Pasteurization in baby food
For a general overview of infant formula production, please see Evaporation
Figure: Infant formula baby food process flow sheet
The ever increasing focus on a hygienic production of an infant formula has made a high-heat heat treatment of the concentrate necessary.
The heat treatment may be either a mild pasteurisation, depending on product type and stage in the manufacturing process. Pasteurisation is a process of heating the formula to a temperature that will kill any living microbes without changing the chemistry or flavour. Selecting the right heat treatment depends on a careful evaluation of the balance between high bacteriological quality and low destruction of valuable nutrients.
Several pasteurisation methods are commercially available. One common method warms the formula by sending it through a tube adjacent to heat plate heat exchanger. Thus the formula is heated indirectly. Another method heats formula directly and then uses the heated liquid to preheat the rest of the incoming formula. The preheated formula is further heated with steam or hot water to the pasteurisation temperature. After pasteurisation is complete, the batch may be processed further by homogenisation.
Depending on product composition, this heat treatment is done either before the evaporation stage or after.
Figure: Mixing tanks-pasteuriser-homogeniser Source: GEA Niro
Direct steam injection up to 100-140°C (212-284°F) for fractions of seconds, followed by a flash cooling to 80°C (176°F).
Alternatively 85-94°C (185-201° F) held for about 30 seconds