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“PRIMOŽ TRUBAR”
ELEMENTARY SCHOOL,
LAŠKO
Ivana ČAČIČ and Alja ŠPEC
FIELD: FOOD CHEMISTRY
Mentors: Marko JERAN, res. assoc....
BEES AND HONEYBees live in highly developed social
communities with 20.000 up to 80.000 members.
Among them are the queen ...
TYPES OF
HONEY
ACACIA HONEY
FLOWER HONEY
TILIA HONEY
CHESTNUT HONEY
SPRUCE HONEY
FOREST HONEY
SILVER FIR HONEY
CICADA HONEY
USE OF HONEY
ALTERNATIVE SWEETNER
CAN BE ADDED TO DRINKS
tea, lemonade, yoghurt, smoothies
IMPROVES DIGESTION
LOWERS CHOLE...
CHEMICAL COMPOSITION
• CARBOHYDRATES
• WATER
• AMINOACIDS
• ORGANIC COMPOUNDS
• MINERALS
• VITAMIS
• HYDROXYMETHYLFURFURAL...
EXISTING METHODS AND TEHNIQUES FOR
DETERMINATION OF COMPONENTS IN HONEY
REFRACTOMERY – water content in a sample
POLARIMET...
Many scientific studies have reported the beneficial effects of honey
and the confirmed the presence of components which h...
H Y P O T H E S I S
• Using simple chemical tests we can determine the main components in honey (e.g. sugars) and
to an ex...
SYNTHESIS OF ARTIFICIAL HONEY
FEHLING‘S TEST
TOLLENS‘ TEST
BIURET TEST
XANTHOPROTEIC REACTION
UV-VIS SPECTROSCOPY
SPECTROP...
RESULTS
AND
DISCUSSION
FEHLING‘S TEST RESULTS
Samples, which contained monosaccharides, were coloured
intensely yellow, some even intensely orang...
TOLLENS‘ TEST RESULTS
In synthetic honey from glucose and lactic acid under classic
heating conditions the amount of aldeh...
BIURET TEST RESULTS
Results of the biuret test for aminoacids confirmed our
expectations – most samples gave a negative re...
The xanthoproteic reaction for proteins gave a very slight
positive result for homemade and purchased honey samples.
The m...
RESULTS OF RECORDING UV/VIS SPECTRE IN SAMPLES OF HONEY
UV/VIS spectra were recorded in the
range from 200 nm to 500 nm.
W...
RESULTS OF QUANTITATIVE HMF
DETERMINATION WITH SPECTROPHOTOMETRY
Highest allowed
concentration of HMF is
40mg/kg!
Sample C...
C O N C L U S I O N
HYPOTHESIS CONFIRMED!
We were able to differentiate between different types of honey using
simple chemical tests.
The diff...
A
C
K
N
O
W
L
E
D
G
E
M
E
N
T
MENTORS:
Res. assoc. Marko JERAN, National Institute of Chemistry
dr. Eva MENART, National I...
THANK YOU
FOR
YOUR
ATTENTION!
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DETECTION OF PARAMETERS AND ACTIVE COMPONENTS IN HONEY, Alja Špec and Ivana Čačič #SciChallenge2017

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Our research work describes the properties of honey, which are the indicators of quality and possibly pollution of the environment, where the bees forage and therefore where the honey comes from. Absorption spectra of the analysed honey samples were decreasing from 200 to 700 nm, with a maximum between 250 and 280 nm. The results of quantitative hydroxylmethylfurfural (HMF) determination in natural honey samples were below the legal limit (40 mg/kg), higher values are commonly associated with elevated temperatures and light exposure. Treating the sample with microwaves causes a significant increase in the HMF concentration, which is consistent with the principles of microwave activation. Qualitative tests for specific components are a useful tool for determining the main components in honey and differentiating between natural and synthetic honey samples, and could be used as a basis for developing more accurate quantitative methods. #SciChallenge2017

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DETECTION OF PARAMETERS AND ACTIVE COMPONENTS IN HONEY, Alja Špec and Ivana Čačič #SciChallenge2017

  1. 1. “PRIMOŽ TRUBAR” ELEMENTARY SCHOOL, LAŠKO Ivana ČAČIČ and Alja ŠPEC FIELD: FOOD CHEMISTRY Mentors: Marko JERAN, res. assoc. National Institute of Chemistry dr. Eva MENART, univ. dipl. chem., National Institute of Chemistry National museum of Slovenia Co-mentor: Milena ŽOHAR, prof., Elem. school “Primož Trubarja Laško” Laško and Ljubljana, 2017 DETECTION OF PARAMETERS AND ACTIVE COMPONENTS IN HONEY
  2. 2. BEES AND HONEYBees live in highly developed social communities with 20.000 up to 80.000 members. Among them are the queen bee, a couple hundred drones, and the rest are non reproductive working bees. There are different types of honey, based on the geographical and botanical source of nectar, collection method and season. Throughout history honey has been used as a sweetener, in cosmetics, in varying ceremonies, for embalming bodies... Beekeeping is one of the oldest commercial activities. Originally, beekeeping took place in troughs, made from wood. Later hives as we know them today were built for this purpose. Beekeeping flourished in 18th and 19th century.
