1. ABBOTTS
BIOTECHNOLOGY

2. BIOTECHNOLOGY
the use of micro-organisms by humans to make substances, humans want
E.g. In the manufacture of food, antibiotics, biogas
These substances include:
Medicines
antibiotics and insulin
Food
Maas, bread, wine and cheese

3. Antibiotics
Antibiotics can be made naturally by a process called biosynthesis
It involves the formation of a chemical compound by a living organism
Natural antibiotics are made by fungi
E.g. Penicillium which grows on fruit
Streptomyces which grows in soil

4. INSULIN PRODUCTION
Insulin is a hormone which regulates the concentration of blood sugar
People suffering from diabetes mellitus cannot make insulin
Have to have daily injections of insulin
Used to get insulin from pigs
Today genetic engineering has produced bacteria which can make human insulin
Bacteria are grown in large vats
Insulin is extracted and purified

5. ANAEROBIC RESPIRATION
TRADITIONAL TECHNOLOGY
ANAEROBIC RESPIRATION
Many of these processes involve anaerobic respiration – respiration without oxygen
Sugars are changed into alcohol and carbon dioxide – alcoholic fermentation
During this process, in the presence of sugar, some bacteria and fungi produce:
fermented foods
alcoholic drinks
breads
Sugars are changed into alcohol
And large quantities of carbon dioxide

7. TRADITIONAL TECHNOLOGY IN FOOD PRODUCTION
SORGHUM BEER
MAAS
MAHEWU

8. ALCOHOLIC DRINKS - BEER
Beer is made by a process known as brewing
Dried, crushed germinating barley seeds (contain the sugar maltose), water, hops (for flavour) and yeast are mixed
Yeast respires anaerobically producing alcohol and carbon dioxide (gives beer the bubbles)
When fermentation is complete the excess yeast is skimmed off and is used to produce yeast extracts such as Marmite

9. MAHEWU Traditional South African non- alcoholic energy providing drink
TRADITIONAL SOUTH AFRICAN BEER
Traditional South African non- alcoholic energy providing drink
Made from fermented maize meal or sorghum, malt, yeast and water
Commercially available at supermarkets
Similar to mealie meal but with sugar changed to lactic acid during fermentation
Commercial preparations are often enriched with vitamins and minerals

10. ALCOHOLIC DRINKS - WINE
Wine is produced from grapes
Can be made from many other types of fruit
Yeast cells found on the grape skins ferment grape sugar turning it into alcohol and carbon dioxide
Grape juice is allowed to ferment
and bottled

12. BACTERIA IN THE FOOD INDUSTRY
Fermented dairy products
The bacterium Lactobacillus acidophilus causes pasteurised milk to ferment
Lactose is converted into lactic acid
Lowers the pH of the milk
Causes the protein caseinogen to coagulate starting process for making yoghurt and some cheeses
The increased acidity prevents the proliferation of pathogenic bacteria

13. BACTERIA IN THE FOOD INDUSTRY
Cheese making
An enzyme rennin is added to curdled (acidified) milk
Causes further coagulation forming curds and whey
Curds and whey are separated
Curds are drained and pressed into cheese
To produce a variety of cheeses, different incubation periods, milks and bacteria are used
Process is complicated
Can take from months to a year to complete

15. NON-DAIRY FERMENTED FOOD PRODUCTS
EXTRA
NON-DAIRY FERMENTED FOOD PRODUCTS
Acetic and lactic acid are produced by fermentation bacteria
The acids protect the food against decay
Fermented foods – pickles, olives, sauerkraut, cured meats and fish – are usually produced by lactic acid bacteria
Vinegar is produced by acetic acid bacteria acting on wine, cider or other alcoholic beverages to produce acetic acid

16. FUNGI IN THE FOOD INDUSTRY
Yeast and certain moulds are used in biotechnology
Yeast is a unicellular fungus
It is the smallest fungus but it is economically extremely important in the production of bread and alcoholic drinks

17. EXTRA
BREAD MAKING
Bread is made from a mixture of flour, a little sugar and yeast
During the process yeast ferments sugar and gives off carbon dioxide and alcohol
Carbon dioxide makes the dough rise while alcohol evaporates

19. THE END