The use of spinning disc reactor for processing ice cream base - effect of ageing in making model ice cream

Spinning disc reactor (SDR) technology was tested to produce an ice cream base, which was subsequently used to make model ice cream. The ice cream base containing butterfat, lecithin, xanthan gum, sugar, skimmed milk and double cream was passed over the SDR disc spinning at 2900 rpm, heated at 80 degrees C and at a flow rate 6 mL s(-1). The physical properties of the SDR-processed ice cream base such as particle size and viscosity measurments, and of model ice cream including overrun, meltdown rate and sensory perception were investigated. The SDR-processed ice cream base exhibits narrow particle-size distribution (average particle d(32) = 1.65 mu m, d(43) = 2.98 mu m) and the viscosity was found to be similar at zero and 18 h ageing, whilst the model ice cream requires zero-hour ageing and has a high overrun value (similar to 85%) and slow meltdown rate as compared with a commercial sample. The results reveal that the SDR is capable of producing a highly stable ice cream base that requires significantly less ageing than the 18 h typically associated with the traditional process of making ice cream. The SDR process provides intense mixing of ingredients which facilitates the hydration of milk proteins and stabilisers.