Effect of tragacanth gum and exopolysaccharide producing starter on quality, textural and microstructural properties of cheddar cheese

Tragacanth gum and EPSs have properties that they can be fat replacers in cheese. The effect of tragacanth gum and EPS producing starter on physicochemical, textural and microstructure properties of low-fat cheddar cheese was investigated during ripening. Cheddar cheese was produced in 5 treatments, including: low fat and full fat control, containing 0.06 % tragacanth gum, containing EPS producing starter and containing combination of 0.06 % tragacanth gum and EPS producing starter. Samples were vacuum packed and stored for 6 months in 6 ± 1°C. The results of ANOVA showed that with addition of tragacanth gum, dry matter and fat in dry matter of cheeses decreased and salt and cheese production yield increased in comparison to full- fat control sample (P0.05). In images of samples containing tragacanth gum obtained by scanning electron microscopy, a protein matrix with many holes was observed while the samples containing EPS producing starter, had more homogeneous structure and samples containing both fat replacers, were between two conditions. The results of sensory evaluation also showed that adding of tragacanth gum and EPS producing starter had no significant effect on sensory factors (P>0.05.(.The results of this research showed that tragacanth gum and EPS producing starter can be used as fat replacers with desirable textural properties in cheddar cheese production.