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[Identification of the key aroma compounds in cocoa powder based on molecular sensory correlations., Frauendorfer, Felix, Schieberle, Peter, Journal of agricultural and food chemistry, Vol.54(15) 2006, 5521-5529] [[http://worldcocoafoundation.org/wp-content/files_mf/frauendorfer2006.pdf]] | [Identification of the key aroma compounds in cocoa powder based on molecular sensory correlations., Frauendorfer, Felix, Schieberle, Peter, Journal of agricultural and food chemistry, Vol.54(15) 2006, 5521-5529] [[http://worldcocoafoundation.org/wp-content/files_mf/frauendorfer2006.pdf]] |
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"Cocoa beans (Theobroma cacao) are the major raw material for chocolate production and fermentation of the beans is essential for the development of chocolate flavor precursors. In this study, a novel approach was used to determine the role of yeasts in cocoa fermentation and their contribution to chocolate quality. Cocoa bean fermentations were conducted with the addition of 200 ppm Natamycin to inhibit the growth of yeasts, and the resultant microbial ecology and metabolism, bean chemistry and chocolate quality were compared with those of normal (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii and Kluyveromyces marxianus, the lactic acid bacteria Lactobacillus plantarum and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in the control fermentation. In fermentations with the presence of Natamycin, the same bacterial species grew but yeast growth was inhibited. Physical and chemical analyses showed that beans fermented without yeasts had increased shell content, lower production of ethanol, higher alcohols and esters throughout fermentation and lesser presence of pyrazines in the roasted product. Quality tests revealed that beans fermented without yeasts were purplish-violet in color and not fully brown, and chocolate prepared from these beans tasted more acid and lacked characteristic chocolate flavor. Beans fermented with yeast growth were fully brown in color and gave chocolate with typical characters which were clearly preferred by sensory panels. Our findings demonstrate that yeast growth and activity were essential for cocoa bean fermentation and the development of chocolate characteristics." \\ | Character impact compounds of the volatile fraction of three commercial cocoa powders (Bensdorp, Krüger, Sarotti) isolated using thin-layer high-vacuum distillation (TLHVD) of Soxhlet extracts were: Acetic acid (vinegar), propanoic acid (mouldy), 2-methyl propanoic acid (rancid), phenylacetaldehyde (flowery), 2/3-methyl butanoic acid (sweaty), dehydromevalonic acid lactone (condesed milk, sour), 2-pyrrolidinone (popcorn), pyrrole-2-carboxaldehyde (nut), (R)-(−)-pantolactone (caramel, coconut), furaneol (caramel), massoia lactone (coconut), dihydroxymaltol (caramel), 4-methyl-5-(2-hydroxyethyl)thiazol (peanut), two solerol isomers (red fruit, jam, green notes), vanillin (vanilla) and phenylacetic acid (sweet, flowery). These 17 compounds were detected at the sniff port of the GC-O after a 1:100 dilution. The aroma extract contained acetoin and several alkylated pyrazines e.g. \\ |
| [Krings, Ulrich, et al. "Thin-layer high-vacuum distillation to isolate volatile flavour compounds of cocoa powder." European Food Research and Technology 223.5 (2006): 675-681] |
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| "Cocoa beans (Theobroma cacao) are the major raw material for chocolate production and fermentation of the beans is essential for the development of chocolate flavor precursors. In this study, a novel approach was used to determine the role of yeasts in cocoa fermentation and their contribution to chocolate quality... Quality tests revealed that beans fermented without yeasts were purplish-violet in color and not fully brown, and chocolate prepared from these beans tasted more acid and lacked characteristic chocolate flavor. Beans fermented with yeast growth were fully brown in color and gave chocolate with typical characters which were clearly preferred by sensory panels. Our findings demonstrate that yeast growth and activity were essential for cocoa bean fermentation and the development of chocolate characteristics." \\ |
