Английский язык. Профессиональное общение специалистов в сфере технологии продовольственных продуктов и потребительских товаров. Учебное пособие

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2.Oil seeds are passed over magnets …

a)to crush the material;

b)to produce a clear oil;

c)to remove any trace metal.

3.The oil is refined …

a)to attain the maximum yield;

b)to remove color, odor, bitterness;

c)to inactivate trace metals.

18. Ответьте на следующие вопросы.

1.Is the method of cold pressing suitable for all kinds of oils?

2.What are the main steps in oil manufacture?

3.What machine crushes the materials to the proper consistency?

4.What unit is used to meet the demands of the US soybean oil industry?

5.What does the oil refining consist of?

6.What is the final step in oil manufacture?

19. Прочитайте заголовок текста В и переведите его на русский язык. Просмотрите текст и определите вопросы, которые, как вы думаете, будут обсуждаться в этом тексте.

20. Найдите в тексте В предложения, описывающие различные методы обработки животных жиров.

Слова для понимания текста В.

bone fats - костный жир

dry rendering - сухой способ вытопки (жира) wet rendering - мокрый способ вытопки

impulse rendering - импульсный способ вытопки

cold rendering process - способ обезжиривания в холодной воде screw extruder - шнековый экструдер

to deteriorate - портиться, разрушаться direct heating - прямой обогрев

steam heater jacket - паровая рубашка (устройство для нагрева)

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to rupture - разрывать(ся) boiler - бойлер, паровой котел

Text B

Processing of animal fats

Animal fats especially from land animals are usually obtained by the wet or dry rendering process. The extraction process with solvent and the pressing procedure are only used for the production of bone fats and fish oils. Special centrifuge procedures are used to obtain the fat from milk.

When obtaining fats from land animals, it is necessary to process the fatty tissues quickly as they deteriorate rapidly. Fats are obtained either by so-called dry rendering, in which the fat is melted out in boilers with direct heating, or more gently in boilers with a hot water or steam heater jacket. In wet rendering the fat is melted out by direct steam (fresh steam) or by hot water in open or in closed steam boilers.

In fish oil production whole or chopped fish are boiled to a thick mass and then pressed in a screw extruder. The fluid from the pressing is separated by centrifugal action into oil.

Liver oils are obtained after careful preparation of the raw materials by rendering (50-90 ºC) or careful boiling and the oil and water phase separated in special centrifuges.

The Chayen cold rendering process has been developed in England. Here cold water is used instead of heat and solvents to remove the fat from the raw material (bones, oil seeds, fish liver, herrings, etc.). The comminuted raw material is led continuously, with large amounts of water, into a kettle where mechanical vibrators send strong high frequency impulses through the water. The effect is similar to that of high pressure waves. The cell walls are ruptured and the contents are washed out immediately.

The expelled fat collects on the surface of the water and is separated by centrifuge. This «impulse rendering» is very quick and yields high quality fats. Bones (and also oil seeds) can be defatted up to 98,5 %.

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УПРАЖНЕНИЯ

21. Переведите письменно на английский язык следующие предложения.

1.Животные жиры, особенно от наземных животных, обычно получают способом сухой или мокрой вытопки жира.

2.При получении жира от наземных животных необходимо быстро проводить обработку жировых тканей.

3.При производстве масла из рыбы целая или нарезанная рыба варится до густой массы и затем прессуется в шнековом экструдере.

4.Сырье непрерывно поступает с большим количеством воды в чан, в котором механические вибраторы через воду посылают импульсы высокой частоты.

5.Импульсный способ вытопки жира является очень быстрым и производит высококачественные жиры.

22. Закончите следующие предложения, выбрав подходящий вариант из частей предложения, указанных буквами ниже.

