Thermal Analysis of Lipid Crystallization and Water Ice on Coconut Milk Emulsions: Effect of NaCl Concentrations

Gingkaew Pairoh, Tatsawan Tipvarakarnkoon
2013 Journal of Medical and Bioengineering  
The aim of this study was to investigate the effect of NaCl concentrations at low temperature (50 to -80C) on lipid crystallization and freezing water of coconut milk emulsions. Phase change behavior of coconut milk emulsions has been evaluated using differential scanning calorimetry at heating/cooling rate of 2C/min. Unhomogenized coconut milks (34% fat content) showed an overlapping peak of fat crystals with an onset at 8C and a large exothermic peak of freezing water at -20C during
more » ... g. Reheating sample leads to water ice melt at 0C and subsequently a melting of coconut fat with an endset of 25C. Commercial coconut milks (18 -20% fat content) exhibited more than three peaks of crystallization due to a variety of oil droplet sizes in emulsions. To study the effect of salt, NaCl (0 -4%) were then added to coconut milk (20% fat content) containing 5%w/w acacia gum. Homogenized coconut milk emulsions showed lower crystallization and melting temperatures of water ice in the presence of NaCl. However, it does not affect phase change of fat crystals. Freezing depression could be seen only on aqueous phase of its emulsion. 
doi:10.12720/jomb.2.3.191-195 fatcat:wxfhgxkv5nhc7fvbbabq5mwgcq