No phase separation was observed after centrifugation in any of the samples stored at different conditions up to 21 days. A weak phase separation was, however, recorded on the 21st day and up to the 28th day for preparation of F1 and F3 kept at 40 C. No other phase separation was observed till the end of the experimental period. This was presumably due to the proper homogenization speed during emulsion formulation which might have prevented the breakage of the formulations during t3.1.5. pH value determination
Monitoring the pH value is crucial for determining the emulsions’ stability. In fact, pH changes indicate the occurrence of chemical reactions that can give an idea on the quality of the final product. Furthermore, the most important parts of chemical stability are performances on accelerated testing and kinetics of pH profiles (Issa et al., 2000).
esting (Abdurahman and Rosli, 2006).