Coffee Leaf Tea from El Salvador: On-Site Production Considering Influences of Processing on Chemical Composition
Abstract
:1. Introduction
2. Materials and Methods
2.1. Coffee Leaf Tea Production in El Salvador
2.1.1. Drying Methods
2.1.2. Fermentation
2.1.3. Postprocessing and Packaging
2.2. Analysing of Non-Volatile Compounds
2.2.1. Sample Preparation for HPLC, NMR, NIR, and Photometry
2.2.2. Standard Analytical Procedures
2.2.3. Nuclear Magnetic Resonance (NMR) Spectrometry
2.3. Preliminary Sensory Analysis
2.4. Analysis of Volatile, Odour-Active Compounds
2.4.1. Tea Preparation
2.4.2. Direct-Immersion Stir Bar Sorptive Extraction (DI-SBSE)
2.4.3. Gas Chromatography
2.4.4. Odour Activity Value (OAV)
2.5. Statistical Analysis
3. Results and Discussion
3.1. Moisture Content of Fresh Leaves
3.2. Preparation of Coffee Leaf Tea Samples
3.3. Water Content, Essential Oil Content and Ash Content
3.4. Content of Caffeine and Catechins
3.4.1. Caffeine
3.4.2. Catechins
3.5. Content of Total Polyphenols
3.6. Content of Organic Acids and Trigonellin
3.6.1. Chlorogenic Acid
3.6.2. Lactic Acid
3.6.3. Acetic Acid
3.6.4. Trigonelline
3.7. Preliminary Sensory Evaluation
3.7.1. Personal Acceptance
3.7.2. Simple Descriptive Test
3.7.3. Profile Test
3.8. Aroma Analysis via DI-SBSE-GC-MS-O
3.8.1. Identification of Odour-Active Compounds
3.8.2. Semi-Quantification and Odour Activity Values
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Appendix A
Sample Number | Water (g/100 g) | Essential Oil (mL/100 g) | Ash (g/100 g) |
---|---|---|---|
1 | 7.71 ± 0.15 | 1.08 ± 0.09 | 8.41 ± 0.19 |
2 | 9.68 ± 0.36 | 0.79 ± 0.07 | 10.20 ± 0.20 |
3 | 8.26 ± 0.13 | 0.46 ± 0.21 | 8.88 ± 0.99 |
4 | 10.07 ± 0.11 | 0.66 ± 0.11 | 9.85 ± 0.11 |
5 | 9.77 ± 0.24 | 0.52 ± 0.5 | 9.46 ± 1.01 |
6 | 7.86 ± 0.03 | 0.47 ± 0.06 | 7.94 ± 0.23 |
7 | 9.24 ± 0.23 | 0.76 ± 0.06 | 8.14 ± 0.08 |
8 | 5.99 ± 0.13 | 1.52 ± 0.08 | 9.98 ± 0.08 |
9 | 6.27 ± 0.11 | 1.28 ± 0.20 | 9.64 ± 0.10 |
10 | 7.11 ± 0.26 | 1.16 ± 0.07 | 9.00 ± 0.09 |
11 | 6.84 ± 0.14 | 1.20 ± 0.03 | 8.95 ± 0.10 |
12 | 8.12 ± 0.24 | 1.04 ± 0.29 | 9.29 ± 0.88 |
13 | 7.85 ± 0.22 | 1.31 ± 0.06 | 8.53 ± 0.16 |
14 | 8.35 ± 0.13 | 1.25 ± 0.16 | 8.52 ± 0.37 |
15 | 5.52 ± 0.26 | 0.00 ± 0.00 | 9.89 ± 0.14 |
16 | 17.42 ± 0.04 | 0.30 ± 0.01 | 3.22 ± 0.00 |
17 | 6.56 ± 0.12 | 0.02 ± 0.03 | 8.54 ± 0.09 |
18 | 6.75 ± 0.13 | 0.39 ± 0.02 | 7.82 ± 0.14 |
19 | 8.25 ± 0.30 | 0.00 ± 0.00 | 7.81 ± 0.05 |
20 | 5.39 ± 0.04 | 0.37 ± 0.31 | 9.00 ± 0.86 |
21 | 5.99 ± 0.1 | 0.01 ± 0.02 | 9.85 ± 0.92 |
22 | 6.58 ± 0.06 | 0.09 ± 0.04 | 8.62 ± 0.21 |
23 | 3.92 ± 0.06 | 1.48 ± 0.05 | 8.10 ± 0.16 |
24 | 6.58 ± 0.02 | 0.30 ± 0.26 | 9.55 ± 0.81 |
