2. Переведите следующие предложения, обращая внимание на герундий и герундиальные обороты.

1. Brewing and baking having a long history is certain. 2. Chocolate being used only as a beverage in the 16^th century is an interesting fact. 3. Pasta products having become an important part of the diet for all the people in the world is evident. 4. Food science proves sugars varying in their composition and properties. 5. We know dough undergoing great changes during its processing. 6. Specialists discovered grain milled by machines being much lower in vitamins and minerals. 7. They insisted on raw material, water and energy being controlled carefully.

Text B₄ MEMBRANE TECHNOLOGY FOR WASTE MINIMIZATION

1. Прочитайте текст и составьте план.

2. Ответьте на следующие вопросы:

1) Что такое мембранная технология?

2) Каковы преимущества данной технологии?

3) Есть ли негативные стороны и в чем они состоят?

4) Назовите основные операции мембранной технологии?

MEMBRANE TECHNOLOGY FOR WASTE MINIMIZATION

Notes:

permeable – проницаемый

retentate – вещество, удерживаемое мембраной, не проходит сквозь ее поры

osmosis – осмос, диффузия растворителя через мембрану и выравнивание концентрации растворов по обе стороны мембраны

Evaporation is a conventional method used for concentration and recovery of material in the food and also in other industries. This is an energy intensive process as the materials have to be heated to evaporate the excess of liquid. As an alternative method, membrane filtration can be used where a selectively permeable¹ membrane is used and driving force is applied in order to separate materials. Depending on the properties of applied membrane (e.g. pore size) the materials either pass through the membrane (this is called permeate), or are rejected (this is called retentate²). If we consider economically the application of membrane technologies, the capital costs are much higher than for evaporation, however, the operating cost are about half and the energy use can be decreased up to 90%.

The other advantage comes from the possibility to prevent the heat sensitive compounds as in membrane technology phase change does not occur. If we consider the process from preservation point of view, the preservation take place without using additives or chemical agents, therefore we are able to get healthier products that are of good quality and during processing fewer by-products are formed. If we think about the equipment, usually their installation does not need big space, they are simple design, flexible and easy to scale-up.

In food industry, application of pervaporation is used for aroma recovery and electrodialysis for demineralization. However, application of pressure driven membrane processes are most common, therefore operation differs in membrane’s pore size and applied pressure, in their ability to retain particles.

In food industry they are used in following operations:

Microfiltration

• juice clarification: removal of suspended solids

• clarification of cheese whey

• defatting and reducing microbial load of milk

• beer and wine clarification

• color removal and particle removal in sugar industry

Ultrafiltration

• juice clarification

• enzymatic depectinization

• gelatin concentration

• starch recovery

• high fructose corn syrup from corn starch (enzymatic membrane reactor)

• solvent recovery and particle removal in oil industry

Nanofiltration

• caustic/acid cleaning recovery solutions

Reverse osmosis³

• fruit juice concentration

• low-alcohol beer

• recovery of soy whey proteins

• downstream process in corn refining

• water recycling

• production of high quality water.

Письменно переведите Text C₄ на русский язык.

Text C₄ VALORIZATION OF FOOD INDUSTRY