Maillard reaction is the mother of all reactions ; Responsible for the characteristics thousands of flavours and appealing colour of majority of food products treated at high temperatures . There are different factors effecting rate of this reaction. Pool of flavours are produced here through a series of complex reactions .Imitating maillard reaction products has been a trending reasearch for scientists for meat flavours specially.

1. MAILLARD REACTION
Abhishek Badami 22PER201
1st Mtech Perfumery and Flavour
Technology

2. What is Maillard Reaction?
It is a series of reactions in which reducing sugar reacts
with amino acids at higher elevated temperature to
produce over 100 complex flavour, aroma compounds
and browning pigments called melonoidins.

3. History
• A French chemist, Louis Camille
Maillard, in 1912 first described
the maillard reaction.
• The complex reaction steps
which we study even today was
actually proposed by an
American chemist, John Hodge
as the ‘Hodge Scheme’ in 1953.

6. Early stage
• Condensation of an amino acid with reducing sugar to form N-
substituted glycosylamine.
• Rearrangement takes place to form more stable Amadori
compound.

7. Advanced stage
• The degradation of the Amadori and Heyns rearrangement
products occurs via three possible routes involving
deoxyosones, fission or Strecker degradation.
• Complex series of reactions including dehydration,
elimination, cyclization, fission and fragmentation result in a
pool of flavour intermediates and flavour compounds.

9. Final stage
• Colour development has been attributed to the final
stage of the maillard reaction.
• Condensation of carbonyls and amines forms brown
coloured high molecular weight compounds known
as Melonoidins.

10. Factors influencing the
maillard reaction
1. Heating time/temperature
2. Water activity
3. pH
4. System composition

11. • 2-acetyl-2-thiazoline had highest concentration after 10 min on heating at
100˚C and on longer heating time its concentration decreased.

12. • Maillard reaction takes place between water activity 0.3-0.9,
reaches maximum at intermediates 0.6-0.8
• However as the maillard reaction produces water, further
increase in water activity may inhibit maillard reaction.

13. • The maximum amount of popcorn odour 5-acetyl-3,4-dihydro-2H-1,4-
thiazine was observed at pH 7
• Less formed at pH 6-8
• Not at all formed below pH 5

14. System composition
• Quality and quantity of amino acids ≈ Extent of browning
• Lysine has two amino groups,it is most reactive that’s why
milk browns quickly.
• Cysteine is least coloured amino acid since it contains one
amino group and one sulphur group.
• Pentose > Hexose > Disaccahrides
• Cysteine†Ribose → Sulfur-containing meat flavor compounds
• Glucose†Lysine →Nitrogen-containing compounds (Pyrazines)

15. Maillard reaction products prominently seen
in
(1) Coffee and tea,
(2) Cocoa and chocolate,
(3) Bread and other cereal products,
(4) Peanuts, hazelnut and sesame seeds,
(5) Dairy
(6) Meat products.

16. Major classes of maillard reaction aroma
compounds
o Strecker aldehydes
o Pyrazines
o Pyridines
o Pyrroles
o Furans, furanones and pyranones
o Oxazoles

17. Maillard-derived compounds responsible for
aroma formation
1. Oxygen containing -furfurals, furanones, pyranones
2. Nitrogen containing-pyrazines, oxazoles and oxazolines,
pyrroles, pyrrolines
3. Sulfur containing-thiazoles and thiazolines, dithiazines,
furanthiols and sulfides.

19. Oxygen containing
• 2,3-butanedione (in stewed beef juice, boiled trout, French
fries)
• 2,3-pentadione (boiled trout and bread crust),
• Methylpropanal (cooked and roasted chicken, boiled beef,
French fries),
• Phenylacetaldehyde (peanuts and cocoa powder)

20. Nitrogen containing
• 2-ethyl-3,5-dimethylpyrazine (in roasted beef, cocoa powder,
French fries, coffee, nuts)
• 2,3-diethyl-5-methylpyrazine (peanuts, roasted beef, cocoa
powder, French fries, coffee)
• 2-acetyl-1-pyrroline (in cocoa powder, bread crust, popcorn)

21. Sulphur containing
• 2-furfurylthiol (stewed beef juice, roasted chicken, boiled
beef, coffee),
• 2-methyl-3-furan (cooked chicken, boiled beef)
• 3-mercapto-2-pentanone (cooked chicken, boiled beef)
• Methional (boiled trout, roasted beef,cooked chicken, French
fries, bread crust, coffee)

23. Strecker degradation
• Strecker degradation of amino acids by dicarbonyl compounds
is a vital associated reaction, during which an aldehyde and
aminoketone is formed due to the decarboxylation and
deamination .
• These aminoketones and aldehydes undergo an array of
reactions that lead to formation of important aroma
compounds.
• Aminoketones further gets condensed to form
dihydropyrazine and get oxidised to form pyrazines.

25. In Meat

26. In cocoa products

27. In milk

28. In cheese

29. Imitation of Meat flavours
Prolonged heating at higher temperatures leads to formation of typical meaty
flavours by
• Maillard reaction
• Lipid oxidation
• Interaction between maillard reaction Products with lipid-oxidized products
• Thiamin degradation

30. Production of Chicken Flavour
Raw materials required
1. Amino acid source
2. Reducing sugar source
3. Fatty acid/ fat
4. Solvent (water)
5. pH regulator
Miscellaneous compounds
1. Salt
2. Preservatives
3. Thickners emulsifiers
4. Flavourants , colourants
5. Free flowing agent
Processing conditions
1. Temperature≦ 180°
2. Time=1∕4 hour
3. pH ≦8

31. How does maillard reaction products influence
texture of food?
The possible ways how Maillard reaction products effects on
texture are:
(a) Protein crosslinking formation,
(b) Emulsions properties
(c) Protein–polysaccharides conjugates formation.

32. Negative aspects
• Off flavour development
• Flavour loss
• Discolouration
• Loss of nutrients
• Carcinogens-Acrylamide

33. References
• https://www.researchgate.net/publication/272962881_Food_Processing_
and_Maillard_Reaction_Products_Effect_on_Human_Health_and_Nutritio
n#:~:text=Maillard%20reaction%20produces%20flavour%20and,in%20the
%20absence%20of%20enzyme.
• https://www.frontiersin.org/articles/10.3389/fnut.2022.973677/full
• https://www.researchgate.net/publication/359209270_Maillard_Brownin
g_Pros_and_Cons_in_Dairy_and_Food_Industries
• https://www.researchgate.net/publication/331968323_Maillard_Reaction
_and_Effect_of_Various_Factor_on_the_Formation_of_Maillard_Products
_and_Its_Impact_on_Processed_Food_Products
• https://www.intechopen.com/chapters/37707
• The maillard reaction in foods and medicine by John O’Brein
• Maillard reactions in chemistry,food and health by T.P. Labuza

34. Thank
you