Biotechnology

1. Biotechnology Standard Grade Biology A- Living Factories

2. What is biotechnology? Brewing beer/ wine Baking bread Making animal food Sewage disposal Cheese & yoghurt Biofuels May help with future challenges in food production and health Antibiotics Using living cells from plants, animals, bacteria and fungi (microbes) to produce useful substances or dispose of waste:

3. Doh! Beer!! The raising of dough and the manufacture of beer and wine depend on the activities of yeast. • In baking, yeast produces carbon dioxide gas. • This makes the dough rise. • Baking the bread finally kills the yeast and cooks the dough.

4. Beer & wine Wine production in the Auvergne region of France Yeast is used to produce alcohol in these drinks. • Wine is produced in: • Europe • South America • South Africa • Australia & NZ and more…

5. Wine-making • The grapes are harvested, crushed and allowed to ferment. • Yeast converts most of the sugars to alcohol and releases carbon dioxide (CO2) which is allowed to escape. • Grapes are pressed or dead yeast removed and a 2nd fermentation occurs, producing wine which is often aged in casks before bottling. http://en.wikipedia.org/wiki/Wine_production

6. Steps in wine-making 1. Crush the grapes to release juice 2. Filter grape juice into sterilised fermentation flasks 3. Add yeast. 4. CO2 bubbles escape through air lock Yeast grows using sugar and forms alcohol 6. Wine siphoned into bottles 5. Alcohol build-up kills yeast and stops fermentation

7. What is yeast? It reproduces asexually by budding Yeast is a single-celled fungus, which can use sugar as food. It occurs naturally as a ‘bloom’ on fruit. microscopes Yeast uses the sugars glucose or maltose as a food source for respiration.

8. How does yeast do this? Glucosecarbon dioxide + alcohol + energy For baking For drinks For yeast Yeast can respire aerobically: (glucose + O2CO2 + H2O + lots energy) In conditions of limited or no oxygen it respires anaerobically. This is also called fermentation: Using a word equation, state the process of fermentation of glucose by yeast.

9. Comparing respiration Describe the process of anaerobic respiration and compare it with aerobic respiration. Learn the equations for both processes and: Aerobic Anaerobic • oxygen always required • efficient method • releases lots of energy. Sugar completely broken down (CO2+H2O) • oxygen never required • inefficient method • releases little energy. Chemical energy locked up in alcohol (C2H5OH)

10. Fermentation experiment 2 spatulas yeast, 15 ml warm water, 2 spatulas sugar into a boiling tube or conical flask (sidearm) Put balloon over the top. Leave for 30 minutes. Then remove balloon and bubble through limewater and/or pour gas from tube into it & shake. If done in thermos flask (48h) • Temperature increased • Bicarbonate indicator goes from red to yellow (CO2) • Distillation at 80oC produces ethanol (alcohol)

11. Making bread rolls Rub 350g plain flour, teaspoon butter, pinch salt. Mix 235ml warm water, 1 teaspoon sugar, 2 teaspoons yeast. Stir, allow to sit for 10 minutes. Knead for 10 minutes to form dough. Cover and leave in warm place for 1h30min. Knead for further 3 min, divide into rolls, put on greased baking sheet, cover and leave for 30min, Cook at 230oC for 12 minutes.

12. Beer-making Aviemore Black Isle Brewerynear Inverness Uig, Isle of Skye Inveralmond Brewery, Perth

13. Main steps in brewing • Malted barley is mixed with warm water, then flavoured with a plant called hops. • Germinated barley seeds release sugar (maltose). • Yeast is added to the fermenter. • Yeast uses the maltose from the malted barley to make alcohol and carbon dioxide. • The alcohol is filtered and pasteurised to kill unwanted organisms. • The beer is bottled. http://www.cairngormbrewery.com/brewing_art.htm http://www.undiscoveredscotland.co.uk/munlochy/blackislebrewery/index.html

14. 1 Explain the need for malting of barley before use by the brewing industry. Malting is the controlled germination of cereals by a process of steeping in warm water, then drying, repeated several times. (Sumerians 2500BC) Barley Seed Embryo shoot Food store (starch) Seed coat Why bother? Yeast cannot feed on starch. But yeast can feed on maltose which is produced during the malting process.

