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Aims: Free fatty acids (FFA) result from hydrolysis of cocoa butter triacylglycerides due to various abiotic and biotic factors. The resurgence of high FFA contents above 1.75% in cocoa beans depended on Ivorian geographical origin. High FFA contents have become a serious quality problem because they induced serious consequences for some beneficial properties of cocoa butter and chocolate. This study investigated the improvement of quality of Ivorian cocoa beans by reducing their FFA contents. Methodology: Samples: 240 cocoa beans batches were sampled from cocoa farmers of some big cocoa producing regions for their FFA contents analysis. Also, influence of primary post-harvest processing such as pod's sanitary status, pod opening delay, fermentation duration and dry cocoa beans storage under various relative humidity (RH) ranged 80-90% on FFA's formation of Ivorian cocoa beans was investigated. Data interpretations were performed according to the Fisher's test. Results: Main results showed that dry cocoa beans recorded FFA content varying from 0.99 to 14% in function of the geographical origin. Beside, 53% of tested cocoa bean samples exhibited FFA content up to 1.75%. Poor sanitary status of pods and 7-days fermented cocoa beans recorded FFA content above 1.75%. Dry cocoa beans stored at RH above 85% promoted more the FFA's formation (14%) than those stored under lower RH values. 53% of tested cocoa beans samples presented FFA contents up to 1.75%. Controlled primary post-harvest processing highlighted that poor sanitary status of pods, 7-days fermentation and storage of dry cocoa beans at RH above 85% lead to FFA content above 1.75%. Conclusion: So, in order to produce fermented and dried cocoa beans containing a suitable FFA content in the context of climate change, mitigation strategies need to integrate good crop conditions regarding postharvest processing and to improve beneficial ones.

Aims: This study aimed to determine influence of post-harvest treatments on PAH's formation in raw cocoa. Study Design: A total of 370 samples were analyzed during 2014 and 2015 cocoa harvesting. Methodology: A method based on a solid-liquid and liquid-liquid extraction followed by an HPLC- Fluorescence assay was optimized and validated for PAHs analysis in cocoa. Results: Whatever the post-harvest treatment, cocoa PAH's contents were under 6.19 ± 0.30.

Cocoa pod-opening delay and bean fermentation promote the organoleptic quality of chocolate. The present research investigated the changes in the volatile fingerprint of cocoa harvested at a traditional plantation. Cocoa beans extracted from 2-days pod-opening delay were simultaneously fermented for 5 days using container and then sun-dried to 7–8% moisture content at five different locations: Akoupé, San Pedro, Soubré, Djekanou and Daloa. The aromatic analysis were done on cocoa using the HS-SPME-GC/MS technique. Professional panelists evaluated the sensory perceptions of the chocolate. The results shows that cocoa fermented in both Daloa and Soubré regions were differentiated by 2,3-butanediol while those processed in other regions presented highest acetoin content. However, fermented cocoa from Soubré region exhibited most amount of 2,3-butanediol, diacetate A whereas 2,3,5,6-tetramethylpyrazine differentiated those from Daloa region. Sensory properties of chocolate were not linked to the aromatic compound precursors profile of beans. The fermentation performed in San Pédro region promote both the generation of more desirable aromatic compounds of cocoa and sensory attributes of the finished chocolate. The fermentation location generates a greater differentiation of the volatile fingerprint of cocoa and the sensory perceptions of the finished chocolate.

Cocoa pod-opening delay and bean fermentation promote the organoleptic quality of chocolate. The present research investigated the changes in the volatile fingerprint of cocoa harvested at a traditional plantation. Cocoa beans extracted from 2-days pod-opening delay were simultaneously fermented for 5 days using container and then sun-dried to 7–8% moisture content at five different locations: Akoupé, San Pedro, Soubré, Djekanou and Daloa. The aromatic analysis were done on cocoa using the HS-SPME-GC/MS technique. Professional panelists evaluated the sensory perceptions of the chocolate. The results shows that cocoa fermented in both Daloa and Soubré regions were differentiated by 2,3-butanediol while those processed in other regions presented highest acetoin content. However, fermented cocoa from Soubré region exhibited most amount of 2,3-butanediol, diacetate A whereas 2,3,5,6-tetramethylpyrazine differentiated those from Daloa region. Sensory properties of chocolate were not linked to the aromatic compound precursors profile of beans. The fermentation performed in San Pédro region promote both the generation of more desirable aromatic compounds of cocoa and sensory attributes of the finished chocolate. The fermentation location generates a greater differentiation of the volatile fingerprint of cocoa and the sensory perceptions of the finished chocolate.

