In general following steps are followed in the process of making ice cream.
1. Blend Ingredients.
2. Pasteurisation of mix.
4. Ageing of mix.
5. Adding flavours & Colours.
The first Step in making ice cream is to mix all the ingredients like milk, solid non fats, stabilizers, emulsifiers, sugar and dairy fat.
In general ice cream mix consists of 11.3% of SNF, 16-18% Sugar, 0.45% stabilizers and emulsifiers, 8-11% dairy fat.
After making the mix, the mix is pasteurized at 79.4 C For about 30 sec.Pasteurization is done to eliminate pathogens in the mix and help to increase the shelf life of the final product.
After pasteurization the mix is homogenised at 2500-3000 PSI this is done to decrease the fat globule size. which in turn gives nice and smoother texture to the ice cream . the homogenised mix which is about 78 C will be brought to 4 C by passing it through chillier / plate heat exchanger. The mix is then collected in aging vat and aged for about 6 hrs/over night at 4 C, this increase / improves the whipping properties of the mix.
liquid colours & flavours are added before freezing the mix into ice cream In general batch freezers / continuous ice cream freezers are used to freeze mix into ice cream. The output product comes at -5 C from the freezer.
Then ice cream is cooled as quickly as possible to -16 C by using harding tunnels. Rapid cooling will promote quick freezing of water and create small ice cream crystals. which in turn gives smoother texture to ice cream.