15. Germination underway A steep filling with grain Germination almost completed Final product- malted barley Kiln being loaded (heating halts germination) barley enzymes yeast enzymes fermentation Maltose Glucose Alcohol Starch

16. Hops Hot water Mill (malted barley) Copper Wort Mash tun Hopped wort Fermenting vessel Live yeast Beer Racking into Casks Conditioning tank Beer to pub / retailer 1 Main steps in commercial beer-making As told by Cairngorm Brewery, Aviemore 2 3

17. Cairngorm Brewery, Aviemore The brewery opened in 1997 and currently has a capacity of 90 barrels (3240 gallons) fermenting and 90 conditioning.

18. Fermenters • Yeast added at this stage. • Carefully controlled conditions of oxygen, temperature and pH. • Yeast activity monitored frequently. Before fermenting there must be sterile conditions to prevent growth of unwanted bacteria

19. Temp: 10-18oC • pH: 7 • Adequate supply glucose & oxygen Describe how commercial brewers provide the best growing conditions for yeast. 2

20. Batch processing 3 Explain what is meant by the term “batch processing”. is when a large reaction vessel (fermenter) is filled with a batch of nutrients (raw materials) and a micro-organism (inoculum) added. The process comes to an end when the micro-organisms stop growing (>5% alcohol). The fermenter is emptied, products separated and purified. It is then cleaned, sterilised and the process repeated. Conditioning tank (maturing)

21. Alcohol Don’t confuse it with Methanol CH3OH ! The chemical produced during fermentation is one member of a family of substances Can cause considerable irritation to eyes. "One-off" consumption of small amounts of ethanol is not likely to be harmful, but consumption of large amounts can be (and has been) fatal. Chronic (long-term) ingestion of ethanol may lead to damage to a variety of organs, such as the liver, and may increase the risk of cancer. Ethanol molecule C2H5OH Methanol is toxic. If ingested or inhaled it can cause a wide range of harmful effects, from sickness, heart and liver damage to reproductive harm, blindess or death. It is often a component in "bootleg" liquor (illegally brewed and distilled alcohol) and there have been numerous cases in the past in which the consumption of such a drink has been fatal.

22. Check Test 1. The raising of dough and making of alcohol depend on: 2. Which of the following can yeast use as food? • Amoeba • Bacteria • Yeast • Viruses • Carbon dioxide • Ethanol • Oxygen • Sugar 3. During germination of barley, starch is converted into: 4. Yeast is best described as a: • Group of bacteria • Single cell fungus • Single cell amoeba • Group of viruses • Oxygen • Alcohol • Carbon dioxide • Maltose C D D B

23. 5. Which growing conditions should brewers provide for yeast to grow well? • Light, temperature, oxygen • Food supply, temperature, light • Temperature, oxygen, food supply • Ethanol, oxygen, food supply 6. The process of fermentation by yeast is shown: • Glucose (yeast) ethanol + carbon dioxide + energy • Ethanol (yeast) glucose + carbon dioxide + energy • Glucose (bacteria) ethanol + carbon dioxide + energy • Ethanol (bacteria) glucose + carbon dioxide + energy 7. A useful product from fermentation of glucose by yeast is: • Oxygen • Nitrogen • Air • Carbon dioxide 8. Alcohol is: • Methanol B. Maltose • C. Ethanol D. Propanol C A D C

24. Fermentation of milk bacteria Lactose lactic acid The milk becomes more and more acidic, lowering the pH and making it taste sour The souring of milk is a fermentation process which happens when the bacteria in the milk use the milk sugar (lactose). It is their food source during anaerobic respiration. Explain the souring of milk in terms of bacterial fermentation of lactose.