Sample Number | Caffeine (g/100 g DM) | Epigallocatechin Gallate (g/100 g DM) | Total Catechins (g/100 g DM) | Theobromin (g/100 g DM) |
---|---|---|---|---|
1 | 0.740 ± 0.003 | - | 0.306 ± 0.006 | - |
2 | 0.565 ± 0.004 | - | 0.299 ± 0.002 | 0.021 ± 0.001 |
3 | 0.747 ± 0.010 | - | 0.390 ± 0.023 | - |
4 | 0.520 ± 0.001 | - | 0.290 ± 0.002 | 0.015 ± 0.001 |
5 | 0.699 ± 0.027 | - | 0.208 ± 0.090 | - |
6 | 0.693 ± 0.026 | - | 0.206 ± 0.089 | - |
7 | 0.713 ± 0.006 | - | 0.345 ± 0.004 | - |
8 | 0.669 ± 0.001 | - | 0.054 ± 0.003 | - |
9 | 0.396 ± 0.003 | - | - | - |
10 | 0.406 ± 0.003 | - | - | - |
11 | 0.444 ± 0.001 | - | - | - |
12 | 0.392 ± 0.003 | - | - | - |
13 | 0.370 ± 0.001 | - | - | - |
14 | 0.368 ± 0.004 | - | - | - |
15 | 0.380 ± 0.004 | - | - | - |
16 | 0.449 ± 0.001 | - | - | - |
17 | 0.462 ± 0.003 | - | - | - |
18 | 0.939 ± 0.596 | - | 0.221 ± 0.157 | - |
19 | 1.333 ± 0.019 | - | 0.699 ± 0.009 | 0.009 ± 0.003 |
20 | 0.381 ± 0.003 | - | 0.045 ± 0.007 | - |
21 | 0.761 ± 0.012 | - | 0.092 ± 0.008 | - |
22 | 1.000 ± 0.004 | - | - | - |
23 | 0.894 ± 0.008 | - | 0.479 ± 0.001 | - |
24 | 0.858 ± 0.003 | - | 0.091 ± 0.128 | - |
Sample Number | Total Polyphenol (g/100 g DM) |
---|---|
1 | 8.28 ± 0.33 |
2 | 9.34 ± 0.36 |
3 | 7.62 ± 0.26 |
4 | 8.31 ± 0.22 |
5 | 7.54 ± 0.67 |
6 | 3.73 ± 0.28 |
7 | 7.15 ± 0.18 |
8 | 4.76 ± 0.13 |
9 | 0.91 ± 0.12 |
10 | 1.68 ± 0.75 |
11 | 1.50 ± 0.81 |
12 | 2.35 ± 0.66 |
13 | 2.04 ± 0.82 |
14 | 2.18 ± 0.82 |
15 | 0.91 ± 0.08 |
16 | 1.08 ± 0.00 |
17 | 1.15 ± 0.00 |
18 | 7.91 ± 0.77 |
19 | 10.36 ± 0.25 |
20 | 2.73 ± 0.45 |
21 | 0.79 ± 0.11 |
22 | - |
23 | 5.93 ± 0.27 |
24 | 5.08 ± 0.19 |
Sample | Chlorogenic Acid (g/100 g DM) | Acetic Acid (g/100 g DM) | Lactic Acid (g/100 g DM) | Trigonellin (g/100 g DM) |
---|---|---|---|---|
1 | 2.92 | 0.107 | 0.18 | 2.79 |
2 | 2.58 | 0.088 | 0.16 | 0.98 |
3 | 2.38 | 0.101 | 0.13 | 2.66 |
4 | 2.81 | 0.097 | 0.15 | 1.15 |
5 | 3.78 | 0.136 | 0.14 | 2.76 |
6 | 1.17 | 0.068 | 0.11 | 1.80 |
7 | 3.32 | 0.124 | 0.13 | 2.66 |
8 | 1.44 | 0.114 | 0.11 | 2.25 |
9 | 0.20 | 0.145 | 8.12 | 1.26 |
10 | 0.16 | 0.102 | 0.21 | 1.21 |
11 | 0.08 | 0.266 | 0.92 | 1.28 |
12 | 0.23 | 0.115 | 0.21 | 0.62 |
13 | 0.18 | 0.093 | 0.20 | 0.68 |
14 | 0.24 | 0.21 | 1.08 | 0.62 |
15 | 0.08 | 0.137 | 2.76 | 1.44 |
16 | 0.00 | 0.051 | 0.49 | 1.11 |
17 | 0.06 | 0.29 | 2.59 | 1.01 |
18 | 9.35 | 0.061 | 0.16 | 4.87 |
19 | 6.58 | 0.078 | 0.22 | 4.25 |
20 | 2.82 | 0.078 | 0.14 | 2.34 |
21 | 0.31 | 0.122 | 0.49 | 2.01 |
22 | 0.31 | 0.042 | 0.12 | 3.30 |
23 | 6.20 | 0.14 | 0.14 | 3.31 |
24 | 3.00 | 0.074 | 0.23 | 2.41 |
