Lipid and protein structure analysis of frankfurters formulated with olive oil-in-water emulsion as animal fat replacer

Abstract

► Lipid and protein structure of frankfurter with oil-in-water emulsion were studied. ► FT-IR was used to determine structural features of lipid and protein. ► Emulsions like pork backfat replacer were stabilized with soy protein. ► Structural characteristics could be associated with textural properties. Lipid and protein structural characteristics of frankfurter formulated with olive oil-in-water emulsion stabilized with soy protein isolate (SPI) as pork backfat replacer were investigated using Fourier transform infrared spectroscopy (FT-IR). Proximate composition and textural properties were also evaluated. Different frankfurters were reformulated: F/PF with pork backfat, F/SPI with oil-in-water emulsion stabilized with SPI and F/SPI + SC + MTG with emulsion stabilized with a combination of SPI, sodium caseinate (SC) and microbial transglutaminase (MTG). Replacement of pork backfat with these emulsions produced an increase ( P < 0.05) of hardness, springiness, cohesiveness and chewiness but a reduction ( P < 0.05) of adhesiveness. F/SPI and F/SPI + SC + MTG frankfurters showed the lowest ( P < 0.05) half-bandwidth in the 2922 cm −1 band, which could be related to lipid chains were more ordered than in F/PF. Modifications in the amide I band profile revealed a higher concentration of aggregated intermolecular β-sheets in F/SPI + SC + MTG samples. Lipid and protein structural characteristics could be associated with specific textural properties of healthier frankfurters.