ANSWER
Stabilizer has the ability to reduce the amount of free water and by immobilizing it within a gel structure which slows the melt down properties. Locust bean gum is especially useful in ice cream as it produces a slow melt down (Clarke, 2012). Whereas, emulsifiers are added to ice cream to control fat destabilization and to increase the resistance to melting (Soad et al., 2014). Mono- and diglycerides of fatty acid (E471) is the most common used emulsifier in ice cream.
Melting time of ice cream is affected by sugar and fat type as well. The formulations added with fructose syrup are generally presented higher melting rate when comparing to the end products made with glucose syrup. Higher melting rate has been observed in the combination of palm fat and fructose syrup (da Silva Junior & Lannes, 2011).
The right choice of emulsifier and stabilizer blends should provide excellent stand-up properties with slower and more uniform meltdown resistance to ice cream.
References
Clarke, C. (2012). The Science of Ice Cream (pp. 158-166). Cambridge: The Royal Society of Chemistry.
da Silva Junior, E., & Lannes, S. (2011). Effect of different sweetener blends and fat types on ice cream properties. Ciência E Tecnologia De Alimentos, 31(1), 217-220. https://doi.org/10.1590/s0101-20612011000100033
Soad, H. T., Mehriz, A. M. & Hanafy, M. A. (2014). Quality characteristics of ice milk prepared with combined stabilizers and emulsifiers blends. International Food Research Journal, 21(4), 1609-1613.