Abstract
With the rising interest by consumers for high-quality cocoa products from a clear geographical origin, a rapid analytical method for quality control, authenticity and traceability assessment is of paramount importance. However, the complex mixture of volatiles present in cocoa liquor, the main ingredient for the chocolate production, complicates reaching this purpose. Hence, an analytical fingerprint approach using advanced electronic nose (E-nose) technology may offer a suitable technique. This study aimed to verify the suitability of an E-nose based on ultra-fast gas chromatography (GC) for the rapid discrimination between cocoa liquors from different origins. Fourteen cocoa liquors, produced of cocoa beans from ten different geographical origins, were analyzed. The obtained odor fingerprints were investigated using principal component analysis (PCA) which successfully discriminated most cocoa liquors, within one continent, according to their geographical origin. Besides, discriminant factor analysis (DFA) showed the possibility to differentiate between bulk and fine cocoa. Further tentative identification of predominant volatile compounds allowed the detection of compounds within a wide range of chemical classes occurring in cocoa products, such as acids, alcohols, aldehydes, ketones, esters, pyrazines, pyrones, and pyrroles. Most odorant compounds were previously described in literature as key volatiles in cocoa flavor, notable examples are acetic acid, 2-heptanol, 2/3-methylbutanal, acetophenone, isoamyl acetate, tetramethylpyrazine, maltol, and 2-acetyl-1-pyrroline. This study proves for the first time the usefulness of the GC E-nose for effective and rapid aroma profiling and discrimination between single origin cocoa liquors, which can be easily applied in the cocoa industry.
Similar content being viewed by others
References
Acierno V, Yener S, Alewijn M, Biasioli F, van Ruth S (2016) Factors contributing to the variation in the volatile composition of chocolate: botanical and geographical origins of the cocoa beans, and brand-related formulation and processing. Food Res Int 84:86–95
Afoakwa EO, Paterson A, Fowler M, Ryan A (2008) Flavor formation and character in cocoa and chocolate: a critical review. Crit Rev Food Sci Nutr 48(9):840–857
Afoakwa EO, Paterson A, Fowler M, Ryan A (2009) Matrix effects on flavour volatiles release in dark chocolates varying in particle size distribution and fat content using GC–mass spectrometry and GC–olfactometry. Food Chem 113(1):208–215
Antoce AO (2012) Study of the possibility of discrimination by an electronic nose of Feteasca regala wines produced with neutral and aromatic yeasts. Scientific Papers Series B Horticulture
Antoce AO, Namolosanu IOAN (2011) Rapid and precise discrimination of wines by means of an electronic nose based on gas-chromatography. Rev Chim 62(6):593–595
Aprotosoaie AC, Luca SV, Miron A (2016) Flavor chemistry of cocoa and cocoa products—an overview. Compr Rev Food Sci Food Saf 15(1):73–91
Banerjee R, Tudu B, Bandyopadhyay R, Bhattacharyya N (2016) A review on combined odor and taste sensor systems. J Food Eng 190:10–21
Beckett ST (2009) Industrial chocolate manufacture and use. Blackwell, Oxford, UK
Caligiani A, Cirlini M, Palla G, Ravaglia R, Arlorio M (2007) GC-MS detection of chiral markers in cocoa beans of different quality and geographic origin. Chirality 19(4):329–334
Caligiani A, Marseglia A, Prandi B, Palla G, Sforza S (2016) Influence of fermentation level and geographical origin on cocoa bean oligopeptide pattern. Food Chem 211:431–439
Cambrai A, Marcic C, Morville S, Sae Houer P, Bindler F, Marchioni E (2010) Differentiation of chocolates according to the cocoa's geographical origin using chemometrics. J Agric Food Chem 58(3):1478–1483
CAOBISCO/ECA/FCC (2015) Cocoa beans: chocolate and cocoa industry quality requirements. In: End MJ, Dand R (eds). September 2015