  3. 3. TYPES OF HONEY ACACIA HONEY FLOWER HONEY TILIA HONEY CHESTNUT HONEY SPRUCE HONEY FOREST HONEY SILVER FIR HONEY CICADA HONEY
  4. 4. USE OF HONEY ALTERNATIVE SWEETNER CAN BE ADDED TO DRINKS tea, lemonade, yoghurt, smoothies IMPROVES DIGESTION LOWERS CHOLESTEROL, IMPROVES BREATH EASES TOOTHACHE AND JOINT PAIN HAS CALMING EFFECT COSMETICS Balm, facial masks, baths, natural remedy for warts HEALING OF WOUNDS, BURNS, INFECTIONS, ACNE BALANCES WHITE AND RED BLOOD CELLS Nursing mothers and children of up to one year are discouraged from consuming honey, since it can contain a harmful bacteria Clostridium botulinum, which might be lethal for more sensitive groups of people.
  5. 5. CHEMICAL COMPOSITION • CARBOHYDRATES • WATER • AMINOACIDS • ORGANIC COMPOUNDS • MINERALS • VITAMIS • HYDROXYMETHYLFURFURAL (HMF) PHYSICAL PROPERTIES • DENSITY • VISCOSITY • HYGROSCOPY • ELECTRICAL CONDUCTIVITY • COLOUR • CRYSTALLIZATION • OPTICAL PROPERTIES HMF: • Potentially harmful • Forms during storage • Forms at elevated temperatures
  6. 6. EXISTING METHODS AND TEHNIQUES FOR DETERMINATION OF COMPONENTS IN HONEY REFRACTOMERY – water content in a sample POLARIMETRY – specific angle of rotation of linearly polarized light, passing through a sample HPAEC-PAD – presence of sugar (coupled chromatographic technique) pH-METRY – pH value, overall acids and lactones CONDUCTMETRY – electrical conductivity TXRF – elemental analysis, X-ray fluorescence with total reflection DRY COMBUSTION– ash content CHROMATOGRAPHIC TECHNIQUES (HPLC) – advanced technique for detailed analysis SPECTROPHOTOMETRY
  7. 7. Many scientific studies have reported the beneficial effects of honey and the confirmed the presence of components which have a positive effect on the human organism. More and more attention today is dedicated to the study of parameters, describing the quality of honey, but we often forget about components that can be formed over a longer period of time. From the consumer point of view it is important to maintain the honey‘s properties during storage. We suppose that over a longer period of time honey can form higher concentration of components, which can be unfavorable for humas in higher doses. One such example is hidroxymethylfurfural(HMF). In this research work we studied examples of real and model (synthetic) honey, and we believe our methods and results can also be used for raising awareness of the general public.
  8. 8. H Y P O T H E S I S • Using simple chemical tests we can determine the main components in honey (e.g. sugars) and to an extent differentiate between different types of honey. • With UV-Vis spectrometry we can see the difference between real and synthetic honey samples. • Different honey samples have different HMF contents, based on the conditions of storage and preparation (for synthetic honey samples, e.g. temperature and microwaves)
  9. 9. SYNTHESIS OF ARTIFICIAL HONEY FEHLING‘S TEST TOLLENS‘ TEST BIURET TEST XANTHOPROTEIC REACTION UV-VIS SPECTROSCOPY SPECTROPHOTOMETRIC DETERMINATION OF HMF A = log = ε × c × b oI I RCHO + 2 Cu2+ + 5 OH- → Cu2O + RCOO- + 3 H2O RCHO + 2 Ag(NH3)2 + + 3 OH- → RCOO- + 2 Ag + 4 NH3 + 2 H2O EXPERIMENTAL PART
  10. 10. RESULTS AND DISCUSSION
  11. 11. FEHLING‘S TEST RESULTS Samples, which contained monosaccharides, were coloured intensely yellow, some even intensely orange (e.g. purchased forest honey). The test was shown to be selective and results as expected, as disaccharides did not form the yellow colouring, indicative of a positive result.
