MANUFACTURE OF ICE CREAM
Ice cream products are prepared for consumption in the frozen state, but many other dairy products are frozen as a means of preservation. Frozen milk, frozen cream, frozen concentrated milk, and frozen concentrated skim milk are especially prepared for preservation by freezing and holding for future wholesale and retail use. Frozen cream and concentrated milks act as an industry balance wheel, since they are held from seasons of high production and used in seasons of scarcity.
Ice cream is a complex system in which the stable mixed emulsion of four phase system, fat-water-ice-air, must be balanced and protected from breaking or separating. The manufacture of ice cream starts with making the mix. This is composed of a combination of suitable dairy products such as cream, milk, or skim milk either concentrated or dry. At least two mixing tanks and three aging tanks are needed to feed mix continuously to the freezer. The complete mix must be homogenized, pasteurized, and aged for at least four hours to condition it for freezing. The ice cream is extruded from the freezer by means of special extruder into packages that are packed by packaging device and then are conveyed on the belt conveyor to the hardening and storage rooms. The mix is compounded and frozen in such a way that the final product is smooth, homogeneous, and free of coarse ice crystals. Emulsifiers and stabilizers are used to finely distribute the milk fat, the ice crystals, and the air bubbles of the frozen product. Sugar in the mix is essential not only to give sweetness but also to lower the freezing point.
Incorporation of air in a mix during freezing (overrun) can double the volume. Hand freezers beat air into the mix as the water froze, but commercial freezers meter the air in under controlled conditions. The air must be incorporated and distributed as very fine bubbles.
Freezing is done with great rapidity and under severe agitation. The common drawing temperature for batch freezers is 24˚F (-5˚C), when about 38% of the water in the mix is frozen. In the newer continuous freezers 54% of the water is frozen and the ice cream is drawn at 21˚F (-6˚ C).
Exercise 3. Match the terms and their translations:
| 1. a refrigerating stationary chamber | a. оросительный водоохладитель |
| 2. a packaging automatic device | b. гомогенизатор |
| 3. a freezer | c. сыродельная ванна |
| 4. a quick freezing chamber | d. резервуар для созревания |
| 5. a packaging and hardening line | e. морозильная стационарная камера |
| 6. a pasteurizer | f. упаковочный аппарат |
| 7. a cheese-making bath | g. фризер |
| 8. a homogenizer | h.дозатор |
| 9. a water-drip cooler | i. линия фасования и закаливания |
| 10. a storage tank | j. пастеризатор |
| 11. an ageing tank | k. скороморозильная камера |
| 12. a feeding machine | l. резервуар для хранения |
Exercise 4. Answer the questions to the text:
1. Why is the Russian dairy industry developing so quickly?
2. How can all dairy products be classified?
3. What requirements should the equipment for dairy industry comply with?
4. What factors are obstructing in the development of the milk processing sector?
5. Why is there an urgent need for modern equipment and new technologies in the dairy industry?
6. What leading companies of the Russian dairy industry do you know?
7. What is the role of the packaging equipment for the dairy industry?
Exercise 4. Look through the text again and make a list of the equipment necessary for ice cream production.
Exercise 5. Speak about the technological line on ice cream production.
TEXT 3
Exercise 1. Read and translate the text with the help of a dictionary:
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