Number | Compound | RI | RI (lit/std) | Odour | Identification | 182 | 687 | 234 | 156 | 930 | 743 | 147 | 369 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Hexanal | 1079 | 1079 | green, grassy | RI,MS,O | X | X | X | X | X | X | X | X |
2 | 4-Heptenal | 1242 | 1239 | green | RI,MS,O | X | X | X | X | ||||
3 | Octanal | 1285 | 1286 | fruity | RI,MS,O | X | |||||||
4 | n.i. | 1298 | - | green | / | X | |||||||
5 | 1-Hydroxy-2-propanone a | 1307 | 1305 | sweetish | RI,O | X | |||||||
6 | 2,3 Dimethylpyrazin | 1347 | 1347 | - | RI,MS | X | |||||||
7 | 1-Hexanol a | 1357 | 1357 | sweetish green | RI,O | X | |||||||
8 | n.i. | 1370 | - | green/cucumber | / | X | |||||||
9 | (E)-2-Octenal | 1430 | 1430 | cucumber | RI,MS,O | X | X | X | |||||
10 | (E)-4-Nonenal a | 1435 | 1435 | fruity | RI,O | X | |||||||
11 | n.i. | 1449 | - | melon | / | X | |||||||
12 | 1-Octen-3-ol | 1453 | 1452 | forest | RI,MS,O | X | |||||||
13 | n.i. | 1465 | - | fruity | / | X | |||||||
14 | 3-Ethyl-3,5-dimethyl-pyrazine a | 1468 | 1466 | roasty, coffee | RI,O | X | |||||||
15 | Decanal | 1502 | 1497 | citrus, floral | RI,MS,O | X | X | X | X | X | X | X | X |
16 | 2-Ethyl-3,5-dimethylpyrazine | 1512 | 1512 | - | RI,MS | X | |||||||
17 | (E,E)-3,5-Octadien-2-one a | 1519 | 1521 | green, grassy | RI,O | X | |||||||
18 | Benzaldehyde | 1523 | 1522 | sweetish fruity | RI,MS,O | X | |||||||
19 | n.i. | 1530 | - | green, grassy | / | X | |||||||
20 | (E)-2-Nonenal | 1536 | 1537 | citrus like | RI,MS,O | X | |||||||
21 | n.i. | 1560 | - | green, grassy | / | X | |||||||
22 | n.i. | 1562 | - | green, grassy | / | X | |||||||
23 | 2,6-Nonadienal | 1587 | 1586 | cucumber | RI,MS,O | X | X | X | X | X | X | X | X |
24 | 5H-5-Methyl-6,7-dihydrocyclopentapyrazine a | 1629 | 1630 | peanut | RI,O | X | |||||||
25 | (E,E)-2,4-Nonadienal a | 1699 | 1698 | melon,cucumber | RI,O | X | |||||||
26 | α-Terpineol | 1699 | 1699 | citrus like | RI,MS,O | X | X | ||||||
27 | n.i. | 1700 | - | citrus like | / | X | X | ||||||
28 | 2,4-Nonadienal | 1702 | 1700 | melon,cucumber | RI,MS,O | X | |||||||
29 | 2,3-Nonadienal a | 1703 | 1703 | melon,cucumber | RI,O | X | |||||||
30 | 4-Ethyl-benzaldehyde a | 1709 | 1711 | fruity | RI,O | X | |||||||
31 | n.i. | 1712 | - | pineapple | / | X | |||||||
32 | (E,Z)-2,6-Nonadien-1-ol a | 1769 | 1770 | green, cucumber | RI,O | X | X | X | |||||
33 | 3,7,11-Trimethyl-1-dodecanol a | 1770 | green | RI,O | X | ||||||||
36 | 3,4-Dimethylbenzaldehyde a | 1811 | 1790 | sweetish, green | RI,O | X | X | X | X | X | |||
37 | 2,5-Dimethylbenzaldehyde a | 1812 | 1812 | sweetish, green | RI,O | X | |||||||
38 | Hexanoic acid a | 1844 | 1844 | fatty | RI,O | X | |||||||
39 | Dodecanoic acid, ethyl ester a | 1846 | 1846 | sweetish, floral | RI,O | X | |||||||