[Yeasts are essential for cocoa bean fermentation. Van Thi Thuy Ho, Jian Zhao, Graham Fleet, International Journal of Food Microbiology, Vol.174, 2014, 72-87] | [Yeasts are essential for cocoa bean fermentation. Van Thi Thuy Ho, Jian Zhao, Graham Fleet, International Journal of Food Microbiology, Vol.174, 2014, 72-87] |
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| "In contrast to cocoa from Ecuador, the Chontalpa cocoa shows an intense and distinctive fingerprint of alkyl pyrazines (2,3,5-trimethyl, 2,6 -dimethyl, 2,3-dimethyl, 2-ethyl-3,5-dimethyl, 2-ethyl-5(6)-methyl, and 3,5-diethyl-2-methyl pyrazine) and linear esters (e.g., ethyl pentanoate, ethyl hexanoate, ethyl octanoate, and ethyl decanoate). In addition, Chontalpa is characterized by a distinctive signature of some key aroma compounds, including acetic acid (sour), phenyl acetaldehyde (honey-like), 2-phenyl ethanol (flowery), phenyl propanoid derivates (benzaldehyde and benzyl alcohol), 3-methyl butanal (malty), and butanoic acid (sweaty). On the other hand, the Ecuador aroma signature results from 2-heptanol (citrusy), 3-methyl butanoic acid(rancid), and dimethyl trisulfide (sulfurous)." \\ |
| [Magagna, Federico, et al. "Advanced fingerprinting of high-quality cocoa: Challenges in transferring methods from thermal to differential-flow modulated comprehensive two dimensional gas chromatography." Journal of Chromatography A 1536 (2018): 122-136] [[https://aperto.unito.it/retrieve/handle/2318/1644892/351315/Manuscript%20OA_4aperto.pdf]] |
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**Chocolate** is a sweet food preparation of Theobroma cacao seeds. | **Chocolate** is a sweet food preparation of Theobroma cacao seeds. |
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| "Application of an aroma extract dilution analysis (AEDA) on the volatiles of a commercial milk chocolate revealed 51 odor-active compounds in the flavor dilution (FD) factor range 8−1024, 44 of which could be identified. The following 13 odorants contributed with the highest FD factors to the overall chocolate flavor: 3-methylbutanal (malty); 2-ethyl-3,5-dimethylpyrazine (potato chip-like); 2- and 3-methylbutanoic acid (sweaty); 5-methyl-(E)-2-hepten-4-one (hazelnut-like); 1-octen-3-one (mushroom-like); 2-ethyl-3,6-dimethylpyrazine (nutty, earthy); 2,3-diethyl-5-methylpyrazine (potato chip-like); (Z)-2-nonenal (green, tallowy); (E,E)-2,4-decadienal (fatty, waxy); (E,E)-2,4-nonadienal (fatty); R-δ-decalactone (sweet, peach-like); and 2-methyl-3-(methyldithio)furan. Application of the AEDA on the cocoa mass used in the production of the milk chocolate led to the identification of 37 odorants, seven of which were sensorially not detected in the chocolate. By contrast, 11 odorants were present in the milk chocolate but were not sensorially relevant in cocoa mass, e.g., R-δ-decalactone and 5-methyl-(E)-2-hepten-4-one." \\ |
| [Schnermann, Petra, and Peter Schieberle. "Evaluation of key odorants in milk chocolate and cocoa mass by aroma extract dilution analyses." Journal of Agricultural and Food Chemistry 45.3 (1997): 867-872] |
