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Appréciation
Concernant la présentation orale.
La durée est beaucoup trop longue (7:06 mins au lieu de 5 mins).
Quelques erreurs à éviter comme : "it's possible to determinate =} determine, producted =} "produced, "The sugar contenant" =} content, "it correspondant =} it corresponds to the soluble dry matter" =} les derniers mots de cette phrase sont mal prononcés, "should appeared" =} "should appear, "the honey sample has a water percentage of less than 80% =} 18%, "which means that our honeys =} honey are slightly lacking in sugar content " =} les derniers mots de cette phrase sont mal prononcés
Attention Ă la prononciation de certains mots comme "our", "bees", "eating", ….
N'oublie pas de bien prononcer le morphème –ed : "decided", "installed, "envisage", "it's measure"", ….
Il faut bien prononcer les "s" Ă la 3ème personne du singulier et après chaque mot au pluriel, exemple "combs of the hive", "2 types", …..
Ta présentation est correcte mais il y a trop d'erreurs de prononciation. 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
seller,
-> 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?
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 ?
.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%).
Example of the manipulation:(REFRACTOMETER)
PRINCIPLE:
The refractometer makes it possible to determine the sugar content in a solution but also its water content. The sugar content is measured in Brix (°Be), it corresponds to the soluble dry matter. The water content is measured in percent (%).
PROTOCOL:
With the help of a pipette we took some honey.
Lift and fold the lid up and place a few drops (2 drops) of honey on the clean Flint prism and close the plastic lid. The rectangular area of the lid which has a sandblasted appearance should appear translucent, without air bubbles and without spilling over to the sides. Bring the refractometer close to a light source and read the Brix value corresponding to the white/blue colour change line.
RESULT :
We have tabulated the results.
| High School Honey | All flowers honey | |
| Moisture content (%) | 18 | 17.1 |
| Sugar content (°Be) | 42.5 | 43 |
We can see that the results are close between high school honey and commercial all-flower honey for water content and sugar content. If the honey sample has a water percentage of less than 18%, it will keep without any problem. Honey is in the standard because it is equal to 18%. The sugar content shows us that the two honeys have almost the same content. Honey should have a sugar content of 45 to 60°Be /100g we see that high school honey and conventional all-flower honey are below this, which means that our honeys are slightly lacking in sugar content but this does not influence its marketing.
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.