40 | α-Ionone | 1857 | 1855 | sweetish, floral | RI,MS,O | X | X | X | X | X | X | X | X |
41 | n.i. | 1874 | - | green | / | X | |||||||
42 | Benzyl alcohol | 1878 | 1877 | fruity | RI,MS,O | X | |||||||
43 | β-Ionone | 1942 | 1943 | honey, flower | RI,MS,O | X | X | X | X | X | X | X | X |
44 | 1-Dodecanol | 1969 | 1971 | cocutnut | RI,MS,O | X | |||||||
45 | n.i. | 2005 | - | green | / | X | X | X | |||||
46 | n.i. | 2007 | - | green | / | X | X | ||||||
47 | 4-Methoxybenzaldehyde | 2027 | 2025 | vanilla | RI,MS,O | X | X | X | |||||
48 | n.i. | 2034 | - | cocutnut | RI,MS,O | X | |||||||
49 | n.i. | 2078 | - | green, cucumber | / | X | X | ||||||
50 | n.i. | 2081 | - | green, cucumber | / | X | |||||||
51 | 1-Ethylundecylbenzene a | 2092 | 2094 | herbal | RI,O | X | |||||||
52 | n.i. | 2094 | - | herbal | / | X | X | ||||||
53 | n.i. | 2096 | - | herbal | / | X | X | X | |||||
55 | n.i. | 2155 | - | green, cucumber | / | X | X | X | |||||
56 | 1-Methyldodecylbenzene a | 2158 | mint | RI,O | X | ||||||||
57 | Nonanoic acid | 2168 | 2164 | sweetish green | RI,MS,O | X | X | X | |||||
58 | Tetrahydro-6-pentyl-2H-pyran-2-one a | 2201 | 2201 | cocotnut | RI,O | X | |||||||
59 | Isopropyl palmitate a | 2242 | 2237 | sweetish | RI,O | X | |||||||
60 | n.i. | 2251 | - | citrus like | / | X | |||||||
61 | Dihydro-5-pentyl-2(3H)-furanone a | 2264 | 2266 | cocutnut | RI,O | X | X | ||||||
62 | 5-Heptyldihydro-2(3H)-furanone a | 2264 | roasty, coffee | RI,O | X | ||||||||
63 | γ-Dodecalactone | 2381 | 2379 | fruity | RI,MS,O | X | X | ||||||
64 | n.i. | 2397 | - | aquarium | / | X | |||||||
65 | (Z)-Dihydro-5(2-octenyl)-2(2H)-furanone a | 2402 | 2390 | green, sweetish | RI,O | X | |||||||
66 | n.i. | 2402 | - | green, sweetish | / | X | X | X | X | ||||
67 | Indole | 2449 | 2443 | Nutty | RI,MS,O | X | |||||||
68 | n.i. | 2471 | - | Stable | / | X |
Compound | Concentration in µg/L | OAV |
---|---|---|
β-Ionone | 3.44 ± 0.33 | 491 |
(E,Z)-2,6-Nonadienal | 2.56 ± 0.36 | 256 |
α-Ionone | 3.01 ± 0.59 | 100 |
Octanal | 12.87 ± 0.93 | 18 |
Decanal | 1.69 ± 0.15 | 17 |
4-Heptenal | 7.15 ± 1.22 | 9 |
Hexanal | 28.4 ± 4.19 | 6 |
(E)-2-Nonenal | 0.22 ± 0.02 | 3 |
1-Dodecanol | 0.33 ± 0.09 | <1 |
3-Hexen-1-ol | 28.91 ± 3.76 | <1 |
α-Terpineol | 0.76 ± 0.08 | <1 |
1-Dodecanol | 0.3 ± 0.03 | <1 |
(E)-2-Octenal | 1.78 ± 0.19 | <1 |
Nonanoic acid | 638.8 ± 36.55 | <1 |
Benzyl alcohol | 147.73 ± 26.28 | <1 |
(E,E)-2,4-Heptadienal | 101.17 ± 6.95 | <1 |
γ-Dodecalactone | 2.54 ± 0.43 | <1 |
Compound | Concentration in g/L | OAV |
---|---|---|
β-Ionone | 0.93 ± 0.05 | 132 |
(E,Z)-2,6-Nonadienal | 0.49 ± 0.06 | 49 |
α-Ionone | 0.9 ± 0.04 | 30 |
