Table 2 Changes in volatile compounds as a function of cysteine

Furans

179.9 ± 7.21

36.62 ± 2.54

13.39 ± 1.25

15.40 ± 1.03

8.13 ± 0.92

1

534–22-5

2-Methylfuran

ND

13.50 ± 1.21^a

ND

ND

ND

ND

Chocolate, coffee, nut

2

98–01-1

Furfural-M

ND

121.7 ± 10.2^a

32.33 ± 2.8^b

9.54 ± 0.83^c

10.94 ± 0.24^c

3.30 ± 0.12^c

Almond

3

1192–62-7

2-Acetylfuran

ND

3.70 ± 0.28^b

2.89 ± 0.53^d

3.55 ± 0.12^c

4.46 ± 0.41^a

3.37 ± 0.22^c

Almond, nutty, milk,

4

3194–15-8

1-Propanone,1-(2-furanyl)-

ND

2.80 ± 0.11^a

0.72 ± 0.31^b

0.3 ± 0.05^c

ND

ND

Sulfurous

5

13679–41-9

3-Phenylfuran

ND

2.31 ± 0.16^a

0.67 ± 0.07^b

ND

ND

ND

6

19377–82-3

2-Furanmethanamine,N-(2-furanylmethylene)-

ND

35.89 ± 2.42^a

ND

ND

ND

ND

7

3777–69-3

2-Amylfuran

ND

ND

ND

ND

ND

1.45 ± 0.23^a

Grass

Sulfur-containing compound

ND

17.34 ± 1.25

25.05 ± 2.46

62.27 ± 5.31

298.50 ± 21.43

190.14 ± 11.34

8

624–92-0

Dimethyl disulfide

ND

5.56 ± 0.2^a

ND

ND

ND

ND

Sulfurous, vegetable, onion

9

3658–80-8

Dimethyl trisulfide

ND

1.94 ± 0.1^a

ND

ND

ND

ND

Sulfurous, cooked onion, meaty

10

3268–49-3

3-(Methylthio) propionaldehyde

ND

8.81 ± 0.67^b

12.09 ± 0.7^a

4.34 ± 0.13^c

1.59 ± 0.04^d

1.55 ± 0.03^d

Meaty, cooked onion, seafood

11

24295–03-2

2-Acetylthiazole

ND

1.03 ± 0.02^b

3.26 ± 0.12^b

14.35 ± 0.78^a

1.36 ± 0.06^ab

1.26 ± 0.05^b

Beef, nutty, popcorn, roasted peanuts

12

28588–74-1

2-Methyl-3-furanthiol

ND

ND

4.31 ± 0.25^d

18.16 ± 1.23^c

43.73 ± 3.52^b

55.35 ± 3.87^a

Meaty

13

932–95-6

2,5-Thiophenedicarboxaldehyde

ND

ND

3.98 ± 0.14^d

16.79 ± 0.98^b

32.23 ± 2.81^a

14.87 ± 0.84^c

14

57500–00-2

Methyl furfuryl disulfide

ND

ND

1.41 ± 0.08^b

2.21 ± 0.22^a

ND

ND

Sulfury, coffee, roasted alliaceous, meaty

15

5834–16-2

3-Methyl-2-thiophene carboxaldehyde

ND

ND

ND

6.16 ± 0.73^b

8.67 ± 0.35^a

5.52 ± 0.43^c

16

98–03-3

2-Thenaldehyde

ND

ND

ND

0.26 ± 0.03^b

1.14 ± 0.05^a

ND

Bitter almonds

17

98–02-2

Furfuryl mercaptan

ND

ND

ND

ND

209.8 ± 12.41^a

111.6 ± 8.3^b

Sulfury, roasted, coffee, fatty

18

1639–04-9

2-Methyl-3-pentanethiol

ND

ND

ND

ND

1.24 ± 0.15^a

ND

19

554–14-3

2-Methylthiophene

ND

ND

ND

ND

ND

4.87 ± 0.28^a

Sulfurous, alliaceous onion, green

Nitrogen-containing compounds

3.1 ± 0.21

1119.0 ± 32.83

351.00 ± 18.76

314.99 ± 23.85

49.14 ± 2.96

40.60 ± 3.98

20

290–37-9

Pyrazine

ND

ND

3.93 ± 0.29^a

ND

ND

ND

Sweet corn

21

5910–89-4

