Optimization of the stabilizers and cow milk levels for the production of camel milk-based yogurt using response surface methodology

Abstract

The production of yoghurt from camel milk (CML) is limited due to weak gel formation. As a trial to produce CML-set-type yoghurt, sixteen treatments were prepared from CML, cow milk, and stabilizers (gelatin and gum-Arabic; 1:1) using a D-optimal design. A desirable hardness of set-type yoghurt was obtained from CML (56%), cow milk (42%), and stabilizers (2%). Another study was designed to choose the best combination of stabilizers (1, 1.5 or 2% of gelatin in combination with 1% of gum-Arabic). The increased levels of gelatin resulted in a significant increase (p < 0.05) in the viscosity and consistency index of yoghurt milk, an increase (p < 0.05) in yoghurt hardness and viscosity, and a reduction in syneresis (p < 0.05). In conclusion, an acceptable set-type yoghurt can be produced by using a combination of CML and cow milk (1.3:1) and a stabilizers' mixture of gelatin (1 or 1.5%) and gum-Arabic (1%).