Chatterjee D, Bhattacharjee P, Lechat H, Ayouni F, Vabre V (2012) Assessment of shelf-life of cookies formulated with clove extracts using electronic nose. In: Sixth international conference on sensing technology. IEEE, United States, New York, p 404–409
Cheng H, Qin ZH, Guo XF, Hu XS, Wu JH (2013) Geographical origin identification of propolis using GC–MS and electronic nose combined with principal component analysis. Food Res Int 51(2):813–822
Compagnone D, Faieta M, Pizzoni D, Di Natale C, Paolesse R, Van Caelenberg T, Beheydt B, Pittia P (2015) Quartz crystal microbalance gas sensor arrays for the quality control of chocolate. Sensors Actuators B Chem 207:1114–1120
Counet C, Callemien D, Ouwerx C, Collin S (2002) Use of gas chromatography−olfactometry to identify key odorant compounds in dark chocolate. Comparison of samples before and after Conching. J Agric Food Chem 50(8):2385–2391
Counet C, Ouwerx C, Rosoux D, Collin S (2004) Relationship between procyanidin and flavor contents of cocoa liquors from different origins. J Agric Food Chem 52(20):6243–6249
Frauendorfer F, Schieberle P (2006) Identification of the key aroma compounds in cocoa powder based on molecular sensory correlations. J Agric Food Chem 54(15):5521–5529
Frauendorfer F, Schieberle P (2008) Changes in key aroma compounds of Criollo cocoa beans during roasting. J Agric Food Chem 56(21):10244–10251
Gan Z, Yang Y, Li J, Wen X, Zhu M, Jiang Y, Ni Y (2016) Using sensor and spectral analysis to classify botanical origin and determine adulteration of raw honey. J Food Eng 178:151–158
Gliszczyńska-Świgło A, Chmielewski J (2017) Electronic nose as a tool for monitoring the authenticity of food. A review. Food Anal Methods 10(6):1800–1816
Górska-Horczyczak E, Wojtasik-Kalinowska I, Guzek D, Sun DW, Wierzbicka A (2017) Differentiation of chill-stored and frozen pork necks using electronic nose with ultra-fast gas chromatography. J Food Process Eng 40(5):e12540
Gu F, Tan L, Wu H, Fang Y, Xu F, Chu Z, Wang Q (2013) Comparison of cocoa beans from China, Indonesia and Papua New Guinea. Foods 2:183–197
Gutierrez J, Horrillo MC (2014) Advances in artificial olfaction: sensors and applications. Talanta 124:95–105
Hashim L, Plumas B (1999) Electronic nose for monitoring cocoa beans aroma. In: Hurst J (ed) Electronic noses and sensor array based systems-design and applications. Technomic Publishing Co, Inc., Lancaster, pp 296–307
Hernández C, Rutledge D (1994) Multivariate statistical analysis of gas chromatograms to differentiate cocoa masses by geographical origin and roasting conditions. Analyst 119(6):1171–1176
ICCO (2016) ICCO Panel recognizes 23 countries as fine and flavour cocoa exporters. https://www.icco.org/about-us/icco-news/319-icco-panel-recognizes-23-countries-as-fine-and-flavour-cocoa-exporters.html. Accessed 25 June 2018
Jinap S, Dimick PS, Hollender R (1995) Flavour evaluation of chocolate formulated from beans from different countries. Food Control 6(2):105–110
Kongor JE, Hinneh M, de Walle DV, Afoakwa EO, Boeckx P, Dewettinck K (2016) Factors influencing quality variation in cocoa (Theobroma cacao) bean flavour profile—a review. Food Res Int 82:44–52
Lefeber T, Janssens M, Moens F, Gobert W, De Vuyst L (2011) Interesting starter culture strains for controlled cocoa bean fermentation revealed by simulated cocoa pulp fermentations of cocoa-specific lactic acid bacteria. Appl Environ Microbiol 77(18):6694–6698
Liu J, Liu M, He C, Song H, Guo J, Wang Y, Yang H, Su X (2015) A comparative study of aroma-active compounds between dark and milk chocolate: relationship to sensory perception. J Sci Food Agric 95(6):1362–1372
Loutfi A, Coradeschi S, Mani GK, Shankar P, Rayappan JBB (2015) Electronic noses for food quality: a review. J Food Eng 144:103–111
Luna F, Crouzillat D, Cirou L, Bucheli P (2002) Chemical composition and flavor of Ecuadorian cocoa liquor. J Agric Food Chem 50:3527–3532
