This study demonstrated that inoculation rate and
incubation temperature are significant processing parameters
that affect the physical properties and microstructure
of yogurt gels. As inoculation rate increased
and incubation temperature decreased, the G′ and
σyield values increased, and LTmax, pH at LTmax, B, and
whey separation decreased. During fermentation, the
microstructure changes clearly indicated that there
were extensive rearrangements of the yogurt gel network
incubated at 45.7°C. It was demonstrated that
acidification rate, which affected solubilization of CCP
and thus the pH at LTmax, and rearrangements of casein
particles in gel network, were driving forces responsible
for whey separation. The use of a combination
of an intermediate to high inoculation rate (e.g.,
2%) and low incubation temperature (∼40°C) may provide
yogurt with lower whey separation and less textural
defects.