Abstract: (5031 Views)
Mastitis is one of the most common diseases that can affect composition of milk and hence the products derived from it. In this study oscillatory rheological tests were carried out to determine the effect of somatic cell counts(SCC) on viscoelastic properties of strained yoghurt .Results of strain sweep tests showed that by increasing SCC in samples, structural strength, yield stress, flow point and dependence of elastic modulus (G¢) to strain outside of linear viscoelastic range (LVE) were decreased. Frequency sweep test results revealed that for all samples elastic behaviour dominates the viscous one over the whole range of frequency but by increasing SCC, G* decreased and G¢ became more frequency dependent which means a weaker and also less gel structure, for samples with higher SCC. It was indicated that somatic cell count of milk is a critical factor which affects the quality and yield of strained yoghurt
Received: 2010/07/9 | Accepted: 2011/07/9 | Published: 2012/07/8