1. Caramel is produced through carefully controlled heating of foods like sugars and starches. This causes chemical reactions that result in a dark brown liquid or solid used as a food coloring. 2. The caramelization process occurs in stages as the temperature increases, producing compounds that determine the caramel's color and flavor. Sugars like glucose and fructose undergo reactions to form substances like furans and hydroxymethylfurfural. 3. Caramel is mainly used as a food additive to color processed foods and beverages. There are different types of caramel classified based on production method and properties like color and stability in various substances. Caramel can interact with other foods and its production is related to the

1. OBJECTIVES
1. Types of caramel produced;
2. Mechanism and major chemical reactions;
3. Caramel usage.
CARAMELIZATION

2. 1
1. Significance – about 11% of all colorants used; around 200 000 tons annual
consumption
1850г. – used for the first time in Europe commercially
According to the FDA, “The color additive caramel is the dark-brown liquid or
solid material resulting from the carefully controlled heat treatment of the
following food-grade carbohydrates: dextrose, invert sugar, lactose, malt syrup,
molasses, starch hydrolysates and fractions thereof, sucrose.”36
According to JECFA (The Joint FAO/WHO Expert Committee on Food Additives),
“Caramel is a complex mixture of compounds, some of which are in the form of
colloidal aggregates, manufactured by heating carbohydrates either alone or in
the presence of food-grade acids, alkalis or salts; classified according to the
reactant used.” 41
36. U.S. Food & Drug Administration, Summary of Color Additives Listed for Use in the
United States in Food, Drugs, Cosmetics and Medical Devices, Washington, D.C.,
1999.
41. JECFA, Combined compendium of food additive specifications, http://www.fao.org.
CARAMELIZATION

3. 2
CARAMELIZATION
!

4. 3
2. Obtaining; phases
Raw materials – glucose, glucose-fructose syrup (HFCS), sugar,
hydrolysates – corn, wheat, tapioca etc.
Chemical reactions involved – hydrolysis, enolization, dehydration, bonds (С-С)
rupture, aldolization, cyclization, radical reactions
Requirements
Hue index – 3.5-7.5
CARAMELIZATION
Hue index = 10 log (A510 / A610)
Sugar Temperature
Fructose 110° C
Galactose 160° C
Glucose 160° C
Maltose 180° C
Saccharose 160° C
Initial caramelization temperatures of common carbohydrates

5. 4
I stage – anhydro sugars formation – 30 min (150-170ºС), 4.5% losses;
dimerization – isosachrosan formation;
II stage – formation of caramelan – 50 min (180ºС), 9% losses
Soluble in water and EtOH; bitter taste; tm = 138ºС
III stage – formation of caramelen – 80 min (180ºС), 14% losses
Soluble in water; bitter-sweet taste; tm = 154ºС
IV stage – formation of caramelin (huminic type polymers) – 110 min (180ºС),
Slightly soluble in water; average composition С125Н188О80
CARAMELIZATION
2. Obtaining; phases
!

6. 5
Step T, °C / 60 min Description and use Image
1 Evaporation
of water
100 Sugar is melted and impurities rise to the
surface;
2 Small
Thread
102 No colour; soft cooling; no flavour change.
Used in frostings.
3 Large
Thread
104 No colour; soft cooling; no flavour change.
Used in preserves.
4 Small Ball 110 - 115 No colour; semi-soft cooling; no flavour
change. Used in cream candy fillings,
Italian meringue, fondants, fudge, and
marshmallows;
5 Large Ball 119 - 122 No colour; firm cooling; no flavour change.
Used in soft caramels;
6 Light Crack 129 No colour; firm cooling; no flavour change.
Used in semi-hard candies.
7 Hard Crack 165 - 166 Pale colour; hard cooling; no flavour
change. Used in butterscotch and hard
candies;
CARAMELIZATION
2. Obtaining; phases – caramelization of sucrose

7. 6
8 Extra-hard
Crack
168 Slight colour; shatters like glass during
cooling; no flavour change. Used in hard
candies;
9 Light
Carmel
180 Pale amber to golden brown; rich flavour.
10 Medium
Carmel
180 - 188 Golden brown to chestnut brown; rich
flavour;
11 Dark
Carmel
188 - 204 Very dark and bitter; smells burned. Used
for colouring, but lack of appropriate
sweetness;
12 Black Jack 210 Also known as "monkey's blood." At this
point, the sugar begins to breaks down to
pure carbon. Burning flavour.
CARAMELIZATION
2. Obtaining; phases – caramelization of sucrose