The aromatic quality of chocolate requires the use of cocoa with high aromatic potential, this being acquired during the fermentation of cocoa beans. Traditional fermentation is still often carried out on a small scale with wild strains of yeasts and acetic bacteria and under poorly controlled conditions leading to cocoa quality ranging from best to worst. This study is the first part of a project aiming to control quality of cocoa to produce high aromatic quality chocolate by using a mixed starter of selected strains of yeast and acetic bacteria and by controlling the conditions of fermentation. To achieve this objective, a mathematical model of the alcoholic fermentation of cocoa beans has been developed. The growth, glucose consumption and ethanol production of Saccharomyces cerevisiae LM strain in synthetic broth were modeled for the most important intrinsic (pH, glucose, ethanol, free nitrogen and oxygen levels) and extrinsic (temperature, oxygen level) fermentation parameters. The model was developed by combining the effects of individual conditions in a multiplicative way using the gamma concept. The model was validated in liquid synthetic medium at two different inoculation levels 104 and 106 CFU/mL with an increase in temperature that recorded during spontaneous fermentations. The model clearly shows that the level of inoculation and the speed of the increase in temperature clearly drive yeast growth, while other factors including pH and ethanol, free nitrogen and oxygen levels have no significant impact on yeast growth.

Le cacao est la 3ème denrée la plus commercialisée dans le monde et 23 pays sont classés selon l'ICCO comme producteurs de cacao fin, dont Madagascar. Le cacao de Madagascar est classé cacao fin à 100 % selon l'ICCO. Il est un des plus réputés au monde, même s'il ne représente que 0,2 % de la production mondiale. Peu d'études existent concernant la caractérisation du cacao malgache et sa fermentation. La fermentation est une étape post-récolte pour l'obtention des caractéristiques aromatiques et sensorielles d'un cacao de qualité. Ce travail a permis de déterminer les critères de qualité et de suivre les évolutions des critères organoleptiques, de la composition volatile et les micro-organismes au cours de la fermentation. Le cacao produit à Madagascar appartient principalement aux variétés Criollo et Trinitario. Le suivi de la fermentation montre qu'au niveau sensoriel, les descripteurs " végétal, terreux, astringent, amer " des fèves de cacao non ou peu fermentées (24-48 h) s'estompent pour laisser place aux descripteurs cacao, chocolat, fruité, acide pour des fèves de cacao en fin de fermentation (96 h-144 h). De même, les teneurs en composés volatils liés aux descripteurs sensoriels recherchés tels que l'acétate de 3-méthylbutyle, l'acétate d'éthyle, le benzaldéhyde, la tétraméthylpyrazine, l'acide acétique augmentent au cours de la fermentation. L'étude de la flore microbienne a permis d'identifier l'origine de la production de certains composés volatils. Notamment, la levure Hanseniaspora opuntiae présente un intérêt particulier car elle est associée à la production de 2-phényléthanol. L'étude des communautés levuriennes par voie moléculaire a confirmé la présence des levures isolées et a mis en évidence d'autres souches notamment du genre Pichia qui sont aussi productrices de molécules volatiles telles que l'acétate de 2-phényléthyle et l'acétate d'éthyle.

The average weight of cocoa beans is not generally taken into account during breeding processes, although it is a trait of interest. Several studies indicate that the weight of the beans has a high heritability in Theobroma cacao. However, the values obtained from different countries for the same clone often vary. In this study, we analyzed the effect of different factors on the weight of the beans. Apart from the clone effect, three main factors had an impact: i) the number of beans per pod: a good filling of the pod with beans tended to limit the weight of the beans, ii) the position of the beans in the pod: beans in the apical part of the pod were significantly lighter than the others and iii) the longer the duration of the fructification cycle the heavier the beans were (positive genetics correlation). These results lead us to propose protocols aimed at normalizing the phenotypic values of the genetic material. To obtain a reliable estimate of the bean weight, the following is proposed: either to use beans obtained from manual pollination to saturate the pods with beans, or to systematically use the number beans in the pods as a covariable.

Given the persistent poor livelihood of cocoa-farming households, future climate predictions and the worldwide demand pressure for higher cocoa quality and productivity, there is still a strong need to find new approaches that guarantee a sustainable cocoa future in cocoa-producing countries amongst which Cameroon is one of them. This exploratory research investigates potential future pathways for the cocoa sector in Cameroon by mapping the perceptions of actors involved in the socio-technical regime. Qualitative expert interviews, structured questionnaires and field observation, as well as a focus group discussion have been applied to understand how a sustainability transition can be triggered. The study shows that actors envisage a sustainability change which determines their actions; however, their perceptions towards future transitions are not actively coordinated. Actors are not finding a way of adopting new organizational structures and letting a transition occur effectively, like in the case of certification standards. An alignment of perceptions and activities, and a stronger cooperation between the private and public are strongly recommended. The study encourages to consider a coordination of actors' perceptions towards future scenarios as a starting point to study sustainability transitions.

