Nutritional properties

Nutritional Properties
Aim: To investigate, realizeand deduce through the magnitude of color change,
the nutritional properties ranging from highly present to traces of simple sugars,
starch, proteins, fatsand non-reducing sugars in a controlled amount ofpeanuts,
banana, potato and milk.

Hypothesis:
Simple sugars test: It is predicted that banana and milk will turn orangish red
because of their atomic build up of carbon, hydrogen and oxygen.

Non-reducing sugars test: it is predicted that peanuts and potato will turn redish
to indicate that they contain non-reducing sugars because they contain
disaccharide sugars.

Starch test: It is predicted that peanuts, banana and potato will turn positive
(bluish black), this is because they contain atoms of carbon, oxygen and
hydrogen.

Protein test: It is predicted that most if not all food pieces will turn purple
because most of them contain atoms of carbon, oxygen, hydrogen. And the ones
(milk, banana and egg yolk) that contain small amounts of sulphur and nitrogen,
which will make the difference.

Lipid’s test: It is predicted that all the food pieces will turn milky white because
they contain atoms of carbon, hydrogen and oxygen.

Variables-
Simple Sugars:
Type of Variable How Units
Variable

IV Mass of peanuts, Use a weighing scale to +- 0.01 gms
banana and potato measure the weight
IV Volume of Milk and Use a measuring cylinder to +- 0.01 ml
Glucose measure the volume
IV Time in the water bath Use a stopwatch to measure +- 0.1 Seconds
and shaking the test the time.
tube
DV Change in color Record the beginning color
and end color. Use the color
of the Glucose solution as a
benchmark
CV Volume of water Measure the volume of +- 0.1 ml
water using a measuring

cylinder.
CV Volume of benedicts Measure the volume of +- 0.1 ml
solution benedicts solution using a
measuring cylinder.
CV Water Temperature of Measure the temperature +- 0.1* Celsius
the bath using a thermometer

Non-Reducing Sugars:

Variable

Sucrose measure the volume
IV Time in the water bath Use a stopwatch to measure +- 0.1 Seconds
and shaking the test the time.
tube
of the Sucrose solution as a
benchmark
CV Volume of HCl Measure the volume of HCl +- 0.1 ml
using a measuring cylinder.
CV Volume of benedicts Measure the volume of +- 0.1 ml
solution benedicts solution using a
measuring cylinder.
CV Volume of Measure the volume of +- 0.1 ml
Sodiumbicarbonate Sodium bicarbonate using a
measuring cylinder.
CV Water Temperature of Measure the temperature +- 0.1* Celsius
the bath using a thermometer
Starch:
Variable

IV Volume of Milk Use a measuring cylinder to +- 0.01 ml
measure the volume
benchmark

CV Volume of iodine Measure the volume of +- 0.1 ml
solution iodine solution using a
measuring cylinder.

Proteins:

Variable

IV Volume of Milk and Egg Use a measuring cylinder to +- 0.01 ml
Yolk measure the volume
IV Time taken while Use a stopwatch to measure +- 0.1 Seconds
shaking the test tube the time.
of the Sucrose solution as a
benchmark
CV Volume of water Measure the volume of +- 0.1 ml
water using a measuring
cylinder.
CV Volume of potassium Measure the volume of +- 0.1 ml
hydroxide benedicts solution using a
measuring cylinder.
CV Volume of copper Measure the volume of +- 0.1 ml
sulphate Sodium bicarbonate using a
measuring cylinder.

Ethanol:
Variable

Glucose measure the volume
IV Time taken while Use a stopwatch to measure +- 0.1 Seconds
shaking the test tube the time.
benchmark
CV Volume of distilled Measure the volume of +- 0.1 ml
water distilled water using a
measuring cylinder.

CV Volume of ethanol Measure the volume of +- 0.1 ml
ethanol using a measuring
cylinder.

