• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

All foods except vitamins and minerals contain stored energy. This energy is released and made available to living things during the chemical reactions of respiration.

Extracts from this document...

Introduction

Food Energy Background: All foods except vitamins and minerals contain stored energy. This energy is released and made available to living things during the chemical reactions of respiration. When food is burned it releases the same amount of energy in the form of heat, as it does when respired. The energy value of food is burned in a calorimeter. All the heat given off by the food is transferred to a known quantity of water, which rises in temperature. It takes 4.2 joules of heat to raise the temperature of 1g of water by 1oc. So the energy value of food is calculated by the formula; temperature rise x 4.2 x mass of water. A foods energy value is usually quoted in kilojoules: 1 kilojoule (1kj) = 1000 joules. These measurements give the potential rather than the actual energy value of a food. If you eat bread and butter, whose energy value is 1000kj, you do not get 1000kj of energy. ...read more.

Middle

potatoes fried in fat give three times more energy as potatoes boiled in water. A food calorimeter is used to find out how much energy there is in a sample of food: Prediction I think that the more energy a food contains then the more hotter the water will be. The food containing more fats will increase the temperature the most because... More fats>more energy>rise in temperature Plan To investigate how much energy a food sample contains I will need... Bowling tube Tongs Water Crushed food - crisps, cereal, rice, biscuit, noodles, bread Bottle top Thermometer Bunsen burner Pestle and mortar For the whole of the experiment I shall be wearing goggles. Firstly I am going to fill a boiling tube with 1/3 of water and then I am going to clamp it (see diagram). Then I shall record the temperature of the water. Then I am going to crush the food that I shall be using with a pestle and mortar and then place the food in a bottle top. ...read more.

Conclusion

I am not surprised that the noodles contained the least amount of energy, as the noodles don't have much fat. Order of energy given out: Most Crisps Cereal Bread Biscuit Rice Least Noodle Evaluation I think that the experiment was unreliable. The results were not very accurate due to the not so accurate amount of water and the foods, we could of weighed and made sure that we used the same amount of food for each one. Also we should of left the water to cool down between each food for the same amount of time. Instead of using a 1/3 of the boiling tubes amount in water we could of used 20ml of water. There were also difficulties in keeping the Bunsen burner alight and also keeping the food alight long enough to have an effect in the temperature of the water. Also to ensure the Bunsen stays alight and isn't affected by wind, e.g. place a shield around the Bunsen. Rajvir Nijjar 18083 1 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Food Technology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Food Technology essays

  1. Marked by a teacher

    The Importance of Vitamins and Minerals In the Human Body.

    4 star(s)

    yeast, molds, algae and some plants species, however it is needed by all organisms. In its active form it is attached to the active sites of four important enzymes, know as carboxylase. Figure 2 illustrates the chemical composition of a Biotin: Biotin Figure 2- Chemical Structure of the vitamin Biotin

  2. Explain the need for nutrition by living organisms.

    It has been suggested that this process is achieved when fats are broken down into fatty acids and glycerol through glycogenosis as previously described. In making fat ready for absorption, the product of the liver known as the bile, has to be secreted via the gall bladder.

  1. Which Crisps Have The Most Energy?

    the water the same for every crisp I burn, I will burn each crisp until it burns itself out and I will perform each experiment three times and take an average to make the experiment fair. Apparatus For this experiment I used Tongs, Safety Goggles, Test Tube, Bunsen burner, Safety mat, Measuring cylinder, Thermometer, Clamp stand, Clamp.

  2. heal and social unit 2

    This can then be used as a guide to the five BMI groups. UNDERWEIGHT BMI 19.0 AND BELOW NORMAL BMI 20-24.9 GRADE ONE OBESITY BMI 25-29.9 GRADE TWO OBESITY BMI 30-39.9 GRADE THREE OBESITY BMI 40 AND ABOVE WHAT IS A PEAK FLOW METER?

  1. Nutrients are split into two main groups, the macronutrients which contains carbohydrates, fats and ...

    Fat is very important in the formation of cell membranes nerve tissue. It provides a reserve of energy and helps to insulate the body against extreme temperatures. Stored fat also helps to cushion impact by protecting internal organs against shock.

  2. Measuring the Amount of Energy in Food.

    Insert thermometer into the test tube and record the temperature of the water 6. Attach test tube to clamp 7. Ignite the Bunsen burner, and if conducting experiment with a peanut, briefly hold the mounted needle above the flame (this will make it easier to skewer the peanut)

  1. I will look at six existing products which are already available and evaluate how ...

    This may also appeal to the consumer as it gives them different ranges of the type of microwaves that they could have. * The need for cost- the meal was �1.99 and may only serve one person, which makes it an expensive product, so therefore does not meet the need for cost.

  2. Business plan for a new service.

    There are still many dishes and recipes, as well as cuisines, too be brought to the market - and for the time being consumers are receptive to new options. Healthy annual sales growth has been a feature of the sector in recent years, as higher disposable incomes have enabled consumers

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work