The aim of this study was to investigate the structure and the film-forming capacity of the polysaccharide kefiran (extracted from kefir grains) using FTIR spectroscopy. Different forms of the polysaccharide (kefiran solution, frozen kefiran and kefiran pellet) were subjected to infrared measurements. Solutions of kefiran with different concentrations of glycerol (5, 7.5, 10 or 15% w/w) were prepared. The film-forming solutions of kefiran and the characteristics of the resulted biofilms were tested. The biofilm obtained from kefiran solution with 7.5% w/w glycerol had the best characteristics (transparency and elasticity).
FTIR spectroscopy results showed that the structural integrity of kefiran was maintained in biofilms, which highlights the relationship between chemical composition and future applications of the polysaccharide.