  12. 12. TOLLENS‘ TEST RESULTS In synthetic honey from glucose and lactic acid under classic heating conditions the amount of aldehydes and ketones appears to be higher compared to most samples; the test result was a very obvious gray colour. The most intense colouring, which suggests the most aldehydes and ketones, was observed in homemade flower honey. Judging from the colour intensity, we can assume that the smallest amount of aldehydes and ketones was present in synthetic honey from sucrose and lactic acid under classic heating conditions. The test result in this case was a slight gray hue.
  13. 13. BIURET TEST RESULTS Results of the biuret test for aminoacids confirmed our expectations – most samples gave a negative result (no colour change). * We noticed a slight colour change in the samples of homemade and purchased honey. The result is justified, since this was natural honey. ** To reliably prove the presence of aminoacids in the samples, a different detection technique would be required – possibly quantitative and with a lower detection limit.
  14. 14. The xanthoproteic reaction for proteins gave a very slight positive result for homemade and purchased honey samples. The most colour change was observed in homemade mixed honey samples. As expected, no colour change was observed in samples of synthetic honey, which do not contain proteins. XANTHOPROTEIC REACTION RESULTS Real honey samples contain a mixture of mostly natural substances, which can chemically react and form complex products. Based on the results, the content of these substances seems very low.
  15. 15. RESULTS OF RECORDING UV/VIS SPECTRE IN SAMPLES OF HONEY UV/VIS spectra were recorded in the range from 200 nm to 500 nm. We observed differences mainly between real and synthetic honey samples.
  16. 16. RESULTS OF QUANTITATIVE HMF DETERMINATION WITH SPECTROPHOTOMETRY Highest allowed concentration of HMF is 40mg/kg! Sample Content of HMF [mg/kg] Purchased flower honey 27,08 Homemade flower honey 13,80 Purchased forest honey 24,19 Homemade mixed honey 27,95 Synthetic honey from surcose and lactic acid under microwaves 21,28 Synthetic honey from sucrose and lactic acid under conventional heating conditions 9,17 Synthetic honey from glucose and lactic acid under microwaves 11,57 Synthetic honey from glucose and lactic acid under conventional heating conditions 9,71 Synthetic honey from glucose and citric acid under conventional heating conditions 43,41 Synthetic honey from glucose and citric acid under microwaves 58,23
  17. 17. C O N C L U S I O N
  18. 18. HYPOTHESIS CONFIRMED! We were able to differentiate between different types of honey using simple chemical tests. The differences were well visible with UV-Vis spectrometry, particularly between real and synthetic honey samples. Analysed natural honey (purchased and homemade) did not exceed the critical value of HMF in honey based on legislation. Synthetic honey samples contained more HMF if they were prepared using microwaves. Relatively high and unsuitable amounts of HMF are linked to storage of honey – long exposure to light sources or high temperature. We can minimize the concentration of HMF in honey by storing it in dark, cool places.
  19. 19. A C K N O W L E D G E M E N T MENTORS: Res. assoc. Marko JERAN, National Institute of Chemistry dr. Eva MENART, National Institute of Chemistry National museum of Slovenia CO-MENTOR: Milena ŽOHAR, Elm. school Primož Trubar Laško Dr. Samo HOČEVAR, National Institute of Chemistry Asist. prof. dr. Katja ŽMITEK, Higher school for applied sciences Asist. prof dr. Igor PRAVST, Insitute for nutrition Mavrin GAŠPERŠIČ, BIC Ljubljana Jaka KRAŠEVEC, BIC Ljubljana Lidija TOPILIŠEK, Elm. school Primož Trubar Laško Marko SAJKO, Elm. school Primož Trubar Laško Pupils of “9. c” Our families Sincere gratitude to everyone who supported us and led us in the right direction (to fame and glory). Thank you once again!
  20. 20. THANK YOU FOR YOUR ATTENTION!

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