Cooling and Ageing of mix

Cooling of the mix immediately after pasteurization and homogenization is essential.The mix should be cooled to 4.0°C or below. Cooling is usually done using surface coolers, tubular coolers or other type of heat exchangers. The temperatures below 4°C retard the growth of bacteria. Ageing refers to holding the ice cream mix at a low temperature for a certain period of time before freezing. The ageing temperature should not exceed 4.5°C. The ageing time under average commercial conditions may be about 4 hour only. It may be increased depending upon the type of stabilizer in the mix:

Following changes occur in the ice cream mix during ageing:

i) Fat is solidifies

ii) Stabilizer swells and combines with water.

iii) Viscosity increases.

Ageing of ice cream mix offers the following advantages:

i) Improves body and texture of ice cream.

ii) Improves whipping ability of mix.

iii) Increases maximum overrun.

iv) Increases melting resistance of mix.