Table 15.
Odour-active compounds identified in pea (Pisum sativum L.) and lupin (Lupinus angustifolius L.).
| Chemical Classes | Volatiles | CAS | Origin (s) | Odour Threshold | Odour Descriptors | Pea | Lupin | ||
|---|---|---|---|---|---|---|---|---|---|
| Dehulled 1 (DM) | Protein Isolate 1 (DM) | Whole 2 | Dehulled 3 | ||||||
| Aldehydes | 4-Ethylbenzaldehyde | 53951-50-1 | 13 ppb 5 | Sweet, honey, hay, dry vegetable (pea isolate) | (ND) | %D 83 (1.7 µg/g) | |||
| Phenylacetaldehyde | 122-78-1 | AA | 4 ppb 5 | Floral (pea isolate) | (ND) | %D 56 (2.1 µg/g) | |||
| Vanillin | 121-33-5 | N 6 | 53 µg/L (water) 4 | Sweet, vanilla, caramel (peas, dehulled lupin) | %D 33 (0.1 µg/g) | %D 28 (0.3 µg/g) | FD 1024 | ||
| Ethylvanillin | 121-32-4 | N 6 | 100 ppb 5 | Vanilla (dehulled lupin) | FD 256 | ||||
| 3-Methylthiopropanal | 3268-49-3 | AA | 0.1 % (oil) 5 | Potato (pea isolate) | (ND) | %D 94 (0.1 µg/g) | |||
| Hexanal | 66-25-1 | FFA | 2.4 µg/L (water) 4 | Grass, floral, fruity (dehulled pea)/Fresh grass (pea isolate)/Fresh green bean, green (whole lupin) | %D 50 (0.6 µg/g) | %D 61 (83.0 µg/g) | OI 10 (135 µg/g) | ||
| Heptanal | 111-87-7 | FFA | Green vegetable (pea isolate) | (ND) | %D 28 (16.2 µg/g) | (NO–4 µg/g) | |||
| Octanal | 124-13-0 | FFA | 3.4 µg/L (water) 4 | Floral, sweet, beany (whole lupin) | OI 26 (3 µg/g) | ||||
| (E)-2-Octenal | 2548-87-0 | FFA | 3–6 ppb 5 | Pea, dry vegetable (pea isolate)/Fatty, green, cucumber (dehulled lupin) | (ND) | %D 94 (0.3 µg/g) | OI 98 (3 µg/g) | ||
| Nonanal | 124-19-6 | FFA | 2.8 µg/L (water) 4 | Solvent (dehulled pea) | %D 17 (0.9 µg/g) | (NO–9.5 µg/g) | |||
| (E)-2-Nonenal | 18829-56-6 | FFA | 0.19 µg/L (water) 4 | Beany, green (whole lupin)/Cardboard, fatty, green (dehulled lupin) | OI 49 (6 µg/g) | FD 256 | |||
| (Z)-2-Nonenal | 60784-31-8 | FFA 3 | 0.1 ppb 5 | Cardboard (dehulled lupin) | FD 32 | ||||
| (E,Z)-2,6-Nonadienal | 557-48-2 | FFA 3 | 45 µg/L (water) 4 | Sweet, fatty (whole lupin)/Cucumber, green (dehulled lupin) | OI 10 (7 µg/g) | FD 256 | |||
| (E,E,Z)-2,4,6-Nonatrienal | 100113-52-8 | FFA 3 | Nutty, oat-flake (dehulled lupin) | FD 256 | |||||
| (E)-4,5-Epoxy-(E)-decenal | 134454-31-2 | FFA 3 | 0.19 µg/L (water) 4 | Metallic (dehulled lupin) | FD 1024 | ||||
| (E,E)-2,4-Decadienal | 25152-84-5 | FFA | 0.038 µg/L (water) 4 | Peanut, grilled meat (peas) | %D 94 (Trace) | %D 83 (Coelution) | |||
| Alcohols | Pentanol | 71-41-0 | FFA | 1.6–70 ppm 5 | Grilled, dust (dehulled pea) | %D 28 (1.0 µg/g) | (NO–3.6 µg/g) | ||
