The effect of pectin concentration on viscoelastic and sensory properties of processed cheese

The effect of pectin addition on viscoelastic properties of model processed cheeses with 40% w/w dry matter and 50% w/w fat in dry matter after 42 days of storage at temperature 6 +/- 2 degrees C has been investigated using dynamic oscillation rheometry (plate-plate geometry; frequency range 0.1-50.0 Hz; temperature 20 degrees C). The role of pectin concentration (0.2%, 0.4%, 0.6% and 0.8% w/w) has been studied. Also, the sensory evaluation of samples has been made to assess cheese appearance, rigidity, spreadability and flavour. All samples with the pectin addition were more rigid and less spreadable compared with processed cheeses without pectin. With the increasing concentration of pectin the storage (G') and loss (G') moduli rose at the whole tested frequency range (0.1-50.0 Hz). Growing pectin content resulted in the decrease in loss tangent (the nature of gel was changed to more elastic material). The dependence of processed cheese rigidity on pectin concentration (in range 0-0.8% w/w) was not linear. The appearance and flavour were not worse by pectin addition.