2,3-Dimethyl pyrazine

ND

0.69 ± 0.16^a

ND

ND

ND

ND

Nutty, peanut, coffee, walnut caramel

22

14667–55-1

2,3,5-Trimethyl Pyrazine

ND

47.62 ± 2.17^a

ND

ND

ND

ND

Nutty, potato, roasted peanut

23

13360–65-1

3-Ethyl-2,5-dimethyl- Pyrazine

ND

34.22 ± 2.29^a

ND

ND

ND

ND

Potato, cocoa, roasted nutty

24

91010–41-2

2-Methyl-6-(3-methyl-butyl)-pyrazine

ND

1.33 ± 0.32^a

ND

ND

ND

ND

25

56617–70-0

3,5-Dimethyl-2-(2-methylbutyl)- (9CI) pyrazine

ND

10.22 ± 1.37^a

ND

ND

ND

ND

26

18433–98-2

2,5-Dimethyl-3-(3-methylbutyl)- Pyrazine

ND

104.3 ± 5.6^a

21.77 ± 1.86^b

ND

ND

ND

Fruity

27

18138–03-9

2-Propylpyrazine

ND

ND

17.51 ± 1.25^a

6.85 ± 0.53^b

ND

ND

Nutty

28

29460–92-2

2-(2-Methylpropyl)-pyrazine

ND

ND

1.10 ± 0.33^b

4.33 ± 0.15^a

4.45 ± 0.47^a

1.13 ± 0.23^b

29

13925–07-0

2-Ethyl-3,5-dimethyl- Pyrazine

ND

ND

6.57 ± 0.26^a

2.38 ± 0.37^b

ND

ND

Almonds, roasted nuts, coffee

30

29461–03-8

2-Methyl-5-propyl-pyrazine

ND

ND

ND

ND

ND

5.46 ± 0.48^a

31

109–08-0

2-Methyl pyrazine

ND

54.86 ± 3.64^c

78.98 ± 5.43^b

88.70 ± 9.25^a

44.69 ± 3.92^d

32.75 ± 2.43^e

Nutty, cocoa, chocolate, peanut

32

123–32-0

2,5-Dimethyl pyrazine

3.1 ± 0.43^d

851.9 ± 24.32^a

216.1 ± 13.52^b

202.1 ± 15.26^c

ND

ND

Cocoa, roasted nuts, roast beef

33

1438–94-4

1-Furfurylpyrrole

ND

6.99 ± 0.45^a

ND

ND

ND

ND

Green, fruity, coffee, vegetable

34

616–43-3

3-Methyl-1H-pyrrole

ND

ND

ND

ND

ND

1.26 ± 0.05^a

35

274–40-8

Indolizine

ND

ND

5.09 ± 0.67^a

3.13 ± 0.26^b

ND

ND

36

289–95-2

Pyrimidine

ND

6.87 ± 0.53^a

ND

7.22 ± 0.83^a

ND

ND

37

16975–71-6

2-Ethenyl-1-methylimidazole

ND

ND

ND

0.27 ± 0.03^a

ND

ND

The oxygen-containing compounds

Aldehydes

211 ± 14.68

136.43 ± 10.52

218.13 ± 14.89

275.40 ± 21.47

421.63 ± 32.58

280.11 ± 23.24

38

110–62-3

Valeraldehyde

1.46 ± 0.45^a

ND

ND

ND

ND

ND

39

1860–39-5

5-Methylhexanal

3.03 ± 0.24^a

ND

ND

ND

2.54 ± 0.12^b

ND

40

66–25-1

Hexanal

13.56 ± 2.11^b

7.60 ± 0.52^d

8.44 ± 0.65^d

11.83 ± 1.58^c

15.44 ± 1.26^a

12.55 ± 1.32^c

Green, fatty, grass, fruity sweaty

41

111–71-7

Heptaldehyde

8.11 ± 0.65^a

4.25 ± 0.34^c

5.12 ± 0.59^b

5.86 ± 0.42^b

8.78 ± 0.64^a

7.71 ± 0.84^a

Fruity

42

57266–86-1

2-Heptenal, (2Z)-

2.39 ± 0.13^a

ND

ND

ND

ND

2.12 ± 0.19^a

43

100–52-7

Benzaldehyde

32.04 ± 3.42^d

27.30 ± 1.42^e

69.80 ± 5.23^c

108.1 ± 9.75^b

138.0 ± 12.3^a

70.15 ± 6.75^c

Bitter almond, cherry

44

4313–03-5

