Melting and Storage Characteristics of Soybean Oil Microemulsion Ice Slurry

Ice slurry is a good cold storage medium with a large heat capacity and efficient heat transfer properties. In this study, a microemulsion was prepared with the addition of water, soybean oil as the oil phase, Tween-80 and AEO-3 as surfactants, and amyl alcohol as co-surfactants. The effects of the mass ratio of the oil phase to surfactant, hydrophilic and oleophilic balance of the surfactant (HLB value), and mass ratio of the surfactant to co-surfactant (Km value) on the water solubility of the microemulsion were investigated. A 1∶4 mass ratio of oil phase to surfactant, a 6∶4 mass ratio of Tween-80 to AEO-3 (HLB value of 11.6), and a 2∶1 Km value were the best ratios for the preparation of the microemulsion. An ice slurry was prepared by selecting the microemulsion with 50% water content under the above mass ratios. The influence of ice crystal particle size on the melting process of the ice slurry was studied using ice crystal melting images. The grain size of the ice crystals gradually decreased with increasing melting time. The melting time of the ice crystal particles with large grain size was greater than that of the particles with small grain size. The effects of storage time and ice content on the grain size distribution and average grain size of the ice crystals were analyzed using ice crystal images of the microemulsion ice slurry stored for 1 h and 2 h. The longer the storage time, the larger the grain size of the ice crystals. The number of ice crystals decreased while the ice percentage factor did not change. For the same storage time, the higher the ice content, the faster the growth rate of the ice crystal particle size.