Decanal | 1.41 ± 0.16 | 14 |
Octanal | 6.72 ± 1.05 | 10 |
2,4-Nonadienal | 0.76 ± 0.13 | 8 |
Hexanal | 23.46 ± 3.89 | 5 |
(E)-2-Nonenal | 0.26 ± 0.01 | 3 |
4-Heptenal | 2.21 ± 0.37 | 3 |
1-Dodecanol | 0.38 ± 0.07 | <1 |
3-Hexen-1-ol | 41 ± 8.15 | <1 |
α-Terpineol | 0.82 ± 0.11 | <1 |
1-Dodecanol | 0.13 ± 0.01 | <1 |
(E)-2-Octenal | 0.39 ± 0.06 | <1 |
Nonanoic acid | 730.46 ± 13.3 | <1 |
Benzyl alcohol | 53.87 ± 7.15 | <1 |
(E,E)-2,4-Heptadienal | 25.07 ± 1.45 | <1 |
γ-Dodecalactone | 2 ± 0.36 | <1 |
Benzaldehyde | 2.71 ± 0.28 | <1 |
Compound | Concentration in µg/L | OAV |
---|---|---|
β-Ionone | 1.75 ± 0.07 | 249 |
Decanal | 5.37 ± 0.91 | 54 |
α-Ionone | 1.39 ± 0.04 | 46 |
(E,Z)-2,6-Nonadienal | 0.18 ± 0.03 | 18 |
Octanal | 5.75 ± 0.71 | 8 |
2,4-Nonadienal | 0.28 ± 0.03 | 3 |
4-Heptenal | 1.97 ± 0.34 | 2 |
(E)-2-Nonenal | 0.19 ± 0.02 | 2 |
Hexanal | 9.28 ± 1.6 | 2 |
1-Dodecanol | 0.24 ± 0.03 | <1 |
1-Octen-3-ol | 0.63 ± 0.1 | <1 |
3-Hexen-1-ol | 14.35 ± 2.77 | <1 |
α-Terpineol | 1.13 ± 0.06 | <1 |
(E)-2-Octenal | 0.1 ± 0.02 | <1 |
Nonanoic acid | 1199.03 ± 347.21 | <1 |
Benzyl alcohol | 33.6 ± 3.78 | <1 |
γ-Dodecalactone | 0.05 ± 0 | <1 |
Benzaldehyde | 5.66 ± 0.37 | <1 |
Indole | 3.32 ± 0.13 | <1 |
Compound | Concentration in µg/L | OAV |
---|---|---|
β-Ionone | 2.14 ± 0.15 | 306 |
Decanal | 26.83 ± 3.29 | 268 |
(E,Z)-2,6-Nonadienal | 0.78 ± 0.21 | 78 |
α-Ionone | 2.13 ± 0.06 | 71 |
Octanal | 15.84 ± 2.13 | 23 |
2,4-Nonadienal | 1.01 ± 0.01 | 11 |
(E)-2-Nonenal | 0.74 ± 0.04 | 9 |
Hexanal | 38.98 ± 1.25 | 9 |
4-Heptenal | 4.65 ± 0.72 | 6 |
1-Dodecanol | 0.73 ± 0.08 | <1 |
3-Hexen-1-ol | 40.6 ± 1.07 | <1 |
α-Terpineol | 1.46 ± 0.15 | <1 |
(E)-2-Octenal | 0.67 ± 0.08 | <1 |
Nonanoic acid | 1508.67 ± 310.48 | <1 |
Benzyl alcohol | 130.01 ± 14.89 | <1 |
(E,E)-2,4-Heptadienal | 57 ± 4.83 | <1 |
γ-Dodecalactone | 0.16 ± 0.03 | <1 |
Benzaldehyde | 6.5 ± 0.76 | <1 |
Benzaldehyde, 4-methoxy- | 1.83 ± 0.07 | <1 |
Compound | Concentration in µg/L | OAV |
---|---|---|
β-Ionone | 2.95 ± 0.23 | 421 |
Decanal | 30.06 ± 3.49 | 301 |
α-Ionone | 1.39 ± 0.07 | 46 |
(E,Z)-2,6-Nonadienal | 0.31 ± 0.03 | 31 |
2,4-Nonadienal | 1.66 ± 0.06 | 18 |
Octanal | 12.37 ± 1.9 | 18 |
(E)-2-Nonenal | 0.86 ± 0.12 | 11 |
Hexanal | 36.85 ± 3.52 | 8 |
4-Heptenal | 0.81 ± 0.06 | 1 |
1-Dodecanol | 0.96 ± 0.09 | <1 |
3-Hexen-1-ol | 57.73 ± 10.8 | <1 |
α-Terpineol | 6.01 ± 0.84 | <1 |
(E)-2-Octenal | 0.37 ± 0.06 | <1 |
Nonanoic acid | 1462.18 ± 228.82 | <1 |
Benzyl alcohol | 20.44 ± 0.05 | <1 |
(E,E)-2,4-Heptadienal | 21.27 ± 1.36 | <1 |
γ-Dodecalactone | 0.06 ± 0.01 | <1 |
Benzaldehyde | 3.56 ± 0.31 | <1 |
Indole | 1.9 ± 0.07 | <1 |
Compound | Concentration in µg/L | OAV |
---|---|---|