| 1-Penten-3-ol | 616-25-1 | FFA | 400 ppb 5 | Beany, green (whole lupin) | (NO–4.6 µg/g) | (NO–1.4 µg/g) | OI 29 (26 µg/g) | ||
| 2-Methoxyphenol (guaiacol) | 90-05-1 | 3–31 ppb 5 | Sweet, phenolic (whole lupin) | OI 2 (4 µg/g) | |||||
| 2-Ethylhexanol | 104-76-7 | Floral (pea protein) | %D 56 (Coelution) | ||||||
| Octanol | 117-87-5 | FFA | 42–480 ppb 5 | Mushroom, vegetable (dehulled pea) | %D 83 (0.8 µg/g) | (NO–2.5 µg/g) | |||
| 1-Octen-3-ol | 3391-86-4 | FFA | 14 ppb 5 | Mushroom, vegetable (peas) | %D 94 (1.7 µg/g) | %D 78 (4.2 µg/g) | (NO – 78 µg/g) | ||
| Nonanol | 143-08-8 | FFA | 50–90 ppm 5 | Pea, vegetable, silt, earth (dehulled pea) | %D 78 (0.8 µg/g) | (ND) | |||
| Ketones | 2-Acetyl-1-pyrroline | 85213-22-5 | AA 3 | 99,000 µg/L (water) 4 | Popcorn (dehulled lupin) | FD 32 | |||
| Maltol | 118-71-8 | AA 3 | 35,000 µg/L (water) 4 | Caramel (dehulled lupin) | (ND) | (NO – Coelution) | FD 256 | ||
| Sotolone | 28664-35-9 | AA 6 | 2.1 µg/kg (cellulose) 4 | Spicy, savoury (dehulled lupin) | FD 256 | ||||
| 2,3-Butanedione | 431-03-8 | FFA 4 | 0.3–15 ppb 5 | Sweet, caramel, vanilla (whole lupin) | OI 17 (79 µg/g) | ||||
| 4-Methyl-2-pentanone | 108-10-1 | FFA 4 | 240–540 ppb 5 | Sweet, fruity, bubble gum (whole lupin) | OI 5 (0 µg/g) | ||||
| 2-Pentylfuran | 3777-69-3 | FFA | 6 ppb 5 | Oat, nutty (whole lupin) | OI 5 (172 µg/g) | ||||
| 1-Penten-3-one | 1629-58-9 | FFA 4 | 400 ppb 5 | Soil, green, herbal (whole lupin) | OI 28 (32 µg/g) | ||||
| 1-Octen-3-one | 4312-99-6 | FFA 3 | 0.016 µg/L (water) 5 | Mushroom, fungi (lupins) | OI 49 (2 µg/g) | FD 32 | |||
| 3-Octen-2-one | 1669-44-9 | FFA | 5–4 µg/L (water) 4 | Soil, earthy (whole lupin) | (ND) | (NO–2.5 µg/g) | OI 13 (2 µg/g) | ||
| 2,3-Octanedione | 585-25-1 | Mushroom, vegetable (peas) | %D 94 (Trace) | %D 78 (4.1 µg/g) | |||||
| (Z)-Octan-1,5-dien-3-one | 65213-86-7 | FFA 3 | Geranium, metallic (dehulled lupin) | FD 128 | |||||
| (E,E)-3,5-Octadien-2-one | 30086-02-3 | FFA | 0.15 ppm 5 | Vegetable, hay, earth (pea isolate) | (ND) | %D 100 (24.4 µg/g) | |||
| Undecanone | 112-12-9 | 7–82 ppb 5 | Floral, fruity (peas) | %D 22 (Trace) | %D 39 (0.6 µg/g) | ||||
| β-Ionone | 79-77-6 | CAR | 3.5 µg/L (water) 4 | Violet, flowery (dehulled lupin) | FD 512 | ||||
| Acids | Acetic acid | 64-19-7 | AA | 99,000 µg/L (water) 4 | Vinegar (dehulled lupin) | FD 32 | |||
| Phenylacetic acid | 103-82-2 | AA 7 | 6100 µg/L (water) 4 | Beeswax, honey (dehulled lupin) | FD 256 | ||||
| 2-Methylbutanoic acid | 116-53-0 | N, AA | 2200 µg/L (water) 4 | Sweaty, fruity, cheese (dehulled lupin) | (ND) | (ND) | FD 2048 | ||