2,4-Heptadienal, (E,E)-

8.78 ± 0.62^a

ND

ND

ND

6.13 ± 0.39^b

4.44 ± 0.22^c

Fatty, vegetable

45

124–13-0

Octanal

6.56 ± 0.34^d

ND

ND

9.76 ± 0.45^b

11.36 ± 1.36^a

7.96 ± 0.81^c

Orange, fatty

46

122–78-1

Benzeneacetaldehyde

5.35 ± 0.67^d

13.49 ± 0.95^a

12.21 ± 0.78^ab

11.26 ± 1.33^b

7.12 ± 0.84^c

4.94 ± 0.23^d

Rose, fruity

47

2548–87-0

(E)-2-Octenal

4.19 ± 0.44 ^b

ND

ND

ND

ND

6.44 ± 0.73^a

Fresh cucumber, fatty, banana

48

124–19-6

Nonanal

48.10 ± 3.56^c

24.33 ± 1.76^e

37.44 ± 1.75^d

51.35 ± 4.58^c

96.64 ± 10.41^a

75.29 ± 6.54^b

Rose, fatty

49

112–31-2

Decanal

10.04 ± 1.24^d

6.33 ± 0.34^e

10.76 ± 0.89^d

14.23 ± 1.25^c

18.15 ± 1.64^b

23.11 ± 3.21^a

fatty, fruit

50

15764–16-6

2,4-Dimethylbenzaldehyde

5.70 ± 0.64^a

ND

ND

ND

ND

ND

Bitter almond, sweet

51

2497–25-8

(Z)-2-Decen-1-al

9.32 ± 1.27^a

3.37 ± 0.23^c

2.64 ± 0.18^d

3.64 ± 0.27^c

5.71 ± 0.48^b

5.37 ± 0.46^b

Butter almond

52

28785–06-0

Benzaldehyde, 4-propyl-

19.79 ± 1.65^a

13.75 ± 1.54^c

16.53 ± 1.48^b

ND

ND

ND

53

112–44-7

Undecanal

3.92 ± 0.26^b

ND

3.34 ± 0.45^b

2.54 ± 0.16^c

4.57 ± 0.22^a

4.41 ± 0.50^a

Fruity, rose, flower,

54

25152–84-5

(E,E)-2,4-Decadienal

9.92 ± 1.01^a

ND

ND

ND

ND

ND

Cucumber, citrus, nutty

55

2463–77-6

Undecenal

15.72 ± 1.29^a

4.33 ± 0.39^c

4.84 ± 0.26^c

3.53 ± 0.16^d

7.15 ± 0.54^b

7.02 ± 0.62^b

Grass, fatty, citrus

56

112–54-9

Dodecyl aldehyde

3.94 ± 0.08^c

ND

ND

2.83 ± 0.13^d

5.02 ± 0.39^a

4.39 ± 0.23^b

Soapy, aldehydic, green floral

57

590–86-3

3-Methylbutyraldehyde

ND

5.27 ± 0.36^a

4.15 ± 0.14^b

2.99 ± 0.31^c

ND

ND

58

2548–87-0

(E)-2-Octenal

ND

0.40 ± 0.12^d

0.61 ± 0.03^c

0.82 ± 0.04^b

2.32 ± 0.18^a

ND

Meaty, fatty, chicken

59

56599–95-2

2-Bromo octadecanal

ND

3.52 ± 0.21^d

10.44 ± 0.92^c

4.79 ± 0.26^d

17.09 ± 0.95^b

44.21 ± 1.58^a

60

21662–16-8

(E,E)-2,4-Dodecadienal

ND

3.42 ± 0.24^b

0.86 ± 0.04^c

0.83 ± 0.06^c

6.70 ± 0.03^a

ND

61

638–66-4

Octadecanal

ND

19.08 ± 1.28^d

30.96 ± 3.67^c

41.04 ± 3.95^b

68.95 ± 5.83^a

ND

Alcohols

14.36 ± 1.20

10.02 ± 1.07

6.32 ± 0.52

5.02 ± 0.43

30.63 ± 0.29

19.13 ± 1.12

62

89182–08-1

1-Cyclobutene-1-methanol

5.40 ± 0.24^a

1.16 ± 0.08^c

ND

1.81 ± 0.11^b

ND

ND

63

4706–89-2

2-Tetradecanol

1.42 ± 0.13^a

ND

ND

ND

ND

ND

64

2490–48-4

1-Hexadecanol,2-methyl-

7.53 ± 0.34^a

3.30 ± 0.24^b

2.01 ± 0.12^c

1.07 ± 0.08^e

3.68 ± 0.26^b

1.66 ± 0.09^d

65

111–28-4

2,4-Hexadien-1-ol