Luykx DM, Van Ruth SM (2008) An overview of analytical methods for determining the geographical origin of food products. Food Chem 107(2):897–911
Marion B, Herve L, Fatma A (2011) Rancidity control of nut mixtures using an electronic nose. Focus Food Anal 22:12–15
Melucci D, Bendini A, Tesini F, Barbieri S, Zappi A, Vichi S, Conte L, Toschi TG (2016) Rapid direct analysis to discriminate geographic origin of extra virgin olive oils by flash gas chromatography electronic nose and chemometrics. Food Chem 204:263–273
Muhammad DRA, Saputro AD, Rottiers H, Van de Walle D, Dewettinck K (2018) Physicochemical properties and antioxidant activities of chocolates enriched with engineered cinnamon nanoparticles. Eur Food Res Technol 1–18
Olunloyo VOS, Ibidapo TA, Dinrifo RR (2011) Neural network-based electronic nose for cocoa beans quality assessment. Agric Eng Int CIGR J 13(4)
Peng Q, Tian R, Chen F, Li B, Gao H (2015) Discrimination of producing area of Chinese Tongshan Kaoliang spirit using electronic nose sensing characteristics combined with the chemometrics methods. Food Chem 178:301–305
Peris M, Escuder-Gilabert L (2009) A 21st century technique for food control: electronic noses. Anal Chim Acta 638(1):1–15
Peris M, Escuder-Gilabert L (2016) Electronic noses and tongues to assess food authenticity and adulteration. Trends Food Sci Technol 58:40–54
Ramli N, Hassan O, Said M, Samsudin W, Idris NA (2006) Influence of roasting conditions on volatile flavor of roasted Malaysian cocoa beans. J Food Process Preserv 30(3):280–298
Reineccius G, Heath H (2008) Flavor chemistry and technology. 2006. Taylor & Francis Group, New York
Rodriguez-Campos J, Escalona-Buendía HB, Orozco-Avila I, Lugo-Cervantes E, Jaramillo-Flores ME (2011) Dynamics of volatile and non-volatile compounds in cocoa (Theobroma cacao L.) during fermentation and drying processes using principal components analysis. Food Res Int 44(1):250–258
Rottiers H, Everaert H, Boeckx P, Limba G, Baert G, De Wever J, Maebe K, Smagghe G, Dewettinck K, Messens K (2018) Unraveling the genetic background of the Yangambi research center cacao germplasm collection, DR Congo. Tree Genet Genomes 14(5):68
Saltini R, Akkerman R, Frosch S (2013) Optimizing chocolate production through traceability: a review of the influence of farming practices on cocoa bean quality. Food Control 29(1):167–187
Schaller E, Bosser JO, Escher F (1998) Electronic noses’ and their application to food. LWT-Food Sci Technol 31(4):305–316
Schwan RF, Wheals AE (2004) The microbiology of cocoa fermentation and its role in chocolate quality. Crit Rev Food Sci Nutr 44(4):205–221
Śliwińska M, Wiśniewska P, Dymerski T, Wardencki W, Namieśnik J (2016a) Application of electronic nose based on fast GC for authenticity assessment of polish homemade liqueurs called Nalewka. Food Anal Methods 9(9):2670–2681
Śliwińska M, Wiśniewska P, Dymerski T, Wardencki W, Namieśnik J (2016b) Evaluation of the suitability of electronic nose based on fast GC for distinguishing between the plum spirits of different geographical origins. Eur Food Res Technol 242(11):1813–1819
Smit G, Smit BA, Engels WJ (2005) Flavour formation by lactic acid bacteria and biochemical flavour profiling of cheese products. FEMS Microbiol Rev 29(3):591–610
Sukha DA, Butler DR, Umaharan P, Boult E (2008) The use of an optimised organoleptic assessment protocol to describe and quantify different flavour attributes of cocoa liquors made from Ghana and Trinitario beans. Eur Food Res Technol 226(3):405–413
Teye E, Huang X, Dai H, Chen Q (2013) Rapid differentiation of Ghana cocoa beans by FT-NIR spectroscopy coupled with multivariate classification. Spectrochim Acta A Mol Biomol Spectrosc 114:183–189
Torres-Moreno M, Tarrega A, Costell E, Blanch C (2012) Dark chocolate acceptability: influence of cocoa origin and processing conditions. J Sci Food Agric 92(2):404–411
Tran PD, Van de Walle D, De Clercq N, De Winne A, Kadow D, Lieberei R, Messens K, Tran DN, Dewettinck K, Van Durme J (2015) Assessing cocoa aroma quality by multiple analytical approaches. Food Res Int 77:657–669