β-Ionone | 3.79 ± 0.31 | 541 |
α-Ionone | 1.96 ± 0.06 | 65 |
Decanal | 4.7 ± 0.54 | 47 |
(E,Z)-2,6-Nonadienal | 0.39 ± 0.04 | 39 |
2,4-Nonadienal | 0.65 ± 0.06 | 7 |
Octanal | 5.02 ± 0.19 | 7 |
Hexanal | 31.71 ± 2.48 | 7 |
4-Heptenal | 2.84 ± 0.29 | 4 |
(E)-2-Nonenal | 0.24 ± 0.03 | 3 |
1-Dodecanol | 0.66 ± 0.05 | <1 |
1-Octen-3-ol | 0.58 ± 0.11 | <1 |
3-Hexen-1-ol | 50.56 ± 6.39 | <1 |
α-Terpineol | 0.89 ± 0.08 | <1 |
(E)-2-Octenal | 0.19 ± 0.01 | <1 |
Nonanoic acid | 949.75 ± 121.15 | <1 |
Benzyl alcohol | 35.32 ± 3.23 | <1 |
(E,E)-2,4-Heptadienal | 24.74 ± 1.93 | <1 |
γ-Dodecalactone | 0.05 ± 0.01 | <1 |
Benzaldehyde | 6.07 ± 0.93 | <1 |
Indole | 3.14 ± 0.34 | <1 |
Compound | Concentration in µg/L | OAV |
---|---|---|
β-Ionone | 6.49 ± 0.67 | 927 |
α-Ionone | 2.66 ± 0.25 | 89 |
Decanal | 7.38 ± 0.86 | 74 |
(E,Z)-2,6-Nonadienal | 0.2 ± 0.03 | 20 |
Octanal | 11 ± 0.89 | 16 |
Hexanal | 42.82 ± 2.57 | 10 |
2,4-Nonadienal | 0.74 ± 0.09 | 8 |
4-Heptenal | 3.31 ± 0.07 | 4 |
1-Dodecanol | 0.38 ± 0.04 | <1 |
1-Octen-3-ol | 0.3 ± 0.05 | <1 |
3-Hexen-1-ol | 44.86 ± 5 | <1 |
α-Terpineol | 1.7 ± 0.24 | <1 |
(E)-2-Octenal | 0.19 ± 0.02 | <1 |
Nonanoic acid | 1235.09 ± 11.07 | <1 |
Benzyl alcohol | 35.18 ± 2.8 | <1 |
(E,E)-2,4-Heptadienal | 11.5 ± 1.07 | <1 |
γ-Dodecalactone | 0.05 ± 0 | <1 |
Benzaldehyde | 5.84 ± 0.68 | <1 |
Indole | 1.61 ± 0.13 | <1 |
Benzaldehyde, 4-methoxy- | 0.9 ± 0.15 | <1 |
Compound | Concentration in µg/L | OAV |
---|---|---|
β-Ionone | 2.57 ± 0.12 | 367 |
α-Ionone | 0.97 ± 0.03 | 32 |
Octanal | 7.97 ± 0.41 | 11 |
1-Octen-3-ol | 5.07 ± 0.19 | 5 |
2,4-Nonadienal | 0.22 ± 0.01 | 2 |
2-ethyl-3,5-dimethylpyrazine | 0.1 ± 0.01 | 2 |
(E)-2-Nonenal | 0.1 ± 0.01 | 1 |
Hexanal | 5.66 ± 0.24 | 1 |
2,3-dimethylpyrazine | 2.85 ± 0.11 | 1 |
1-Dodecanol | 0.43 ± 0.02 | <1 |
3-Hexen-1-ol | 29.8 ± 1.1 | <1 |
α-Terpineol | 0.2 ± 0.02 | <1 |
1-Dodecanol | 0.29 ± 0.01 | <1 |
(E)-2-Octenal | 0.1 ± 0.01 | <1 |
Nonanoic acid | 951.9 ± 121.64 | <1 |
Benzyl alcohol | 47.66 ± 5.34 | <1 |
(E,E)-2,4-Heptadienal | 0.93 ± 0.05 | <1 |
γ-Dodecalactone | 0.06 ± 0.01 | <1 |
Benzaldehyde | 2.92 ± 0.2 | <1 |
Indole | 6.58 ± 0.43 | <1 |
2,5-Dimethyl-3-(2-methylpropyl)-pyrazine | 2.6 ± 0.03 | <1 |
Compound | Odour Threshold [ppb] | |
---|---|---|
α-Terpineol | 330 | Takeoka et al., 1990 [60] |
1-Dodecanol | 7.1 | Pal et al., 2014 [61] |
1-Octen-3-ol | 1 | Buttery et al., 1988 [62] |
2-ethyl-3,5-dimethylpyrazine | 0.04 | Buttery and Ling, 1997 [63] |
2-Nonenal, (E)- | 0.08 | Buttery et al., 1988 [62] |
2-Octenal, (E)- | 3 | Guadagni et al., 1972 [64] |
2,3-dimethylpyrazine | 2.5 | |
2,4-Heptadienal, (E,E)- | 778 | |
2,4-Nonadienal | 0.09 | Teranishi et al., 1974 [65] |
