Living Factories

1. Living Factories

2. Describe the advantages of immobilization and how it is used in continuous flow processing Compare continuous flow and batch processing methods Know that bacteria ferment lactose sugar in milk and make it sour Describe how brewers provide the best conditions for yeast Know that bacteria are needed for cheese and yoghurt production Explain why barley is malted before it is used by brewers State that beer, wine, and bread production depend on yeast Explain batch processing Describe and explain why precautions are taken when working with micro-organisms in a laboratory Explain how contamination by resistant spores is prevented State the word equation for fermentation of glucose by yeast Compare anaerobic and aerobic respiration Identify yeast as a single-celled fungus, which uses sugar as food

3. What is biotechnology? Use of living cells to make products useful to humans.

4. Alcohol Quorn Enzymes Insulin Antibiotics Uses of biotechnology Dairy (cheese, yoghurt) Bread

5. There are 3 types of micro-organisms: Bacteria Virus Fungi

6. Micro-organisms need water, warmth and nutrients (oxygen) to grow. A group of micro-organisms growing together is called a colony. Colonies all grow in different shapes and colours depending on the micro-organisms growing.

7. Use Bunsen to flame loops and necks of culture bottles Autoclave equipment after use, and cultures before disposal Wash hands before and after use Clean bench with disinfectant Wear a lab coat Use safe cultures Autoclave equipment and growth media Precautions Incubate cultures below 37oC

8. Yeast Yeast is a single-celled fungus, which grows asexually by budding. Yeast is important to us as it is used in bread and brewing.

9. yeast Glucose Carbon dioxide + Ethanol Yeast respires aerobically to provide energy. The word equation is the same as before. Write it down! Yeast can also respire anaerobically. This process is also called alcohol fermentation.

10. Brewing In brewing, barley starts to germinate to turn starch into fermentable sugars (e.g. Maltose). This process is called malting. The barley is then heated to stop enzymes breaking down the sugars. This is called kilning. Yeast can then ferment the sugar into alcohol. Hops are added to give flavour to the beer, and sometimes extra carbon dioxide is added to give the beer ‘fizz’.

11. Batch Processing In batch processing, all raw materials are placed in a fermentation vessel and left. When fermentation stops, the product is removed. Equipment must be thoroughly cleaned between batches. This is a disadvantage as no product is made during this time.

12. Bread In bread making, yeast ferments sugar to make carbon dioxide and alcohol. Carbon dioxide causes the bread to rise. Alcohol evaporates in the heat.

13. Milk Bacteria in fresh milk feed on lactose sugar and convert it to lactic acid. Lactic acid gives milk a sour taste. Souring of milk is another example of fermentation. This type of fermentation is called lactic acidfermentation. bacteria Lactose Lactic acid

14. Yoghurt Milk can be changed into yoghurt using lactic acid fermentation. Lactic acid causes milk to go thicker and gives yoghurt its sour taste. To make yoghurt, milk is heated to kill pathogens, and then cooled before adding a starter culture. The milk is cooled to the optimum growing temperature of the yoghurt forming bacteria. The mixture is then covered to prevent bacteria entering. After incubation, the yoghurt is placed in a fridge to set.

15. Cheese Bacteria ferment milk to lactic acid. Rennet is also added which causes milk to be separated into curds and whey. Solid curds is left to mature with bacteria to ripen and become cheese.

16. Continuous Flow In continuous flow, enzymes are trapped in a jelly bead, and packed into a container. The substrate is the trickled into the top passing over the enzyme. As it does, enzymes catalyse the reaction producing the products, which can be collected at the bottom. This is better than batch processing, as the enzymes can be re-used, the products are easier to separate, and the process does not need to be stopped. This process can be used in fermentation, as yeast can also be trapped in the jelly beads.