HPMC), pectin (PEK), and chitosan lactate (MCH) on the properties of pea protein films was investigated. The films were prepared from 10 % w/w pea protein isolate solutions containing plasticizers, 4 % w/w of glycerol or 5 % of sorbitol, and 0.25 or 0.5 % w/w of polysaccharides. The solutions were poured so as to form a thin layer and they were dried. The films were physically and chemically analysed, i.e. their moisture content, solubility of dry matter, water vapour permeability (WVP), light transmission, transparency were measured as was their colour using a CIE L*a*b* system. Based on the viscosity measurements of the filmogenic solutions, it was proved that, with the exception of MCH, the addition of polysaccharides contributed to a significant increase in this parameter. The functional properties of films largely depended on the type of the plasticizer used. Compared to the sorbitol-plasticized films, the films with glycerol were characterized by a moisture content that was almost doubled, a lower solubility, and a WVP value that was more than ten times higher. The range of changes caused by the incorporation of individual polysaccharides depended on their concentration rate as well as on the type of the plasticizer used. The addition of 0.5 % of MCH made it impossible to obtain coherent films with the use of sorbitol as a plasticizer. It was found that the addition of polysaccharides did not change the moisture content of films plasticized with glycerol, however, it reduced the moisture content of films containing sorbitol. Moreover, the addition of polysaccharides did not affect the WVP value of films plasticized with sorbitol, and, in the case of the films with glycerol, it was found possible to decrease and to increase the WVP value. The addition of HPMC and MCH increased the solubility of glycerolplasticized films. All the analyzed films were characterized by a high barrier against UV radiation. The presence of polysaccharides considerably reduced the visible light transmittance, decreased the transparency of films, and caused the per cent rate of yellow colour in the films to increase.


edible films, pea proteins, polysaccharides: carboxymethylcellulose (CMC), hydroxypropylmethylcellulose (HPMC), pectins (PEK), chitosan lactate (MCH)