Composition, structure, rheological properties, and sensory texture of processed cheese analogues

Processed cheese analogues were made with different fat and moisture in nonfat solids (MNFS) contents and used to study relationships between composition, microscopic structure, rheological properties and sensory texture. Fat contents ranged from 58 to 230 g kg −1 and MNFS from 487.6 to 603.3 g kg −1 . Regressions showed that those rheological parameters measured by uniaxial compression at large deformations and moderately high rates were best explained by linear combinations of MNFS, protein and fat. The moisture in the protein network acted as a plasticiser lowering the rheological parameters. Fat alone had little direct effect on the rheological characteristics under these conditions but at small deformations and low deformation rates it formed elastic inclusions that contributed to the properties. Examination of fracture surfaces in the SEM suggested that, during fracture, fat was squeezed out and acted as a lubricant. Maximum stress and work to maximum stress measured at moderately high deformation rates related best to the sensory results and described fracture of the cheeses. From the regressions, for 95% confidence limits, sensory analysis could theoretically measure changes within the range of composition tested of <0.1% in MNFS or fat. Of the rheological parameters only work to maximum stress was as sensitive. However, interaction between these compositional factors reduced the sensitivity in practice.