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

Research Question:- How does the time of boiling effect the amount of vitamin C in food

Extracts from this document...


Name : Mohd Haziq Al-Hakim Bin Hamirruddin Class : M08F Date : 18 July 2009 Title : Measuring the concentration of vitamin C Introduction:- Refer to Biology HL handbook page 159 Aim:- To investigate the effect of the time of boiling on the amount of vitamin C in food Research Question:- How does the time of boiling effect the amount of vitamin C in food Hypothesis:- The longer the duration of boiling of the citrus fruit, the lower the concentration of vitamin C Variables:- Independent : Time of boiling of the citrus fruit. Different boiling time is used which is 0min (fresh), 10 min and 1 hour. Dependent : The concentration of vitamin C. Controlled : Type of citrus fruit, volume of lemon juice, volume of DCPIP and volume of glacial acetic acid Apparatus and Materials:- Refer to Biology HL handbook page 159 Procedure:- Refer to Biology HL handbook page 159 Data Collection:- Quantitative Data:- Duration of boiling the juice Trial Volume of titrated juice, cm3 (�0.1) ...read more.


1 cm3 of the mixture contains mg of ascorbic acid 1cm3 of the original lemon juice contains mg of ascorbic acid However, unit must be in mg/100cm3 mg must multiply by 100 Where V - Average volume needed to decolourise DCPIP solution For fresh juice, = = (5.00/ 112.4) x 100 = 4.45 mg/100cm3 For 10 min, = = (5.00/ 151.6) x 100 = 3.30 mg/100cm3 For 1 hour, = = (5.00/ 180.0) X 100 = 2.78 mg/100cm3 Discussion:- 1. This experiment is conducted to calculate the concentration of ascorbic acid (C6H8O6) or vitamin C in different samples of lemon juice. To find the concentration, we titrated the sample juice against 1 cm3 of 2-6 dichlorophenol indophenol (DCPIP). The ascorbic acid contained inside the sample juice will bleach the dark blue colour of DCPIP to become a colourless solution because of its strong reducing agent properties. It is assumed that 0.05 mg of ascorbic acid will reduce 1 cm3 of DCPIP, a value which has been internationally standardised. ...read more.


Limitations and Suggestion Limitations Suggestions There are only two numbers of trials. This can lead to inaccurate of the result obtained. We can overcome this problem by increasing the number of trials for this experiment so that a more accurate result can be obtains. Drops of DCPIP used might not be standardised. Thus may result in variation of the colour change of the indicator. The amount of DCPIP solution must be standardized to avoid variation of colour obtained. The indication of colour change varies from an experiment to the other. Thus this could result in inaccuracies. Standard colour of solution should be prepared and the person that should swirl the flask must be the same so that accurate result could be obtained Conclusion:- From this experiment, it is known that fresh lemon juice has the highest concentration of ascorbic acid or vitamin C. This shows that the longer we cook a fruit, the less concentration of vitamin C will present as heat will destroy ascorbic acid in our foods. Hypothesis is accepted. Reference:- * Biology for the IB Diploma, CJ Clegg, Hodder Murray Publication 2007 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology 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 International Baccalaureate Biology essays

  1. Marked by a teacher

    Neurology and Behaviour. Focus question: Is there an increase in the perception and ...

    5 star(s)

    These factors, genetic and environmental allow for an explanation as to possibly why the female participants of this study rated the images as more disgusting in average than the male participants did. 3.2 Evaluating Procedures Reliability This survey and the data obtained may not be seen as reliable due to the small number of participants involved from each gender.

  2. Research Question: Does the duration of exercise have an increased effect on a persons ...

    Results showed that since t-calculated was -11.06 ( well inside the rejection region) the average Heart Rate for increment one 0 seconds is significantly different than the average Heart Rate for increment two 45 seconds. While these results agree with what was expected to happen, it seems strange that after

  1. The effect of toliet cleaning products on E-coli ...

    One or both of the processes could have occurred for any of the solutions, and in the end both would end with the same result, the elimination of e coli growth. However it is important in future experiments that the individual process is identified as each has different implications (one is possibly more effective than the other).

  2. The Effect of Temperature on the Vitamin C Content of Lemon Juice

    lemon juice is needed to be added to the DCPIP to cause it to decolourise. The mean amount of lemon juice drops required to turn the DCPIP colourless at 20°C was 2.8, while at 60°C it was 16, this shows a marked increase in the number of drops of lemon

  1. How does cooking affect the amount of vitamin C in lemon juice?

    Trial Reading of burette (± 0.05 cm3) Initial Final Fresh lemon juice 1.0 1 1.30 34.10 1.0 2 1.10 33.50 10 minutes boiled lemon juice 1.0 1 3.20 45.10 1.0 2 4.10 44.70 1 hour boiled lemon juice 1.0 1 1.90 34.80 1.0 2 1.30 28.50 Table 1 The initial and final readings of burette in the titration.

  2. Effect of Incandescent, Fluorescent and LED lights at 900 lumens on the concentration of ...

    ________________ Each light bulb will be bought at wattage corresponding to 900 lumens hence, Incandescent light at 60 watts. Fluorescent light at 15 watts. LED light at 12 watts. ________________ Amount of light emitted (Lumens) is kept controlled in order to have reliable numbers when calculating the concentration of vitamin C remaining.

  1. Sleep is a normal part of human life. Investigate the neurobiological basis of normal ...

    Many hormones are secreted into the blood during sleep. For example, scientists believe that the release of growth hormone is related in part to repair processes that occur during sleep. Follicle stimulating hormone and luteinizing hormone, which are involved in maturational and reproductive processes, are among the hormones released during sleep.

  2. What is the effect of pH levels on the net production, given by the ...

    Take 1mL of Chlorella pyrenoidosa sample received and use wet-plating procedure for microscope observations. Record any observations. Fill a 50 mL beaker with 45 mL +/- 1 mL of distilled water to warm up DO probe before taking DO readings.

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