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  • Message 1. 

    Posted by U15777206 (U15777206) on Sunday, 30th June 2013

    Hi can i have some help on these three questions and where i would be able to find them they are:

    How to measure the energy content of food and what units are used in the importance of fat in a healthy diet.

    Data to show the effect of fat and carbohydrate content on the amount of energy in snacks.

    How the fat and carbohydrate content affects the amount of energy in food.

    Is there any chance i can get these answers quite quickly im really stuck thankyou!

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  • Message 2

    , in reply to message 1.

    Posted by The Bitesize Science Teacher (U14392404) on Sunday, 30th June 2013

    Calorimetry is used to measure the energy content of food. See and the two pages after it. The standard unit for energy is the joule, J, but energy in food is also measured in calories.

    There is some confusion between calories and kilocalories (which are often just called 'calories') so you will be given the conversion factor needed in the exam: 1 kcal = 4.2 kJ.

    In general, fat contains more energy per gram than carbohydrates do:

    - fat contains 37 kJ/g
    - carbohydrates contain 17 kJ/g

    So food containing lots of fat usually contains a lot of energy, compared to the same mass of food made up of carbohydrates. For example, 100 g of chips contains about three times more energy than 100 g of boiled potato.

    I hope this helps. smiley - smiley

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