2,5-Dimethyl-3-(2-methylpropyl)-pyrazine | 800 | |
2,6-Nonadienal, (E,Z)- | 0.01 | Teranishi et al., 1974 [65] |
3-Hexen-1-ol | 70 | Takeoka et al., 1990 [60] |
4-Heptenal | 0.8 | |
Benzaldehyde | 350 | Buttery et al., 1988 [62] |
Benzaldehyde, 4-methoxy- | 47 | |
Benzyl alcohol | 10000 | Buttery et al., 1988 [62] |
Decanal | 0.1 | Guadagni et al., 1963 [66] |
Hexanal | 04.05.05 | Buttery et al., 1988 [62] |
Indole | 140 | Buttery et al., 1988 [62] |
Nonanoic acid | 3000 | |
Octanal | 0.7 | Buttery et al., 1988 [62] |
α-Ionone | 0.03 | |
β-Ionone | 0.007 | |
γ-Dodecalactone | 7 | Engel et al., 1988 [67] |
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Leaf Type | Coffea arabica Variety | Collection Place |
---|---|---|
Old leaf | Pacamara | Finca La Palma |
Yellow leaf | Pacamara | Finca La Palma |
Old leaf | Bourbon Tekisic | Finca La Quintanilla |
Young leaf | Bourbon Tekisic | Finca La Quintanilla |
Shoot | Bourbon Tekisic | Finca La Quintanilla |
Processing | Explanation |
---|---|
None (whole leaf) | No further mechanical intervention. |
Blending | The leaves were blended in a kitchen blender. For 100 g leaves, around 400 mL tap water was added. |
Cutting | Leaves were cut with a kitchen knife to small strips (20 mm wide). |
Rolling | The leaves were rolled by hand. |
Freezing | The leaves were frozen in a freezer at −20 °C for 2 days. |
Crumbling | Leaves were crumbled by hand. |
Steaming | Leaves were steamed in a 50 L pot. A sieve was placed in the centre of the pot and approximately 2 L of tap water was boiled under the leaves. The temperature was measured at the lid of the pot. The process was stopped when the temperature reached around 100 °C. |
Leaf Type | Moisture Content [%] |
---|---|
Pacamara yellow | 56.28 ± 1.02 |
Shoots Bourbon whole | 72.74 ± 1.73 |
Bourbon old | 62.83 ± 2.22 |
Bourbon young | 72.89 ± 0.99 |
Test No. | Coffea arabica Variety | Leaf Type | Processing | Drying | Fermentation | |
---|---|---|---|---|---|---|
1 | 936 | Pacamara | old | whole | air | none |
2 | 324 | Pacamara | yellow | whole | air | none |
3 | 742 | Pacamara | old | crumbled | air | none |
4 | 183 | Pacamara | yellow | crumbled | air | none |
5 | 502 | Pacamara | old | cutted | air | none |
6 | 643 | Pacamara | old | blended | air | none |
7 | 842 | Pacamara | old | crumbled | air | Yeast |
8 | 234 | Pacamara | old | whole | oven | none |
9 | 238 | Pacamara | old | blended | air | Lactobacillus |
10 | 182 | Pacamara | old | blended | air | Yeast |
11 | 789 | Pacamara | old | blended | air | Wild |
12 | 156 | Pacamara | yellow | blended | air | Wild |
13 | 687 | Pacamara | yellow | blended | air | Yeast |
