Effects of carboxymethyl cellulose and chitosan on the stability of ice cream upon freeze-thaw cycles / Maisarah Shamsudin

Ice cream is a mixture of two immiscible liquids of water and fat, therefore the emulsifier used in preparation of ice cream is very important. This study was conducted to determine the emulsifying effect of carboxymethyl cellulose (CMC) and chitosan in ice cream production upon freeze thaw cycles. Four formulations were developed which are addition of 0.6% commercial emulsifiers smoothex as control, 0.6% chitosan, 0.6% CMC and combination of 0.3% CMC and 0.3% chitosan. The ice cream quality was evaluated in term of viscosity, creaming index, overrun, meltdown, pH value and rheological properties of storage and loss modulus. On overall, results shows that substitution of CMC and chitosan had significant effect toward the quality of ice cream upon freeze thaw cycles. On freshly made ice cream, addition of different emulsifier affects viscosity, pH value, overrun, meltdown, storage modulus and loss modulus but did not affect the creaming index. However, when subjected to freeze thaw cycles, the quality of ice cream was found to be affected by the type of emulsifiers used. Overrun, meltdown and storage modulus showed increasing trend with the increasing number of freeze thaw cycles. Viscosity, creaming index and rheological properties of loss modulus showed decreasing trend with the increasing number of freeze thaw cycles. Only pH value was found not affected by the freeze thaw cycles. Based on the result obtained, the best emulsifier is CMC because it gives the highest viscosity and the most stable creaming value throughout the freeze thaw cycles.