Wastes/by-products

Notes:

valorization – валоризация, мероприятия по обработке отходов с целью их последующего использования (с экономической выгодой)

Food industry usually generates large amounts of solid wastes and by-products which have to be managed or used whenever possible.

Valorization¹ techniques include different separation technologies, such as mechanical and diffusional separation technologies, as well chemical and biochemical modifications.

Mechanical separation methods

From the mechanical separations, the mechanical extraction or pressing is used often for solid-liquid phase separation method. Fat and oil in different oil seeds are separated by pressing, and it can be used for fruit juice extraction.

Diffusional separation methods

Diffusional separation methods, such as distillation, different forms of

extraction, adsorption, ion exchange, evaporation, crystallization, drying and

membrane separation are widely used in different areas of food industry for by-product valorization.

Chemical separation methods

From chemical modifications, hydrolysis, i.e. breaking up of a chemical compound influenced by water. The addition of strong acids, bases or steam will be often applied if ordinary water has no effect. Some examples for use of hydrolysis includes the conversion of starch into sugars in a presence of strong acid catalyst, the conversion of animal fats or vegetable oils to glycerol and fatty acids by reaction with steam, or just the conversion of proteins, fats, oils or carbohydrates by enzymes.

Biochemical methods

Biochemical modification for food by-product valorization includes pasteurization, fermentation, biogas production and enzymatic treatment. Pasteurization, such as HTST (high temperature short time) and LTLT (low temperature long time) pasteurization in usually applied in dairy industry for utilization of by-products.

The product of fermentation processes varies greatly on the particular microorganisms involved, e. g. yeast and fungi result in ethanol production from glucose.

Enzymatic treatment is the other application field of biochemical methods. Enzyme can be used for the degradation of food waste consisting of proteins, lipids and carbohydrates. Enzymes are also used to degrade plant cell walls and help e.g. the extraction of oils or other valuable compounds from seeds, skins and peels.

Unit 5. Extrusion in food production

Grammar «–ing FORMS »

Text A₅ EXTRUDING IN FOOD PROCESSING

Active Vocabulary

1. extrusion – экструзия, выдавливание

to extrude – выдавливать, формовать выпрессовыванием через отверстия

extruder – экструдер, шприц-машина

extruder cooker – экструзионный варочный аппарат

cook (v.,n.) – подвергать/ся тепловой обработке; варка, варщик, оператор

2. paste [peist]; pasty – паста, тестообразная масса; пастообразный

pasta [‘pastə] – 1) макаронные изделия; 2) макаронное тесто; 3) блюдо из макарон

macaroni products – макаронные изделия

spaghetti – спагетти

noodle/s – лапша

vermicelli – вермишель

3. die – матрица, штамп

jacket – кожух, рубашка (парового котла)

to jacket – надевать кожух

4. unit food processing (operation) – составная операция пищевых производств

5. cost – стоимость

6. ready–to–eat foods – пищевые продукты, готовые к употреблению

7. barrel – барабан

8. processing system – технологическая система

PRE–TEXT EXERCISES