14 | 463 | Pacamara | yellow | blended | air | Lactobacillus |
15 | 289 | Bourbon | shoot | blended | air | Wild |
16 | 138 | Bourbon | old | blended | air | Yeast |
17 | 147 | Bourbon | young | blended | air | Wild |
18 | 392 | Bourbon | young | steamed/rolled | air | none |
19 | 305 | Bourbon | young | rolled/fermented | air | Wild |
20 | 930 | Bourbon | shoot | blended/steamed | air | none |
21 | 743 | Bourbon | old | whole | air | Wild |
22 | 901 | Bourbon | old | whole/frozen | air | none |
23 | 369 | Bourbon | old | whole | roasted | none |
24 | 220 | Bourbon | shoot | whole | air | none |
Test Number | Ranking | Colour | Odour | Flavour |
---|---|---|---|---|
687 | 1 | sediment turbid red-brown | peach-like | peach-like |
182 | 2 | clear red | floral woody | sweet peach-like |
369 | 3 | clear yellow-brown | popcorn-like smoky roasty | popcorn-like roasty |
147 | 4 | very clear yellow-brown | chestnut flower-like floral | honey-like grassy |
156 | 5 | red clear | honey floral | honey-like acacia flower-like |
234 | 6 | clear amber | grassy rooibos-like | green bean-like vegetal |
930 | 7 | clear yellow-green | floral sweet | floral basil-like |
743 | 8 | turbid light orange | green bean-like | grassy green bean-like broccoli-like |
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Steger, M.C.; Rigling, M.; Blumenthal, P.; Segatz, V.; Quintanilla-Belucci, A.; Beisel, J.M.; Rieke-Zapp, J.; Schwarz, S.; Lachenmeier, D.W.; Zhang, Y. Coffee Leaf Tea from El Salvador: On-Site Production Considering Influences of Processing on Chemical Composition. Foods 2022, 11, 2553. https://doi.org/10.3390/foods11172553
Steger MC, Rigling M, Blumenthal P, Segatz V, Quintanilla-Belucci A, Beisel JM, Rieke-Zapp J, Schwarz S, Lachenmeier DW, Zhang Y. Coffee Leaf Tea from El Salvador: On-Site Production Considering Influences of Processing on Chemical Composition. Foods. 2022; 11(17):2553. https://doi.org/10.3390/foods11172553
Chicago/Turabian StyleSteger, Marc C., Marina Rigling, Patrik Blumenthal, Valerie Segatz, Andrès Quintanilla-Belucci, Julia M. Beisel, Jörg Rieke-Zapp, Steffen Schwarz, Dirk W. Lachenmeier, and Yanyan Zhang. 2022. "Coffee Leaf Tea from El Salvador: On-Site Production Considering Influences of Processing on Chemical Composition" Foods 11, no. 17: 2553. https://doi.org/10.3390/foods11172553
APA StyleSteger, M. C., Rigling, M., Blumenthal, P., Segatz, V., Quintanilla-Belucci, A., Beisel, J. M., Rieke-Zapp, J., Schwarz, S., Lachenmeier, D. W., & Zhang, Y. (2022). Coffee Leaf Tea from El Salvador: On-Site Production Considering Influences of Processing on Chemical Composition. Foods, 11(17), 2553. https://doi.org/10.3390/foods11172553