This document discusses testing for the presence of monosaccharides like glucose and fructose using Fehling's solution. It introduces carbohydrates and monosaccharides, and explains that Fehling's solution turns copper ions blue but reduces to a red precipitate in the presence of aldehydes. The experiment tests various food samples in test tubes by adding Fehling's solution and observing color changes upon heating. Most samples showed positive results with brown, red, or orange colors, but pounded rice was negative, indicating it contained polysaccharides rather than monosaccharides. The conclusion is that monosaccharides were present in most samples tested.

1. Carbohydrates:Monosaccharides
By
Khanifah
Alvin Rifqi Rijal
Retno Wulandari

2. Carbohydrates:monosaccharides
1.Purpose
To test presence of a monosaccharides (simple
sugar) in this case glucose and fructose

3. 2.Introduction
Carbohydrates are an important source of energy for humans.These
compound are present in large enough quantities in plants such as beans ,potatoes,
and skin. Carbohydrates are widely prevalent in the plant kingdom, comprising the
mono-, di-,oligo-, and polysaccharides. The common monosaccharides are glucose,
fructose, galactose,ribose etc. The disaccharides, i.e., the combination of two
monosaccharides include sucrose,lactose and maltose. Starch and cellulose are
polysaccharides consisting of many monosaccharide residues. Cellulose is the most
abundant organic compound on this planet since it forms part of the cell wall in
plants.

4. Aldehydes (–CHO) and ketones ( = CO) are active groups in
carbohydrates. Carbohydrates contain many hydroxyl groups as well. The number
of hydroxyl groups varies with the number of carbon atoms. Monosaccharides
contain the free aldehyde or ketone group.Carbohydrate are actually and
empirically have the general formula Cn(H2O)n

5. FEHLINGS TEST
A second test reagent, Fehling's solution, is restricted to
the detection of aliphatic aldehydes. The reagent is a
deep-blue, alkaline solution containing a complex cupric
ion. Upon reaction with an aliphatic aldehyde, the cupric
ion is reduced to form cuprous oxide which is deposited
as an orange to red precipitate.

6. 3 Tools and Materials
• TOOLS:
• Methylated spirit burner ,three legs and
asbestos
• 1L beakeras water bath
• Test Tube

7. Tools
No Nama Alat Gambar
1 Methylated spirit burner ,three legs and
asbestos
2. Beker Glass
3. Test tube

8. #Materials
no Materials picture
1 SOLID FOODS
--sugar
--biscuits
--breads
--bananas
-Nasi
2. LIQUID FOODs
-Honey
-syrup
-milk
--tea
3 Fehling a and fehling B solution

9. Incorporate liquid food samples and samples of solid food that has been refined
into a test tube
Add 3 drops of Fehling Fehling A and B into each test tube
Observe the color change
Lay the test tube in boiling water bath mounted above the burner methylated
Replace the test tube with tube clamp
Observe the final color of the sample
Procedure

10. • Procedure

11. Observational data

14. Discussion
The puropse of the experiments is to test the
presence of monosaccharides.in this case is
glukose and fructose. First ,all sample are mashed
and add it with fehling a and fehling b solution.
The initial color of sample can not be used
because it has not reacted. The initialcolor is
mixture between fehling and sample so, the color
in each sample is different. The final color is the
indicator of monosaccharides.

15. the result of the experiment is almost of
the sample had high monosaccharides except
the pounded rice. When it was heated in the
boiling water, it results blue color. It caused
that the sample of founded rice still in
polysaccharides form. It’s not react with
ptialine before.then, the chewed rice that
reacted by ptialine,had high monosaccharides
because the ptialine change amilum in the rice
tobe monosaccharides.

16. • Almost of the sample had color brown,red
brick and orange. It indicates that the sample
had high monosaccharides. The reaction
between sample and the fehling solution is

17. Conclusion and suggestion
• Conclusion
• Almost all sample had high monosaccharides
except pounded rice that had zero
monosaccharides. Monosaccharides presence
indicates by brown ,red brick and orange
sample in our experiment

18. Suggestion
• Practican should know the concept of
experiment
Practicanshould be aware when doing
experiment

19. Bibliography
J scarlet,Andrew.199.Collage Chemistry.New
York:Hendry holt and company
O’caonnor,Raymond F.1974.Chemical principles
and their biological
implication.Canada:Hamilton Publishing
Company
Lecturer Teamof Basic Chemistry.2014.Chemistry
Lab Manual Of Biology.Semarang:UNNES