1. OFF FLAVOR FORMATION IN FOODSTUFFS
OBJECTIVES
1. Formation of aroma compounds via enzymatic mechanism;
2. Transformation of carbohydrates, lipids and amino acids;
3. Transformation of other compounds.

2. OFF FLAVOR FORMATION IN FOODSTUFFS1
Off-flavor – a flavor that is not natural or up
to standard owing to deterioration or contamination

3. OFF FLAVOR FORMATION IN FOODSTUFFS2
Off-flavor

4. OFF FLAVOR FORMATION IN FOODSTUFFS4
Off-flavor
1. As a result of chemical and biochemical processes
1.1. Fishy / mushroom smell in butter (octa-1-en-3-on) –
degradation of phospholipids; otherwise – smell of mushrooms, found
in Camembert cheese

5. OFF FLAVOR FORMATION IN FOODSTUFFS5
Off-flavor
1. As a result of chemical and biochemical processes
1.2. Soybean oil – presence of 3-methyl-2,4-nonadion and diacetyl:
bean and oily aroma;
1.3. In the dry sterilized milk – sometimes is felt pockety and stale smell; the reason is oxidation of lipids and formation of Z-nona-6-enal; Other reason might be presence of о-amino acetophenone – potato and animal odor
(interestingly at higher concentrations this compound have grape odor notes!)
The main factor for
formation of smell of
molds and stale – cork
taint.
2,4,6-trichloroanisole (TCA)

6. OFF FLAVOR FORMATION IN FOODSTUFFS6
Off-flavor
1. As a result of chemical and biochemical processes
1.3. Off-flavor formation during carrot treatment – sterilized or dried; reason – formation of ionones (α-, β-) having floral aroma

7. OFF FLAVOR FORMATION IN FOODSTUFFS 7
Off-flavor – due to degradation of carotenoids

8. OFF FLAVOR FORMATION IN FOODSTUFFS8
Off-flavor
1. As a result of chemical and biochemical processes
oxidative
deamination
Skatole
Smell in the Emmental
Off-flavor in processed
peppers
Tryptophan
decarboxylation
It’s formed in the mammalian digestive
tract – in higher concentrations has
strong fecal odor. In low concentrations
has flowery smell (found in some flowers,
used as fragrance and fixative in perfumes.
о-aminoacetophenon
(animal, potato smell);
Found in tortilla, taco
(in dairy products –
gives off-flavor)

9. OFF FLAVOR FORMATION IN FOODSTUFFS9
Off-flavor
2. As a results from external contamination of foodstuffs
2.1. Geosmin in water, vegetables (beets) and fishes – smell of soil, earth
produced by gram-positive bacteria Streptomyces.
2.2. Formation of acrid taste and burnt smell in dairy products – from the milk of animals consumed Coronopus
didymus (swinecress); reason – formation of benzylmethyl sulfide and benzylthiocyanate; losses for the producers.
Coronopus didymus (swinecress)

10. OFF FLAVOR FORMATION IN FOODSTUFFS10
Off-flavor
2. As a results from external contamination of foodstuffs
2.3. Allium ursinum – known as ramsons,
 buckrams, wild garlic; Animals which has consumed it
gives milk with garlic off-flavor.