25. Raw materials 3000 BC Babylon Water buffalo Products Cheese (over 700 types in UK alone) Fromage frais Cottage cheese Yoghurt Glenlivet, Ballindalloch Auchtertool, Kirkaldy Stephen Mitchell 1st Scottish farmer • Raw milk • Skimmed • Pasteurised Milk-producing animals: • Cow • Goat • Sheep • Buffalo • Horse • Camel

26. Product- yoghurt The manufacture of cheese and yoghurt depends on the activities of bacteria. Yoghurt-making uses 2 species of bacteria to ferment milk (often low-fat). They are added as a starter culture and produce lactic acid. When the pH drops to 4.4 the proteins coagulate (thicken) producing yoghurt. Make your own yoghurt Upd8 Camel milk activity

27. Yoghurt production mixing Milk products Heat treatment at 90oC 1. 2. 3. Removes oxygen Kills harmful bacteria Changes milk proteins Yoghurt bacteria added Cooled to 40oC Ferment milk sugar (lactose) into lactic acid. Best temperature for growing yoghurt bacteria 1. 2. Give yoghurt its acid taste Credit: museum of brands Fermentation for 6 hours Storage tank at 4.5oC Slows down further bacterial fermentation

28. Good & bad bacteria Lactobacillus Streptococcus What do I look like? I’m a single-celled long slender rod. Where can you find me? In mouth and gut of healthy people, added to dairy products.What do I do? In yoghurts to keep your gut healthy and to keep the bad bacteria away.  What do I look like? I’m a spherical cell, can form chains. Where can you find me? In humans, horses, pigs and cows. In these hosts I’m found in the mouth, throat, skin, heart and muscle.What do I do? Mostly harmless but can give you a sore throat & scarlet fever. 

29. UK Cheese facts 10 litres milk makes 1kg cheddar Bought by over 98% households Favourite: Cheddar (55%) Henry II (1170) bought 10,240lbs We eat 545,000 tonnes pa, about 10kg per person In Charles I reign it was bespoke and sold before made! Coloured cheeses use red Annatto (E160b) from seed of a South American shrub (Lipstick Tree) 2nd place Mozzarella about 34% fat, concentrated sources of key nutrients inc calcium, protein and vitamins A, D and B12. 1901 Captain Scott’s Discovery took 3500lb cheddar to Antarctica

30. Product-cheese • Pasteurise milk to destroy bacteria. • Starter culture of lactic acid bacteria added. • Rennin (enzyme) added to milk to digest it. • This curdles the milk to form curds (solid) and whey (liquid). • 4. Curds and whey are separated. • 5. Curds are cut, salt added for flavour and to slow down the growth of bacteria. • 6. Moulded and matured for up to 3 years. http://www.wharffarmdairy.co.uk/cheese.html

31. G Davidson, Islay

32. Whey products Curd products Curds form the cheese but 1kg milk only gives 125g cheese. The remaining whey (875g) can be used for making other things such as: No micro-organisms Fermentation with Micro-organisms • Animal feeds • Lactose sugar • Whey butter • Methane (bacteria) • Alcohol (yeast) Pasteurising is boiling or ultra-heat treatment (UHT) of milk to prevent unwanted bacteria in milk growing and multiplying.

33. Check test 9. Look at the results of pH tests on two milk samples: Test tube X= pH 7.5, test tube Y= pH 4.0 • Tube X contains sour milk, tube Y contains fresh milk • Tube X contains fresh milk, tube Y contains sour milk • Both tubes contain fresh milk • Both tubes contain sour milk 10. The cheese & yoghurt industries depend on the activities of: 11. Which of the following pairs of foods are made by bacterial action? • Bacteria • Yeast • Amoeba • Viruses • Yoghurt, milk • Cheese, yoghurt • Yoghurt, ice cream • Cheese, ice cream B A B

34. Quick Test • What is biotechnology? • What kind of organism is yeast? • Write the word equation for fermentation using yeast. • 4. Why is yeast important in the baking industry? • Name the useful product of fermentation in the brewing industry. • Name the large vessel used by brewers when making beer. • Write the equation for the malting process in barley grains. • What is added to milk to make yoghurt? Using living cells to produce useful substances or dispose of waste A single-celled fungus Glucose  carbon dioxide + alcohol + energy Carbon dioxide produced causes the dough to rise Alcohol (ethanol) Fermenter Starch  maltose Bacteria

35. Webstuff http://www.visit-islay.com/biology/stg/biotech.html#rm Great revision notes plus on-line quiz and crosswords for all 3 biotechnology subtopics http://www.visit-islay.com/biology/stg/crosswords/lf.htm