Curtin University

1. INVESTIGATION TITLE: HOME
REMEDIES FOR REMOVING FOOD
COLOURING FROM SKIN
Robert Hunt
Student ID: 15518828
Date of Presentation: 29/03/2012

2. INTRODUCTION AND AIM
 Food colouring, or colour additive, is any dye, pigment or substance
that imparts colour when it is added to food or drink
 At the very basic level, all foods are either protein (meats, soy,
beans, etc.), carbohydrate based (grains, fruits, sugars) and fat
based. (Epp, D., 1995).
 This could be said of your skin as well, due to the fact that skin
shares similar functional groups
 Aim
 Which home remedy is the most effective at removing stains from
human skin.
 Changing the home remedies (chemical reactions) will reduce the
total amount of food colouring left on human skin.

3. MATERIALS
 Red Food Colouring – 5 Drops On A Skin Sample
 10cm By 10cm Squared Plastic Grid
 ¼ Tsp Household Bleach Diluted With ¼ Tsp Water
 ½ Tsp Water
 ½ Tsp Liquid Detergent
 ½ Tsp Lemon Juice
 ½ Tsp Salt Crystals
 ½ Tsp Brown Vinegar
 ½ Tsp Bi-carbonate Soda
 ½ Tsp Toothpaste
 Eye Dropper
 Wash Cloth
 Towel
 5 Bowls
 Cotton Wool Buds

4. VARIABLES, VALIDITY AND RELIABILITY
 Validity
 Data collection done over three day period under the same controlled variables.
 Reliability
 Human judgment can vary wildly between observers, and the same individual may rate
things differently depending upon time of day and current mood. (Shuttleworth, 2008).
 Use of plastic grid to reduce human judgement.
Independent Dependent Controlled
Home Remedies for stain removal Total percentage of stain removed •Temperature of the room
•Method of application
•Force in which the method is applied
to the skin sample
•Absorption time of the food colouring
and removal attempt
•Preparation of the skin sample
between each trial
•The use of the same food colouring
between each trial as different food
colourings have a different strength of
staining
•Time allowance for each methods
removal attempt.

5. COMPARISON OF RESULTS
Water and Liquid Detergent
Before Measuring Results
Lemon Juice and Salt Crystals
Before Measuring Results
Diluted Bleach
Before Measuring Results

6. COMPARISON OF RESULTS
Vinegar and Bi-carb Soda
Before Measuring Results
Toothpaste
Before Measuring Results

7. GRAPH AND TABLE OF RESULTS
100
90
80
70
60
50
40
30
20
10
0
Water and Lemon Juice Diluted Vinegar and Toothpaste
Liquid and Salt Bleach Bi-carb Soda
Detergent Crystals Trial 1 Trial 2 Trial 3 Average
Control -
Water and Liquid Detergent 95% 97% 93% 95%
Home Remedy 1 -
Lemon Juice and Salt Crystals 53% 55% 48% 52%
Home Remedy 2 -
Diluted Bleach 76% 84% 89% 83%
Home Remedy 3 -
Vinegar and Bi-carb Soda 86% 94% 90% 90%
Home Remedy 4 –
Toothpaste 44% 52% 39% 45%

8. DISCUSSION OF RESULTS
 Control group ( Water and liquid detergent) was most effective.
 Home Remedies most effective was Vinegar and Bicarbonate Soda
due to the chemical reaction (oxidation) that accords when mixing a
acid and case. Most consistent results.
 Diluted Bleach performed worse than expected since it can remove
tougher stains such as blood.
 Toothpaste was the worst with irregular results and not chemical
reaction. Abrasive friction only.
 Procter and Gamble (2005) states the oxidation process occurs due
to the chemical reaction that ‘cuts’ the stain molecules in smaller
pieces that are more easily removed when reacting with a acid or
base.

9. CONCLUSION
 Liquid detergent is the most effective since its mass produced
and sold to remove stains.
 Vinegar and Bicarbonate Soda most effective due to the
oxidation reaction that happens when mixing acids and bases.
 Human Judgement can affect the data collection if not
recorded properly as experiment is heavy on observation.
 Changing of food colour dye from red to another colour with a
weaker straining strength e.g. Yellow, will change results?
 Length of time allowed for absorption of food colouring altered
will affect total amount of food colouring stain removed.

10. REFERENCES
 Epp, Dianne N. (1995). Palette of Color Series: The
Chemistry of Food Dyes. Middletown, OH: Terrific
Science Press.
 Procter and Gamble (2005) What is Bleach?
Retrieved from
http://www.scienceinthebox.com/en_UK/glossary/bl
eaches_en.html
 Shuttleworth, Martyn. (2008). Validity and
Reliability. Retrieved from Experiment Resources:
http://www.experiment-resources.com/validity-and
reliability.html