8. 7
electronegative caramel (рН 1.5-3.0) – obtained in acid medium, use of
inorganic catalysts, 160ºС;
electropositive caramel (рН 4.0-5.0) – obtained in presence of ammonia,
120-130ºС.
2.1. Obtaining of anhydro-sugars
CARAMELIZATION
2. Obtaining; phases
D-glucopyranose
- H2O
D-glucosan
to
O
H
HO
H
HO
H
OH
OH
H
H
OH
O
H
HO
H
HO
H
O
H
H
OH
D-glucopyranose
- H2O
to
O
H
HO
H
HO
H
H
OH
H
OH
OH
O
H
HO
H
HO
H
H
OH
H
O
D-glucosan

9. 8
CARAMELIZATION
2.1. Obtaining of anhydro sugars
2. Obtaining; stages

10. 9
2.2. Obtaining of heterocyclic unsaturated compounds
CARAMELIZATION
2. Obtaining; stages
5-methyl-2-(1-propenyl)-
furan
furfuryl
alcohol
α-angelica
lactone
5-methyl-2-
furanone
2-methyl-
tetrahydro-3-
furanone
2-furfural 5-methyl-
2-furfural
2-acetylfuran 2-propionyl-
furan
isomaltol 2-(2-hydroxy-
acetyl)-furan
5-HMF 2,5-diformyl furan

11. 10
CARAMELIZATION
2. Obtaining; stages
2.2. Obtaining of heterocyclic unsaturated compounds
5-methyl-2-
furylic acid
2-(2-oxo-
propionyl)furan
furfurylacetate 5-hydroxymethyl
2-furilic acid
5-methyl-2-(2-oxo-
propionyl)-furan
1-(2-furyl)-1,2-
pentandion
5-(formyloximethtyl)-
2-furfural
5-(acetoxymethyl)-
2-furfural
furaneol formoin

12. 11
CARAMELIZATION
2. Obtaining; stages
2.2. Obtaining of heterocyclic unsaturated compounds
cyclotene Maltol E636
Flavor enhancer
5-hydroxymaltol
5-hydroxy-5,6-
dihydromaltol
5-(2-furfuryl)-
2-furfural
5-(5-methyl-2-furfuryl)-
2-furfural 2,2’-difurilketon
difurfurylether bis-(5-formyl-2-furfuryl)-ether

13. 12
Some flavors present in the caramels
diacetyl (buttery flavor);
esters, lactones – rum flavor, sweetish
furans – roasted nuts flavor
maltol and isomaltol – caramel-like, sweetish, burnt (well-done)
CARAMELIZATION
2. Obtaining; stages

14. 13
- 4-methylimidazole (4-MeI) - Neurotoxic effects
- 2-acetyl-4(5)-tetrahydroxybutylimidazole (THI)
Immunosuppressive effects
CARAMELIZATION
2. Obtaining; stages
2.3. Obtaining of unwanted heterocyclic unsaturated compounds
2.4. Polymerization – aldol condensation reactions
N
N
H
N
N
H
O
OH
OH
OH
OH

15. 14
3. Application – mainly as food additive
CARAMELIZATION
Parameter
Type I (E
150a)
Type II (E
150b)
Type III (E
150c)
Type IV (E
150d)
Sulfites no yes no yes
Ammonia
compounds
allowed
no no yes yes
Catalysts NaOH Na2SO3 NH3 (NH4)SO3
Charge - negative positive negative
Stability in:
- Alcohol
- Tannins
- Acids
+
-
-
+
+
-
-
-
+
-
+
+
Hue no Yellow-orange no Brown
Application
Alcoholic
beverages,
coffee extracts
Aperitives and
digestives,
aroma extracts
Beer, vinegar,
sauces
Fizzy drinks,
some foods
!

16. 15
CARAMELIZATION
3. Application – mainly as food additive

17. 16
3. Obtaining
CARAMELIZATION

18. 17
Interactions with other substances
Over 700ppm – could lead to aspartame hydrolysis.
Adulteration of juices, coffee, honey.
Caramelization could be regarded as part of the Maillard reaction and as
separate reaction.
CARAMELIZATION
Info - http://www.food-info.net/uk/colour/caramel.htm