Tstl Ee Eloise S S Pta

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Concernant la présentation orale.

La durée est un peu trop longue (6:40 mins au lieu de 5:00 mins!),

Attention Ă  bien prononcer le morphème –ed : "excreted by aphids…", " that may be indicated on..", "solution is poured into the beaker", "is poured", "will be take =} taken, "the honey studied", "which is included"

Quelques erreurs Ă  Ă©viter comme "it's contain =} It contains, "each honey has its own personality" =} characteristics, "My problem problem-question is : does….", "6 experiences " =} 6 experiments, "this results are constist????"

Certains mots dans ces 2 phrases sont mal prononcés "which they collect, transform, by combining them with specific clean materials" et "to retrieve our results and spreadsheets"

Les phrases suivantes sont mal dites : "3.75 (three point seventy-five)" =} three pont seven five

Attention Ă  la prononciation de certains mots comme "theme", "installed", "healing", " affordable", "consumed","combining", "components", "various", "due to", "types", "Enzyme", "analysis", "microorganisms",

Il faut bien prononcer les "s" à la 3ème personne du singulier et après chaque mot au pluriel, exemple "a lot of manipulations (plutôt "a lot of testing )", "human**s_*

Sinon, c'est assez bien présenté et ton texte est bien écrit.

1.Introduction :

Theme selected:

The theme we have decided to address is honey. We chose this theme because hives have been installed in our school and we also know that honey has antiseptic, antibiotic, healing and antimicrobial properties. So honey was very affordable with all its properties, we knew that a lot of manipulations would be possible.

Its usefulness in society:

In our society, honey is first of all a nutrient-rich food consumed by humans, but also by bees, we use it mainly in alternative medicine.


Presentation of the honey: First of all, "honey is the natural sweet substance produced by bees from the nectar of plants or secretions from living parts of plants or excretions left on them by insects, which they collect, transform, by combining them with specific clean materials, deposit, dehydrate, store and leave to ripen in the combs of the hive".
Its water content varies from 17%, 20%. Honey is composed of different sugar contents. It contains 38% fructose, 31% glucose, just under 2% sucrose and about 7% maltose.
Nectar honeys are very acidic (pH between 3.5 and 4.5) and honeydew honeys are less acidic (pH above 4.5).
Honeydew is the substance excreted by aphids and scale insects that parasitize plants.
They suck up the sap from various trees and expel the excess sugars and water it contains through suck the anus. The bees then harvest this honeydew from the plants and transform it into honey.
The colour ranges from almost colourless to dark brown. As a result, each honey has its own « personality".

The labelling rules are:


-> the lists of ingredients,
-> the date of durability,
-> the name and address of the manufacturer or
-> the indication of the manufacturing batch,
-> the indication of the country of origin,
-> the contents of the components of the honey
and the various expressions that may be
indicated on a honey jar.
-> And includes the sales description.

Choice of the problem:
Does school honey have the same properties as conventional honey?

2.Assumptions made:

Hypotheses formulated :
-According to the various studies the antiseptic power comes from the high sugar content (glucose-fructose) and also from the enzymes.
→ Do these 2 types of honeys have the same honey content?

-Highlighting the antimicrobial power of the 2 types of honey:
→ Does one have an antimicrobial power more effective than the other ?
→ Do they keep the same antimicrobial properties at the end of 1 month, 2 months … if we
heat the honeys which of the 2 will be the most resistant to the temperature ?

3.Technological activities envisaged :
-> Antibiograms (showing antibacterial power): on the muller hinton agar medium with 3 different strains of bacteria (S.aureus, Pseudomonas, E.coli). Then repeat the same manipulation as the previous one but heating the honey.
-> Thin layer chromatography of sugars (check the absence of sucrose in the 2 honeys)
-> Enzyme kit (to determine the concentration of glucose, fructose and sucrose in honey).
-> Enumeration (to determine if the honeys contain small or large amounts of yeast).
-> pH-metry (determine the pH of the honeys which must be acidic (pH>7)).
-> Refractometer (refractometer analysis) to determine the water content
(not more than 20%).

4.Example of the manipulation: (pH-metry)
(determine the pH of the honeys which must be acidic (pH>7))
Make a 1/10th dilution, by weighing 10g of honey with a scale
(within the weighing range: 9.95<10g<10.05).
-> High School Honey: 9.9725g // All Flower Honey:9.9355g


In a 100ml volumetric flask add the weighed honey and distilled water. Then calibrate the pH meter with the buffer solutions (pH4/Ph7).
Transfer the contents of the volumetric flask to a beaker and add the magnetic rod so that the calibration of the honey can begin.
As the sodium hydroxide solution is poured into the beaker, the pH of the solution is measured using the pH meter. This is done by immersing the probe of the instrument in the diluted honey solution. The pH measurements will be taken from 1ml to 1ml.

Result of the experience presented above:

Graph 1:
pH=f(Vsol,NaOH) curve with determination of the
Ă©quivalent volume using the tangent method for
the determination of high school honey


High School Honey: pH=3,75
Veq = 10ml

Graph 2:
pH=f(Vsol,NaOH) curve with determination of the
Ă©quivalent volume by the tangent method for
the determination of multi-flower honey


All Flower Honey: pH=3,85
Veq = 7ml

Handling conclusion:
We could observe that the honeys studied had a pH between 3.5 and 4, which means that they are acidic. These results are consistent with the criteria of a nectar honey. Nectar honeys are very acidic, they have a pH between 3.5 and 4.5.

Results obtained from all protocols:
-Protocole 1 (Thin layer chromatography of sugars): The migration of sugars we to show the presence of glucose fructose and saccharose in honey.
-Protocole 2 (Refractometer): The water content obtained is 17%, which is included in the standard.
-Protocole 3 (Antibiograms): High school honey indicated antibacterial power against all three bacteria while commercial honey only against E.coli. High school honey therefore has stronger antibacterial power than commercial honey.
-Protocole 4 (Enumeration): High school honey had lower levels of microorganisms than commercial honey. Both honeys had a zero yeast count.
-Protocole 5 (Enzyme kit): As a result of the extended containment we were unable to retrieve our results and spreadsheets

results antibiograms:


result enumeration:


Blanket conclusion:


Overall, high school honey and commercial honey have similarities in their properties. Both honeys have an acidic pH which corresponds to a nectar honey. Both honeys have the same components in sugars, glucose, fructose and sucrose. Both honeys also have no yeast. However, there are some differences, high school honey shows a stronger antibacterial power and a lower germ content than commercial honey.

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