1.The extraction process with solvent and the pressing procedure are only used …

2.The fluid from the pressing is separated by …

3.The Chayen cold rendering process …

4.The effect is similar to that of …

5.In wet rendering the fat is melted out by direct steam or by …

6.The cell walls are ruptured and the contents …

a)hot water in open or in closed steam boilers

b)has been developed in England

c)high pressure waves

d)centrifugal action into oil

e)for the production of bone fats and fish oils

f)are washed out immediately

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23. Укажите, какие из данных утверждений неправильны или не соответствуют содержанию текста. Подтвердите свои ответы фактами из текста.

1.In the Chayen cold rendering process heat and solvent are used to remove fat from the raw material.

2.The expelled fat collects on the bottom of the kettle and is separated by centrifuge.

3.Special centrifuge procedures are used to obtain the fat from milk.

4.Animal fats especially from land animals are usually obtained by centrifuge.

5.The impulse rendering is very quick and yields high quality fats.

24. Обобщите полученную информацию, заполнив следующую таблицу

25. Прочитайте три отрывка. Озаглавьте каждый отрывок и скажите, какие из них дополняют информацию текстов А и В.

1. The crude fats and oils produced by rendering, expression, or solvent extraction, contain variable amounts of nonglyceride impurities. In the case of high-grade animal fats and certain vegetable oils, such as coconut and palm kernel oils, these impurities consist principally of free fatty acids. There are significant amounts of other substances, however, in most vegetable oils as well as in animal fats, which have been rendered from low-grade materials.

Not all of the impurities of crude oils are undesirable. The sterols are colorless and heat-stable, and for all practical purposes, inert: hence they pass unnoticed unless present in unusually large amounts. Tocopherols and certain related compounds perform the important function of protecting the oil from oxidation. For this rea-

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son they may be classed as highly desirable constituents of most oils and fat production.

Sterol and certain constituents which are present in traces only, including tocopherols, hydrocarbons, chlorophyll, carotenoid pigments and cationic or other odoriferous substances are relatively little affected by ordinary refining treatment, and hence are found even in well-refined oils. However, free fatty acids, phosphates, carbohydrates, nitrogenous or pertinacious compounds and resinous and mucilaginous substances are ordinarily removed by refining.

2. The separation of oils and fats from oil-bearing animal and vegetable materials constitutes a distinct and specialized branch of fat technology. The widely differing characteristics of different fatty materials have given rise to such diverse extraction processes as rendering, pressing and solvent extraction.

Fatty animal tissues consist largely of fat and water, which may be separated from the solid portions of the tissue and from each other with relative case, by one of rendering processes. The extraction of vegetable oil is more difficult matter. Vegetable materials, and in particular some of the oil-seeds, contain a large proportion of solid material associated with the oil careful reduction of the material, followed by heat treatment and the application of heavy pressure, is required to obtain an efficient separation of the oil from the solids.

Even after the most efficient pressing, an oil cake will retain an appreciable amount of absorbed oil; the latter will usually amount to 4-7 % of the weight of the case.

There are a number of more or less critical operations in oil milling, which are maxillary to the actual expression or extraction. Wherever possible it is desirable to decorticate oil seeds before the oil is removed in order both to increase the capacity of the extraction equipment and to avoid lose of oil through absorption by the hulls. The seeds must then be ground, or otherwise reduced to fine particles. After they are reduced, they must be given heat treatment to make the walls of the oil sells permeable to the oil and to render the oil free following. In addition, oil milling or extraction presents problems in the handling and storage of the oil-bearing materials since these are prone to deteriorate, through oxidation, or bacterial or enzyme action.

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3. One of the most noticeable characteristics of oils and fats is their oiliness or ability to form lubricant films. In this respect, they are quite similar to long chain hydrocarbons. Although the fatty oils have been largely replaced by petroleum products as lubricants for machinery, there are a number of other technical applications in which their primary function is that of lubrication and even in some products their lubrication action is important.