| 3-Methylbutanoic acid | 503-74-2 | AA | 490 µg/L (water) 4 | Animal (dehulled pea)/Sweaty, fruity, cheese (dehulled lupin) | %D 22 (0.3 µg/g) | (ND) | FD 2048 | ||
| Pentanoic acid | 109-52-4 | AA 3 | 11,000 µg/L (water) 4 | Sweaty, fruity, cheese (dehulled lupin) | (NO–0.3 µg/g) | (ND) | FD 32 | ||
| Hexanoic acid | 142-62-1 | FFA | 93 ppb–10 ppm 5 | Faeces, meat broth, sewer (pea isolate) | (NO–0.5 µg/g) | %D 83 (Coelution) | |||
| Heptanoic acid | 111-14-8 | 640 ppb–10.4 ppm 5 | Animal, vomit (pea isolate) | (NO–1.0 µg/g) | %D 22 (ND) | ||||
| Lactones | γ-Octalactone | 104-50-7 | FFA | 6.5 g/L (water) 4 | Floral, anise, mint (peas)/ Coconut, sweet (dehulled lupin) |
%D 17 (Trace) | %D 94 (Trace) | FD 64 | |
| γ-Nonalactone | 104-61-0 | FFA | 9.7 µg/L (water) 4 | Sweet, candies, coconut (dehulled pea)/Coconut, sweet (dehulled lupin) | %D 72 (0.9 µg/g) | (NO – 1.0 µg/g) | FD 256 | ||
| 4-Hydroxy-2-noneic acid lactone | 21963-26-8 | FFA | Mint, strawberry, chlorophyll (peas) | %D 50 (0.5 µg/g) | %D 56 (3.2 µg/g) | ||||
| γ-Decalactone | 706-14-9 | FFA 3 | 1–11 ppb 5 | Peach, fruity (dehulled lupin) | FD 32 | ||||
| Pyrazines | 3-Isobutyl-2-methoxypyrazine | 24683-00-9 | AA | 62 µg/L (water) 4 | Woody, fresh pea (whole lupin)/Green pepper, earthy (dehulled lupin) | OI 70 (9 µg/g) | FD 32 | ||
| 2-Sec-Butyl-3-methoxypyrazine | 24168-70-5 | AA 4 | 1 ppb 5 | Woody, green (whole lupin) | OI 54 (1 µg/g) | ||||
| 3-Isopropyl-2-methoxypyrazine | 25773-40-4 | AA 4 | 39 µg/L (water) 4 | Soil, fresh green, woody (whole lupin)/Pea, green pepper (dehulled lupin) | OI 53 (0 µg/g) | FD 256 | |||
| 5or6-Methyl-3-isopropyl-2-methoxypyrazine | 32021-41-3 | AA | 3–7 ppb 5 | Plastic, cardboard, hay (dehulled pea)/Hay, dry, vegetable (pea isolate) | %D 50 (1.8 µg/g) | %D 83 (0.4 µg/g) | |||
| 3-Ethyl-2,5-dimethylpyrazine | 13360-65-1 | Potato, baked (whole lupin) | OI 65 (1 µg/g) | ||||||
| Others | Benzothiazole | 95-16-9 | AA 6 | 80–450 ppb 5 | Grilled meat (peas) | %D 39 (0.3 µg/g) | %D 39 (4.6 µg/g) | ||
| Dimethyl trisulfide | 3658-80-8 | 0.0099 µg/L (water) 4 | Faeces, meat broth, sewer (pea protein)/Meaty, metallic, sulphur (whole lupin) | (ND) | %D 83 (0.2 µg/g) | OI 14 (1 µg/g) | |||
1 [42]; 2 [54]; 3 [28]; 4 [55]; 5 [50]; 6 [31]; 7 [26]. DM, dry matter; FFA, free fatty acids; AA, amino acids; N, naturally present (not considered as a contaminant); CAR, carotenoids; ND, not detected; %D, percentage of detection; NO, detected but not odorant; OI, odour intensity; FD, factor dilution.