Generic Materials (Materials 5 ml x Glucose Solution
Required for all 5 experiments): 5 ml x Sucrose Solution
8 x Test Tubes
5 x 5 grams of Potato Pieces 1 x Stop watch
5 x 5 grams of Banana Pieces 100 ml x Ethanol
5 x 5 grams of Peanuts 1 x Water Bath
5 x 5 ml of 100% Fat, Unprocessed 1 x Water
Cow’s Milk 1 x Pipet
100 ml x Benedicts Solution 1 x Grinding Bowl
100 ml x Iodine Solution 1 X Grinding Tool
100 ml x Hydrochloric Acid 3 x Measuring Cylinder
100 ml x Sodium Bicarbonate 1 x Medium Sized Egg Yolk
100 ml x Potassium hydroxide 2 x White Tiles
solution
100 ml x Copper sulphate solution

Procedure:
To Test-

For Simple Sugars:

1. Gather all the material.
2. Place one piece of potato, banana and pour 5 ml of milk and glucose into separate test
tubes.
3. Grind the 5 grams of peanuts.
4. Place the grinded peanuts in a test tube.
5. Label the test tubes P (Potato), B (Banana), M (Milk), G (Glucose) and p (Peanuts).
6. Add 2 ml of water into each of the test tubes.
7. Gently shake the test tube for about 30-60 seconds.
8. Add 2 ml of Benedict’s solution into all the test tubes.
9. Place the test tubes in a rack and then into a water bath (100* Celcius)
10. After 5 minutes remove the rack and place it on the clean counter.
11. Take down the color change

For non-reducing sugars:

2. Place one piece of potato, banana and pour 5 ml of milk and sucrose into separate test tubes.
5. Label the test tubes P (Potato), B (Banana), M (Milk), S (sucrose) and p (Peanuts).
6. Add 2ml of HCl into each of the test tubes.

7. Place the test tubes in a rack and then into a water bath (100* Celsius)
8. Observe the test tubes and wait till the solution begins to fizz.
9. When fizzing is observed, take out the test tubes.
10. Add 5 ml of sodium bicarbonate solution in each test tube until the content stops fizzing
11. Then add 5 ml of Benedict’s solution in all the test tubes and boil them for 5 minutes
1. A red colour would indicate that there is now reducing sugar in the food, which was produced
from non-reducing sugar
2. Take down any color change.

For starch:

2. Place the piece of potato and banana on sperate tiles.
4. Place the grinded peanuts and milk in a test tube.
5. Add 5 drops of iodine solution on each of the food items.
6. Take down the color change

For Protein:

2. Place one piece of potato, banana and pour 5 ml of milk into separate test tubes.
5. Label the test tubes P (Potato), B (Banana), M (Milk) and p (Peanuts).
6. Add 2ml of water in each test tube.
8. Add 2ml potassium hydroxide solution in each test tube.
9. Using a pipet add two drops of copper sulphate solution.
11. Note down any color change.

For Lipids:

2. Place one piece of potato, banana and pour 5 ml of milk and egg yolk into separate test tubes.
5. Label the test tubes P (Potato), B (Banana), M (Milk), E (Egg Yolk) and p (Peanuts).
6. Add 5 ml of pure ethanol in each test tube.
8. Add 2 ml of distilled water in 4 other test tubes.
9. Pour the liquid part, (no solids) from all the tubes into the tubes containing distilled water.
10. Take down any color change.

Risk Assessment:
Ethanol:
Ethanol is a highly flammable and harmful substance. If ingested, it may be fatal and may be absorbed
through the skin. The vapours can irritate the eyes. Ethanol may cause eye damage, nausea, dizziness,
headache and central nervous system depression. If ethanol comes in contact with skin, flush with
large amounts of water for at least 15 minutes. You should also remove contaminated clothing and

shoes, and wash before reusing. If the substance is inhaled, move to fresh air and give respiratory aid if
needed. For ingestion, give large amounts of water and call a physician. You should always shut off
ignition sources when using ethanol. Always wear eye protection, a lab coat and gloves.1
Hydrochloric Acid:
Hydrochloric acid is highly acidic, nonflammable, corrosive and poisonous solution of hydrogen chloride
and water. Persons working with or around hydrochloric acid should strictly adhere to safety
precautions. These include wearing properly fitting safety glasses and gloves and ensuring proper
ventilation.2

Benedicts Solution:
Eyes Hazardous in case of eye contact (irritant). Inflammation of the eye is
Characterized by redness, watering, and itching.
Skin Hazardous in case of skin contact (irritant). Skin inflammation is
Characterized by itching, scaling, reddening, or, occasionally, blistering.
Inhalation Hazardous in case of inhalation. May be hazardous in case of inhalation
(lung irritant).
Ingestion May be hazardous in case of ingestion.3
Copper sulphate:
Copper sulphate is an irritant and damages the environment if not disposed of correctly.4

