Pasteurization of Ice cream mix

All liquid ingredients (milk; cream etc.) are placed in stainless steel tank provided with a stirrer. The heating of liquid ingredients is started with stirring. The mix ingredients are mixed thoroughly. The dry ingredients (skim-milk powder, sugar,stabilizer etc.) are then added slowly with proper mixing. The heating of the mixture continued up to 49-50°C while mixing the ingredients. If gelatin is used as stabilizer,it is added to the liquid ingredients before heating started. If sodium alginate is used as stabilizer, it should be added when the temperature of mix reaches 65°C or above. It should never be added to cold mix. Proper pasteurization of all mixes is compulsory because this process gives the following advantages:

a) Destroys all pathogenic or disease producing bacteria, thereby safe guarding the health of the consumer:

b) Brings the ingredients of the mix in to solution and aids in blending.

c) Improves flavour.

d) Improves keeping quality.

e) Produces a more uniform product.

Proper pasteurization consists of rapidly heating the mix to a definite temperature,holding it at that temperature for a definite period of time and then rapidly cooling to below 5°C.

The recommended pasteurization temperature-time combination for ice cream mix are as follows:

a) Batch method = 68.5°C for not less than 30 minutes

b) High temperature -Short time (HTST) Method = 80.0°C for not less than 20 seconds

The present trend is towards higher temperature processes like Ultra high temperature for few seconds.