Butter Production
There are two similar processes to make butter; the Fritz process and the Ammix process. They involve the exact same steps but are ordered differently.
Currently, the majority of New Zealand’s total butter manufacture uses the Fritz process. However, there is a gradual shift to the Ammix process. The Ammix process has considerable advantages over the Fritz process (New Zealand Dairy Research Institute, 1998).
Advantages of Ammix process:
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Crystallisation stage taking a matter of minutes as opposed to hours
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The ability to make spreadable butter, tropical butter, low fat spreads and many more useful products using the Scraped-surface heat exchanger (SSHE) technology.
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More flexible compared to Fritz in terms of the ingredients being able to be added individually.
In the industry the current process is the Fritz process as shown in Figure 1.
Figure 1 - Diagram of the Fritz Process
Concentration: Concentrates milk from 4% fat to cream of 40% via the centrifugal cream separator. It is then vacuum pasteurised and steam stripped to reduce some of the pastoral flavours.
Crystallisation: Cream is left in huge storage tanks overnight to cool and crystallise the milkfat. The ideal yield is 40-45% of milk fat to crystallise.
Phase Inversion: Churning the cream with air separates the fat from buttermilk. Buttermilk is then drained off until a stable water-in-fat emulsion is reached.
Working of the butter: This gives the butter the uniform structure which we know it. Two rotating augers and plates kneads the butter and excess water is squeezed out. Salt is optional, and can be added in this stage (New Zealand Dairy Research Institute, 1998).
Packaging: Automatic packing machines are used to ensure prolonged shelf life.
Fun Fact: The waxed paper and aluminium foil (used for packaging) act as opaque and air tight packaging materials in order to protect the butter from reduction in quality (Gdv, 2011).
By Zoe Foreman