Sodium Bicarbonate:
Taking sodium bicarbonate involves consuming a large amount of sodium, which can elevate blood
pressure, aggravate heart disease and lead to edema, or swelling of the legs and feet due to fluid
retention, according to Jackson Siegelbaum Gastroenterology. Anyone on a sodium-restricted diet and
people with high blood pressure, cardiovascular disease or kidney disease should not take sodium
bicarbonate. In addition, because edema is relatively common during pregnancy, pregnant women
should not take sodium bicarbonate.5

Observation:
Simple sugars test:
Sample Quantity Color Change Positive for Simple
Sugars?
Peanuts 5g Brownish Blue No
Milk 5 ml Orange Yes
Banana 5g Orangish red Yes
Potato 5g Bluish Black No
Glucose 5 ml Orangish red Yes

Non-Reducing Sugars test
Sample Quantity Color Change Positive for Non-
Reducing Sugars?
Peanuts 5g Orangish red Maybe
Milk 5 ml Red Yes
Banana 5g Red Yes
Potato 5g Orangish red Maybe
Sucrose 5 ml Red Yes

Starch test
Sample Quantity Color Change Positive for
Starch?
Peanuts 5g Bluish Black Yes

Milk 5 ml Browish White No
Banana 5g Bluish Black Yes
Potato 5g Bluish Black Yes

Protein test
Sample Quantity Color Change Positive for
Protein?
Peanuts 5g Light Blue Maybe
Milk 5 ml Whitish Purple Yes
Banana 5g Very Light Purple Yes
Potato 5g Light Blue No
Egg Yolk 5 ml Purple Yes

Lipids test
Sample Quantity Color Change Positive for Fats?
Peanuts 5g Cloudy white Yes
Milk 5 ml Milky suspension Yes
Banana 5g Cloudy white Yes
Potato 5g Milky suspension Yes

Conclusion: To conclude I would like to state that results were mostly in accordance with the
hypothesis. In the simple sugars test milk, banana and glucose tested positive for simple sugars and
peanuts and proteins only had traces. In the non-reducing sugars test milk, banana and sucrose tested
positive and peanuts and potato contained more than trace amounts of non-reducing sugars. In the
starch test, peanuts, banana and potato tested positive whereas milk displayed only trace amounts of
starch. In the protein test, milk, banana and egg yolk tested positive, whereas peanuts displayed more
than trace amounts and potato displayed trace amounts of protein. In the lipids test, all the solutions
turned into shades of white whereas according to research potato has most fat.

Evaluation: This experiment benefited my learning in numerous ways. First of all it has significantly
enhance my lab report writing skills since this is my biggest lab yet. This experiment covered several
topics at once and has taught me a lot amount nutritional properties and where to find them. We used
several dangerous chemicals such as ethanol, hydrochloric acid, etc and managed to use them
effectively to gain results. Better and more effective time management would have significantly helped
me. Teamwork is very important as it is vital to the success of a task, thus using each and every team
member’s strengths in areas in which they’re most comfortable and productive in would’ve also helped
the success of this experiment. Lab equipment such as test-tubes, measuring cylinders, etc weren’t
thoroughly rinsed and thus cross contamination has lead to varying, inconsistent results (another
element we need to work on) .Every assignment has scope for improvement; here are some of the
ways we could have improved the quality of our results: we could’ve used a colorimeter to judge the
colors; we could’ve repeated each test 3 times and we could’ve used a wider range of food items.

Bibliography
1
(2006), What are real life hazards of ethanol?, [on-line], Answers Corporation. Available from:
http://wiki.answers.com/Q/What_are_real_life_hazards_of_ethanol
[Accessed 1 April 2012]
2
Futch, J. (2012), Safety Hazards of Hydrochloric Acid [on-line], Demand Media, Inc. Available from:
http://www.ehow.com/list_6520818_safety-hazards-hydrochloric-acid.html

3
(2008), Hazards of Benedict's solution? [on-line], Answers Corporation. Available from:
http://wiki.answers.com/Q/Hazards_of_Benedict's_solution
4
(2009), The hazards and risks of copper sulphate? [on-line], Yahoo Inc. Available from:
http://uk.answers.yahoo.com/question/index?qid=20081204115039AA
5
Moore, S. (2011), WHAT ARE THE DANGERS OF SODIUM BICARBONATE?
[on-line], Demand Media, Inc.
Available from: http://www.livestrong.com/article/254063-what-are-the-dangers-of-sodium-
bicarbonate/

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