Valdez LF, Gutierrez JM (2016) Chocolate classification by an electronic nose with pressure controlled generated stimulation. Sensors 16(10):1745
Werlein HD (2001) Discrimination of chocolates and packaging materials by an electronic nose. Eur Food Res Technol 212(4):529–533
Wiśniewska P, Śliwińska M, Dymerski T, Wardencki W, Namieśnik J (2015) Differentiation between spirits according to their botanical origin. Food Anal Methods 9(4):1029–1035
Wiśniewska P, Śliwińska M, Namieśnik J, Wardencki W, Dymerski T (2016) The verification of the usefulness of electronic nose based on ultra-fast gas chromatography and four different chemometric methods for rapid analysis of Spirit beverages. J Anal Methods Chem
Wojnowski W, Majchrzak T, Dymerski T, Gębicki J, Namieśnik J (2017) Poultry meat freshness evaluation using electronic nose technology and ultra-fast gas chromatography. Monatsh Chem 148(9):1631–1637
Xiao ZB, Yu D, Niu YW, Chen F, Song SQ, Zhu JC, Zhu GY (2014) Characterization of aroma compounds of Chinese famous liquors by gas chromatography-mass spectrometry and flash GC electronic-nose. J Chromatogr B Anal Technol Biomed Life Sci 945:92–100
Yimenu SM, Kim JY, Kim BS (2017) Prediction of egg freshness during storage using electronic nose. Poult Sci 96(10):3733–3746
Yoshida K, Ishikawa E, Joshi M, Lechat H, Ayouni F, Bonnefille M (2012) Profiling scotch malt whisky spirits from different distilleries using an electronic nose and an expert sensory panel. In: Perception and machine intelligence. Springer, Berlin, p 155–162
Ziegleder G (2009) Flavour development in cocoa and chocolate. In: Beckett ST (ed) Industrial chocolate manufacture and use, 4th edn. Blackwell Publishing, Oxford, pp 169–191
Acknowledgments
The authors would like to thank CacaoLab (Ghent Belgium), Cimarron Cocoa Estates (Ecuador), Candy Ruiz (Peru), Fondo Nacional del cacao (FEDECACAO, Colombia), Luciana Monteiro and Marcello Ortolano (Brazil), Esco Kivu Sprl (Congo), Dr. Phuoc Hong Duc Pham and Dr. Tăng Kim Hồng from Center for Forestry Research and Technology Transfer (CEFFORT), Nong Lam University (NLU) (Vietnam), Consolidated Agriventures Corp. (AGCOR) and Joel Juvinal (Philippines) for providing the cocoa bean samples. Further, we are grateful to Katharina Riehn, Christina Krabbe, and Stephanie Nottelmann from Group Hamburg University of Applied Sciences, Hamburg, Germany for technical assistance during cocoa liquor production.
Funding
Financial support for this research was obtained from BOF (Special Research Fund) of Ghent University (PhD grant). BOF is further recognized for its financial support in the acquisition of the Heracles II GC E-nose (grant nr. BOF 01B05915).
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of Interest
Hayley Rottiers declares that she has no conflict of interest. Daylan Amelia Tzompa Sosa declares that she has no conflict of interest. Liesbet Van de Vyver declares that she has no conflict of interest. Michael Hinneh declares that he has no conflict of interest. Helena Everaert declares that she has no conflict of interest. Jocelyn De Wever declares that she has no conflict of interest. Kathy Messens declares that she has no conflict of interest. Koen Dewettinck declares that he has no conflict of interest.
Ethical Approval
This article does not contain any studies with human participants or animals performed by any of the authors.
Informed Consent
Not applicable.
Electronic Supplementary Material
ESM 1
(DOCX 158 kb)
Rights and permissions
About this article
Cite this article
Rottiers, H., Tzompa Sosa, D.A., Van de Vyver, L. et al. Discrimination of Cocoa Liquors Based on Their Odor Fingerprint: a Fast GC Electronic Nose Suitability Study. Food Anal. Methods 12, 475–488 (2019). https://doi.org/10.1007/s12161-018-1379-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12161-018-1379-7