Cheese rheology has been an ever expanding field in recent times. It is concerned primarily with the deformation and flow of cheese under certain conditions. It is essential that we understand the rheology of cheese for ample reasons. It helps understand better the structure of cheese as well as to determine quantitievely the attributes demanded by the consumers.
Fundamental tests have become more significant than empirical and imitation tests for the study of the rheological behavior of cheese. Small-Amplitude Oscillatory shear is a fundamental test that provides a better understading of the structure of various kinds of cheese. This paper will explain the basics of the Small-Amplitude Oscillatory Shear test (SAOS) as well as the various tests’ results on four of the most popular cheeses: Cheddar, Gouda, Feta and Mozzarella.
Small-Amplitude Oscillatory Shear (SAOS) experiments are used to detect and study the viscoelastic properties of complex materials, including cheese, which undeniably exhibits viscoelastic behavior.
SAOS is one branch of the dynamic mechanical analysis (DMA), a material characterization technique used to measure the dynamic mechanical properties of materials through a sinusoidal oscillating stress or strain.
SAOS is used because it provides vital information about the viscoelastic properties of the material, while not damaging the structure. This is due to small strains(or stresses) being used, making it nondestructive. Moreover, tests are performed rather easily and are precise within a reasonable range of frequencies.
Parallel plate torsional rheometer is the equipment usually used in SAOS experiments for semi-solid foods, such as Mozzarella and cream cheese. A specimen disk is put between two parallel plates and is subjected to sinusoidal oscillation. This is done in the viscoelastic region of the cheese.
SAOS material functions
The first step in deriving the SAOS material functions is...