Eduqas GCSE Food Preparation and Nutrition: Student Book

MILK, CHEESE AND YOGHURT 245 SECTION 3 Ultra heat treated milk (UHT) UHT milk is heated to a temperature of at least 135ºC for one second in order to kill off any harmful bacteria it may contain. The milk is then packaged into sterile containers which can be stored, unopened, at room temperature for up to six months. Once opened, UHT milk must be treated the same as fresh milk. Processed milks Evaporated milk 50% of the water is evaporated from the milk which is then homogenised to prevent the fat from separating out. The evaporated milk is poured into cans, which are then sealed. The cans are heated for 10 minutes at a high temperature. Processing gives evaporated milk its slight caramel flavour and richer colour. The shelf life of evaporated milk is generally 12 months. Once opened, it must be kept refrigerated at 5 ºC. Condensed milk To obtain condensed milk, fresh milk is heated to a temperature of 110–115ºC for one to two minutes, homogenised, and sweetened with sugar. It is then evaporated at a temperature of 55–60ºC. The milk is then cooled rapidly to 30ºC and canned. Condensed milk is three times more concentrated than fresh milk. It is very sweet and has a thick, syrupy consistency. It is commonly used in the confectionary industry to make toffee, caramel and fudge. It is often used in very hot countries to replace fresh milk or where there is no access to a refrigerator. Dried milk Dried milk is produced by evaporating the water in milk. The milk is homogenised, heat treated and pre-concentrated before drying. The concentrated milk is sprayed into a chamber of circulating hot air causing the droplets of milk to lose their water content and fall to the floor of the chamber as fine, dried milk powder. Dried milk powder can be stored at an ambient temperature for up to one year. Once it is reconstituted with water it can be used just like fresh milk. Dried skimmed milk powder mixes very easily with water, whereas dried whole milk powder tends to form small lumps when reconstituting. Reconstituted milk must be treated and stored like fresh milk. Comparing the fat contents in processed milks  EVAPORATED MILK 4–10% FAT CONTENT  CONDENSED MILK 10% + FAT CONTENT  DRIED MILK 0–3% FAT CONTENT Evaporated milk Condensed milk Dried milk