Oils owe their relatively high viscosities to their long chain structure of their glyceride molecules; hence the viscosity of blown, heatbodied or other polymerized oils is much greater, than that of normal oils. In general, the viscosity of oils decreases slightly with increase in their degree of unsaturation. Oils containing fatty acids of low molecular weight are slightly less viscous than oils of an equivalent degree of unsaturation containing only high molecular weigh acids. Rapeseed and other erucic acid oils are a little more viscous than equally unsaturated oils composed of c16 and c 18 acids. Castor oil is in a class by itself with respect to viscosity, being very much more viscous than other oils.

Since viscosity is to some degree dependent upon unsaturation the viscosity of oil is increased somewhat by hydrogenation. Fatty acids change less in viscosity with change in temperature than do mineral oils.

26. Ответьте на вопросы отрывка 1.

1.What do the crude fats and oils contain?

2.Are all of the impurities of crude oils undesirable?

3.What constituents are ordinarily removed by refining?

27.Составьте 5-6 вопросов к отрывку 2 и задайте их своему товарищу. Ответьте на его вопросы.

28.Переведите отрывок 3 на русский язык письменно с помощью словаря за 30 минут.

29.Прочитайте текст и переведите его на английский язык. Придумайте заголовок к тексту.

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tains approximately 45-47 per cent oil, 25 per cent hulls and 14 per cent protein. The rest is usually moisture.

Sunflower seed provides high quality salad and cooking oils, as well as other final products (margarine with polyunsaturated fatty acids, mayonnaise, salad dressing and the like). It is very stable and can endure long periods of storage and transport in a wide range of climatic conditions, compared to most other liquid oils such as soybean and rapeseed oils. It is also used for deep frying with good results. Sunflower proteins are used for cattle feed and as supplements to human foods.

A certain amount of sunflower seed hulls (6 to 8 per cent) remains in the meal and is used as animal feed. Better use of hulls implies the application of microbiological and chemical processes in the production of feeds, waste products and single-cell proteins. Some research work is already under way.

The hulls are used widely as a construction material (thermoisolation plates) as well as a medium-calorie fuel. An industrial plant with a processing capacity of 600 t/d of sunflower seeds provides about 100 t/d of sunflower seed hulls through decortications, consuming about 6,5 tons of steam per hour. The hulls thus obtained can produce in a suitable vertical boiler 25 tons of steam enough to supply the same factory.

УПРАЖНЕНИЯ

31. Найдите в тексте С ответы на следующие вопросы.

1. What can be taken from ripe sunflower seeds?

2. Where and how effectively are sunflower seeds used?

3. In what direction is research work of using sunflower seed hulls going?

4. What are other non-edible types of sunflower seeds usage?

32. Прочитайте первые предложения текста С и соотнесите их с содержанием заголовка. Скажите, как вы представляете себе главную мысль текста.

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33. Выделите в тексте вводную, основную и заключительную части. В каждой части текста найдите предложение, передающее его основную мысль. Озаглавьте каждую часть текста.

34. Кратко передайте содержание текста С, используя следующие фразы-клише.

1.The subject of the text is …

2.The text deals with …

3.It is pointed out that …

4.It should be stressed that …

5.It is specially mentioned that …

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РАЗГОВОРНАЯ ТЕМА «MY FIELD»

1. Прослушайте и повторите следующие слова.

мechanic, technology, automatically, economy, qualified, industry, speciality, production, calory, solvent, compound, necessary, essential, impossible, important

2. Прослушайте и повторите следующие служебные слова.

тhere, those, their, now, upon, where, which, with

3. Прочитайте и запомните слова по теме.

qualified specialist - квалифицированный специалист necessary - необходимо

foodstuff - пищевой продукт to possess - обладать, владеть excellent - отличный

solvent - растворитель dangerous - опасный

protective layer - защитный слой derived - производный

essential - существенный brain - мозг

living organism - живой организм application - применение

soap manufacture - производство мыла decomposition - расщепление

to require - требовать

to witness - быть свидетелем

calorie density - степень калорийности

fat-soluble vitamins - жирорастворимые витамины

4. Прочитайте и переведите текст «My field is the Technology of Fats and Oils Production». Используйте его для беседы по теме «Моя специальность».