Glenlola Collegiate School

1. Glenlola Collegiate School excellence through commitment, contribution and caring food & diet

2. LEARNINGOUTCOMES ALL MUST… Know what food is used for Compare combustion & respiration Know the equation for respiration

3. Watch the video & jot down what food is used for on the white board Share with a partner Discuss as a class starter activity

5. Food is a source of chemical energy in humans Energy is released from food during respiration Respiration occurs in side all cells

6. compare combustion & respiration heat ENERGY ENERGY for growth oxygen oxygen respiration glucose + water +oxygen --> carbon dioxide + energy combustion fuel + oxygen --> carbon dioxide + water + heat energy

7. LEARNINGOUTCOMES ALL MUST… Investigate energy content of different foods Work safely & accurately Collect & analyse data Evaluate discussing reliability & validity

8. BT in clamp Thermometer Boiling tube 25cm3 water Mounted needle Comparing the energy content of different foods food

9. Method • Measure 25cm3 water into a boiling tube using a measuring cylinder. • Measure and record the temperature of the water, using a thermometer. • Weigh 2g of each food. • Place the food on the mounted needle. • Heat the food sample in a blue Bunsen burner flame until it begins to burn, then hold it under the tube of water. • When the food has burned fully, measure the temperature of the water sample again and calculate the rise in temperature.

10. equipment • Boiling tube • Retort stand • Mounted needle • Bunsen burner • Heatproof mat • Safety glasses • Thermometer • 25cm3 measuring cylinder

11. risk assessment • Bunsen burner: • heating may cause food or water to spit onto skin or into eyes • Wear safety glasses and long sleeves • run under cold water or use eye wash & inform teacher • Hair may ignite in Bunsen flame • tie hair up • Cover with fire blanket or blazer to extinguish & inform teacher • Mounted needle: • Metal needles conduct heat from the burning food • Use a wooden needle or hold needle in clamp. • Run under cold water & inform teacher

12. Table for results

13. To calculate the energy given off by 2g of each food use the equation below: ENERGY (J) = mass of water (g) X 4.2 X temp rise NB. Water has a density of 1g/cm3, therefore 25cm3 water weighs 25g. ENERGY (J) = 25 X 4.2 X temp rise

14. To calculate the energy in 100g of the food energy in 100g = energy X100 mass of food 

15. Analyse data Which food contained the most energy? How do these results compare to the energy content on the packet? Can you explain the difference? •  Some of the energy heated the atmosphere. • Some of the energy heated the glass. • some of the energy remains in the food.

16. evaluate data How would you make the results more reliable? Repeat & find average How did you ensure you carried out a fair test? Only change one variable (food type) others stay same * same mass of food * same distance between the burning food and boiling tube * same volume of water.

17. LEARNINGOUTCOMES ALL MUST… explore & evaluate how the energy required by individuals is different.

18. Look at the bar chart of energy requirements for different people. Write down the factors which affect their energy requirements. starter activity

19. Energy needed per day by different people in different situations Energy /kJ People

20. factors affecting energy requirements

21. age teenagers usually needs more energy than elderly people

22. gender boys usually need more energy than girls

23. activity active people need more energy than less active people

24. the extra energy is obtained from meals containing lots of carbohydrates These are broken down to release the energy in respiration

25. pregnant women have high energy needs due to the high rate of growth of the developing foetus

26. in science ENERGY IS MEASURED IN joules (j) kilojoules (kj) most food packets also measure energy in calories

27. sort activityWho needs most energy and why?Use notes & text book

28. recommended daily amounts of energy Model answer 1. Energy requirement female15-17 years = 9.0 MJ a. Energy requirement male 15-17 years = 12.0 MJ, so I need less energy b. Energy requirement female desk worker = 9.5 MJ, so I need less energy c. Energy requirement very active male worker = 14.0 MJ, so I need much less energy 2.The energy needs of males increase between 9 and 17 years because they are growing and producing muscle.

29. 3. The biggest increase in energy requirements is for males (27MJ) and females (24 MJ) between 1 and 9 years. This is because they are growing fastest. 4. The pregnant woman needs most iron and calcium. Iron is needed to make red blood cells to carry oxygen to the foetus. Calcium is needed for the baby to develop strong teeth and bones.

30. LEARNINGOUTCOMES ALL MUST… Examine food content from food labels

31. Read the ingredients for a common food listed on the next slide. Would you eat this food? Why? Can you guess what the food is? starter activity

32. INGREDIENTS: WATER (75%), SUGARS (12%) (GLUCOSE (48%), FRUCTOSE (40%), SUCROSE (2%), MALTOSE (<1%)), STARCH (5%), FIBRE E460 (3%), AMINO ACIDS(<1%) (GLUTAMIC ACID (19%), ASPARTIC ACID (16%), HISTIDINE (11%), LEUCINE (7%), LYSINE (5%), PHENYLALANINE (4%), ARGININE (4%), VALINE (4%), ALANINE (4%), SERINE (4%), GLYCINE (3%), THREONINE (3%), ISOLEUCINE (3%), PROLINE (3%), TRYPTOPHAN (1%), CYSTINE (1%), TYROSINE (1%), METHIONINE (1%)), FATTY ACIDS (1%) (PALMITIC ACID (30%), OMEGA-6 FATTY ACID: (LINOLEIC ACID (14%). OMEGA-3 FATTY ACID (LINOLENIC ACID (8%), OLEIC ACID (7%), PALMITOLEIC ACID (3%), STEARIC ACID (2%), LAURIC ACID (1%), MYRISTIC ACID (1%), CAPRIC ACID (<1%)), ASH (<1%), PHYTOSTEROLS, E515. OXALIC ACID, E300, E306 (TOCOPHEROL), PYLLOQUINONE, THIAMINE, COLOURS (YELLOW-ORANGE E101, (RIBOFLAVIN), YELLOW-BROWN E160a), FLAVOURS (3-METHYLBUT-1-YL, ETHANOATE, 2-METHYLBUTYL ETHONOATE, 2-METHYLPROPAN-1-OL, 3-METHYLBUTYL-1-OL, 2-HYDROXY-3-METHYLETHYL BUTANOATE, 3-METHYLBUTANAL, ETHYL HEXANOATE, ETHYL BUTANOATE, PENYL ACETATE), 1510, NATURAL RIPENING AGENT (ETHENE GAS).

34. Examine food content • In pairs use the food labels provided to jot down the common information provided about the foods. • Weight • Ingredients • Energy content

39. Read the article: Food labelling: Consistent system to be rolled out Answer the following question: Describe the guidelines daily amounts of food for mean and women. Why are these only ‘guidelines’? How will the new labelling system make it easier for people to make healthy choices? Look at the food label in the article and consider the balance of nutrients show. Is this a healthy option for breakfast?

40. LEARNINGOUTCOMES ALL MUST… State the function and sources of Proteins Fats Carbohydrates Vitamins C & D Minerals calcium & iron Water Fibre

41. protein fat fibre water Carbohydrate vitamins minerals starch & sugar food groups C & D calcium & iron

42. Sort activity • Sort the information cards to correctly link each food type using the following headings: • Food type • Function • Example of food type • Use the text book to check your answers. • Photograph & stick in book.

43. PROTEIN

44. for growth & repair of body cells

45. beef, lamb, pork, chicken, duck, fish, beans, tofu, nuts

46. CARBOHYDRATE sugar

47. CARBOHYDRATE starch

48. for fast energy release

49. for slow energy release

50. potato, bread, pasta, rice