ND

ND

4.31 ± 0.32^a

2.14 ± 0.15^c

1.96 ± 0.15^c

2.53 ± 0.18^b

66

6261–22-9

2-Pentyn-1-ol

ND

ND

ND

ND

3.61 ± 0.28^a

ND

67

6712–79-4

Isopinocarveol

ND

ND

ND

ND

8.25 ± 0.69

10.07 ± 1.25

68

694–29-1

cis-1-Cyclopentene-3,4-diol

ND

ND

ND

ND

13.12 ± 1.84^a

ND

69

56554–77-9

13-Heptadecyn-1-ol

ND

ND

ND

ND

ND

4.86 ± 0.35^a

Ketones

ND

16.59 ± 3.04

18.64 ± 2.36

35.59 ± 3.29

61.51 ± 7.35

73.25 ± 5.42

70

51004–21-8

2-Butanone,4-cyclopentylidene-

ND

1.50 ± 0.09^a

ND

ND

ND

ND

71

3796–70-1

Geranylacetone

ND

3.52 ± 0.26^d

4.84 ± 0.32^c

6.42 ± 0.49^b

10.42 ± 1.04^a

4.80 ± 0.33^c

Grass, rose

72

111–13-7

2-Octanone

ND

1.99 ± 0.12^c

2.76 ± 0.26^a

2.41 ± 0.22^b

2.93 ± 0.03^a

2.49 ± 0.10^b

Apple, grass, floral

73

116–09-6

Hydroxyacetone

ND

9.59 ± 1.01^b

9.80 ± 2.30^b

17.79 ± 2.54^a

ND

ND

74

110–43-0

2-Heptanone

ND

ND

1.24 ± 0.05^d

1.56 ± 0.1^c

2.45 ± 0.02^b

3.48 ± 0.23^a

Fruity, coconut, woody

75

13125–74-1

5,9-Dodecadien-1-one,6,10-dimethyl-,(E,E))-

ND

ND

ND

4.68 ± 0.23^b

5.24 ± 0.45^a

4.38 ± 0.52^b

76

24653–75-6

2-Propanone,1-mercapto- (8CI,9CI)

ND

ND

ND

2.01 ± 0.28^c

10.94 ± 1.95^b

14.28 ± 1.65^a

77

21856–89-3

6-Hydroxyhexan-2-one

ND

ND

ND

0.73 ± 0.02^a

ND

ND

78

67–64-1

Acetone

ND

ND

ND

ND

29.53 ± 3.01^b

36.35 ± 3.57^a

Apple, pear

79

107–87-9

2-Pentanone

ND

ND

ND

ND

ND

7.48 ± 0.44^a

Fruity

Esters

2.72 ± 0.14

2.84 ± 0.16

ND

ND

ND

4.46 ± 0.25

80

623–42-7

Methyl butyrate

2.72 ± 0.14^b

1.47 ± 0.05^b

ND

ND

ND

4.46 ± 0.25^a

Fruity, apple, banana

81

5331–43-1

Carbobenzoxyhydrazide

ND

1.37 ± 0.07^a

ND

ND

ND

ND

Acids

ND

33.25 ± 4.23

55.38 ± 4.68

30.72 ± 3.28

39.28 ± 2.37

1.05 ± 0.01

82

64–19-7

Acetic acid glacial

ND

33.25 ± 4.23^a

22.74 ± 2.36^b

18.73 ± 2.1^c

ND

ND

Sharp pungent sour vinegar

83

57–10-3

Palmitic acid

ND

ND

32.64 ± 2.84^b

12.00 ± 0.87^c

39.28 ± 3.16^a

ND

84

2091–29-4

9-Hexadecenoic acid

ND

ND

ND

ND

ND

1.05 ± 0.09^a

Phenol

25.76 ± 1.63

7.06 ± 0.64

9.93 ± 0.88

8.72 ± 0.24

18.77 ± 0.85

18.78 ± 1.21

85

6712–79-4

Isopinocarveol

1.71 ± 0.12^a

ND

ND

ND

ND

ND

86

96–76-4

2,4-Di-tert-butylphenol

3.98 ± 0.43^d

7.06 ± 0.82^b

5.90 ± 0.66^c

4.72 ± 0.13^d

13.67 ± 0.22^a

14.17 ± 0.11^a

87

128–37-0

Butylated hydroxytoluene

20.07 ± 2.24^a

ND

4.03 ± 0.29^b

4.00 ± 0.16^b

ND

ND

88

497–39-2

4,6-Di-tert-butyl-m-cresol

ND

ND

ND

ND

3.45 ± 0.42^b

4.60 ± 0.53^a