butter oil.pptx

Food

1. Anhydrous Milk Fat (AMF) and Butteroil

2. Anhydrous milk fat and butteroil are products consisting of more or less pure milk fat. Although they are modern industrial products, they have ancient traditional roots in some cultures. Ghee, a milk fat product with more protein and a more pronounced flavor than AMF

3. Anhydrous Milk Fat must contain at least 99.8 % milk fat and be made from fresh cream or butter. No additives are allowed, e.g. for neutralisation of free fatty acids. • Anhydrous Butteroil must contain at least 99,8 % milk fat, but can be made from cream or butter of different ages. Use of alkali to neutralise free fatty acids is permitted. • Butteroil must contain 99,3 % milk fat. Raw material and processing specifications are the same as for Anhydrous Butteroil.

4. Principles of production Production of AMF principally takes place according to two methods: continuous flow direct from cream and from reworked butter

5. Manufacture of AMF from cream Pasteurised or non- pasteurised cream of 35 – 40 % fat content enters the AMF plant via the balance tank (1) Routed via the plate heat exchanger (2) for temperature adjustment or pasteurisation Centrifuge (4) for pre-concentration of the fat to about 75 %.

6. The temperature at preconcentration and downstream to the plate heat exchanger (11) is maintained at approx. 60 °C. The “light” phase is collected in a buffer tank (6) to await further processing while the “heavy“ phase, typically called buttermilk , can be passed through a separator (5) for recovery of fat which will then be mixed with incoming cream (3).

7. The skimmed buttermilk goes back to the plate heat exchanger (2) for heat recovery and then to a storage tank. After intermediate storage in tank (6), the cream concentrate is fed to a homogeniser (7) for phase inversion (disruption of the fat globules to release the fat), after which it is passed through the final concentrator (9).

8. concentrator the product is separated into a light phase with 99,5 % fat and a heavy phase, with a substantial amount of fat, which is returned to the process via balance tank (3) As the homogeniser operates at a slightly higher capacity than the final concentrator, the surplus product not caught by the concentrator is recirculated to the buffer tank (6). Part of the mechanical energy used in the homogenisation process is converted into heat; to avoid disturbing the temperature cycle of the plant, this surplus heat is removed in the cooler (8).

9. Finally, the oil consisting of some 99,5 % fat is pre-heated to 95 – 98 °C in a plate heat exchanger (11) and routed into a vacuum chamber (12) To obtain a moisture content not exceeding 0,1 %, after which the oil is cooled(11) to approx. 40 °C, the typical packing temperature

10. AMF refining Polishing Neutralisation Fractionation Decholesterolisation

11. Polishing Polishing involves washing of the oil with water to obtain a clear, shiny (bright) product. 20 – 30 % water is added to the oil coming from the final concentrator The water temperature should be the same as the oil temperature. After a short hold, the water is separated out again, taking water-soluble substances (mainly protein) with it

12. Neutralisation Neutralisation is performed to reduce the level of free fatty acids (FFA)present in the oil High levels of FFA give rise to off- flavours in the oil Alkali ( NaOH ) at a concentration of 8 – 10 % is added to oil in an amount corresponding to the level of FFA. After a hold of around 10 seconds, water is added in the same proportion as for polishing, the saponified FFA is separated out together with the water phase.

13. Fractionation Fractionation is a process where the oil is separated into high-melting and low-melting fats. These fractions have different properties and can be used in various products The AMF, often polished to obtain the highest possible degree of purity in the “raw oil”, melted and then cooled slowly to a calculated temperature the specified fraction crystallises out while fractions with lower melting points remain liquid.

14. The crystals are harvested with special filters. The filtrate is then cooled to a lower temperature at which other fractions crystallise and are harvested

15. Decholesterolisation Decholesterolisation is a process in which cholesterol is removed from the AMF. A frequently used method is to mix the oil with a modified starch, betacyclo dextrine (BCD). The BCD molecule surrounds the cholesterol and forms a precipitate, which can be separated out by centrifugation.

16. Packaging AMF is filled in containers an inert gas, nitrogen (N2), is first injected in the container. the N2 gas is heavier than air, it sinks to the bottom When filling the AMF –which is heavier than N 2 – the AMF will sit underneath and the N2 gas will create an “air-tight lid”, preventing the AMF from air-induced oxidation.