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"By application of the aroma extract dilution analysis on a flavor distillate obtained by high vacuum distillation of bitter chocolate 33 odor-active compounds were sensorially detected. Among the 29 odorants identified, vanillin, 2-methoxy-3-isopropylpyrazine, 2,3-diethyl-5-methylpyrazine followed by 2- and 3-methylbutanoic acid, 2-phenylethanol and 4-hydroxy-2,5-dimethyl-3(2H)-furanone showed the highest FD-factors. Compared to a milk chocolate, especially the FD-factors of the latter compound and the methoxypyrazine were much higher. In an extract obtained by simultaneous steam distillation/extraction of a milk chocolate, the concentration of, particularly, phenylacetaldehyde was increased by a factor of 120 compared to that in an extract obtained by the more careful high vacuum distillation. In addition, also 5-methyl-(E)-2-heptene-4-one, diacetyl and 3-methylbutanal were much higher in the SDE." \\ | "By application of the aroma extract dilution analysis on a flavor distillate obtained by high vacuum distillation of bitter chocolate 33 odor-active compounds were sensorially detected. Among the 29 odorants identified, vanillin, 2-methoxy-3-isopropylpyrazine, 2,3-diethyl-5-methylpyrazine followed by 2- and 3-methylbutanoic acid, 2-phenylethanol and 4-hydroxy-2,5-dimethyl-3(2H)-furanone showed the highest FD-factors. Compared to a milk chocolate, especially the FD-factors of the latter compound and the methoxypyrazine were much higher. In an extract obtained by simultaneous steam distillation/extraction of a milk chocolate, the concentration of, particularly, phenylacetaldehyde was increased by a factor of 120 compared to that in an extract obtained by the more careful high vacuum distillation. In addition, also 5-methyl-(E)-2-heptene-4-one, diacetyl and 3-methylbutanal were much higher in the SDE." \\ |
[Evaluation of solid-phase micro-extraction coupled to gas chromatography-mass spectrometry for the headspace analysis of volatile compounds in cocoa products. Ducki, S., Miralles-Garcia, J., Zumbé, A., Tornero, A., Storey, D. M., Talanta, Vol.74(5), 2008, 1166-1174] | [Evaluation of solid-phase micro-extraction coupled to gas chromatography-mass spectrometry for the headspace analysis of volatile compounds in cocoa products. Ducki, S., Miralles-Garcia, J., Zumbé, A., Tornero, A., Storey, D. M., Talanta, Vol.74(5), 2008, 1166-1174] |
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{{:theobroma_cacao.jpg}} \\ | "The specific cocoa aroma arises from complex biochemical and chemical reactions during the postharvest processing of raw beans, and from many influences of the cocoa genotype, chemical make‐up of raw seeds, environmental conditions, farming practices, processing, and manufacturing stages. There has been much research on cocoa flavor components. However, the relationships between all chemical components that are likely to play a role in cocoa flavor, their sensory properties, and the sources and mechanisms of flavor formation are not fully understood." \\ |
Theobroma cacao L.; Martius, C., Eichler, A.G., Urban, I., Flora Brasiliensis, vol.12(3) f.96 t.16 (1886) \\ | [Aprotosoaie, Ana Clara, Simon Vlad Luca, and Anca Miron. "Flavor chemistry of cocoa and cocoa products—an overview." Comprehensive Reviews in Food Science and Food Safety 15.1 (2016): 73-91] [[https://onlinelibrary.wiley.com/doi/full/10.1111/1541-4337.12180]] |
[[http://botanicalillustrations.org/species.php?id_species=1011749]] | |
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{{:theobroma_cacao.jpg}} \\ | {{:theobroma_cacao.jpg}} \\ |
[[http://botanicalillustrations.org/species.php?id_species=1011749]] | [[http://botanicalillustrations.org/species.php?id_species=1011749]] |
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| {{cacaofruits_starr.jpg?800}} \\ |
| Theobroma cacao fruits ripening along the trunk \\ |
| [[https://creativecommons.org/licenses/by-sa/3.0/de/|CC BY-SA 3.0]], Author: [[https://www.flickr.com/people/starr-environmental/|Forest and Kim Starr]] [[http://tropical.theferns.info/image.php?id=Theobroma+cacao|Useful Tropical Plants]] |