Chocolate is a widely consumed product worldwide due to its exquisite flavor, which comes from the unique and fascinating cocoa flavor. This flavor depends on little controllable variables such as the genotype and the agroecological niche, and on the other side, on postharvest operations: (1) cocoa transformation from seeds to beans that comprises cocoa seeds preconditioning, fermentation, and drying, and (2) the production of chocolate from the bean in which roasting is highlighted. Postharvest transformation operations are critically important because during these, cocoa flavor is formed, allowing the differentiation of two categories: bulk and specialty cocoa. In this sense, this article presents an overview of cocoa postharvest operations, the variables and phenomena that influence and control the physical and biochemical transformation from seeds to cocoa beans, and their relation to the formation of chocolate flavor. Moreover, research perspectives in terms of control and management of postharvest practices in order to obtain cocoa with differentiated and specialty characteristics “from bean to bar” are discussed.

A large fraction of the South-American cacao production is affected by new cadmium (Cd) regulations in cacao. This work was set up to characterize the distribution and speciation of Cd within the cacao fruit and to monitor potential Cd redistribution during cacao fermentation. In cacao fruits from four locations, Cd concentrations decreased with testa > nib ∼placenta ∼pod husk > mucilage. The distribution of Cd within cacao beans was successfully visualized using laser ablation inductively coupled plasma spectrometry (LA-ICP-MS) and confirmed higher Cd concentrations in the testa than in the nib. Speciation analysis by X-ray absorption spectroscopy (XANES) of unfermented cacao beans revealed that Cd was bound to O/N-ligands in both nib and testa. Fermentation induced an outward Cd migration from the nibs to the testa, i.e. against the total concentration gradient. This migration occurred only if the fermentation was sufficiently extensive to decrease the pH in the nib to <5.0, likely as a result of increased Cd mobility due to organic acid penetration into the nibs. The change in dry weight based nib Cd concentrations during fermentation was, on average, a factor 1.3 decrease. We propose that nib Cd can be reduced if the nib pH is sufficiently acidified during fermentation. However, a balance must be found between flavor development and Cd removal since extreme acidity is detrimental for cacao flavor.

A large fraction of the South-American cacao production is affected by new cadmium (Cd) regulations in cacao. This work was set up to characterize the distribution and speciation of Cd within the cacao fruit and to monitor potential Cd redistribution during cacao fermentation. In cacao fruits from four locations, Cd concentrations decreased with testa > nib ∼placenta ∼pod husk > mucilage. The distribution of Cd within cacao beans was successfully visualized using laser ablation inductively coupled plasma spectrometry (LA-ICP-MS) and confirmed higher Cd concentrations in the testa than in the nib. Speciation analysis by X-ray absorption spectroscopy (XANES) of unfermented cacao beans revealed that Cd was bound to O/N-ligands in both nib and testa. Fermentation induced an outward Cd migration from the nibs to the testa, i.e. against the total concentration gradient. This migration occurred only if the fermentation was sufficiently extensive to decrease the pH in the nib to <5.0, likely as a result of increased Cd mobility due to organic acid penetration into the nibs. The change in dry weight based nib Cd concentrations during fermentation was, on average, a factor 1.3 decrease. We propose that nib Cd can be reduced if the nib pH is sufficiently acidified during fermentation. However, a balance must be found between flavor development and Cd removal since extreme acidity is detrimental for cacao flavor.

The average weight of cocoa beans is not generally taken into account during breeding processes, although it is a trait of interest. Several studies indicate that the weight of the beans has a high heritability in Theobroma cacao. However, the values obtained from different countries for the same clone often vary. In this study, we analyzed the effect of different factors on the weight of the beans. Apart from the clone effect, three main factors had an impact: i) the number of beans per pod: a good filling of the pod with beans tended to limit the weight of the beans, ii) the position of the beans in the pod: beans in the apical part of the pod were significantly lighter than the others and iii) the longer the duration of the fructification cycle the heavier the beans were (positive genetics correlation). These results lead us to propose protocols aimed at normalizing the phenotypic values of the genetic material. To obtain a reliable estimate of the bean weight, the following is proposed: either to use beans obtained from manual pollination to saturate the pods with beans, or to systematically use the number beans in the pods as a covariable.

Given the persistent poor livelihood of cocoa-farming households, future climate predictions and the worldwide demand pressure for higher cocoa quality and productivity, there is still a strong need to find new approaches that guarantee a sustainable cocoa future in cocoa-producing countries amongst which Cameroon is one of them. This exploratory research investigates potential future pathways for the cocoa sector in Cameroon by mapping the perceptions of actors involved in the socio-technical regime. Qualitative expert interviews, structured questionnaires and field observation, as well as a focus group discussion have been applied to understand how a sustainability transition can be triggered. The study shows that actors envisage a sustainability change which determines their actions; however, their perceptions towards future transitions are not actively coordinated. Actors are not finding a way of adopting new organizational structures and letting a transition occur effectively, like in the case of certification standards. An alignment of perceptions and activities, and a stronger cooperation between the private and public are strongly recommended. The study encourages to consider a coordination of actors' perceptions towards future scenarios as a starting point to study sustainability transitions.

Les exigences européennes sur la qualité du cacao conduisent au développement de la certification, pour améliorer la production et la gestion post-récolte des fèves. Cependant, la certification reste peu développée au Cameroun. Cet article mobilise le modèle de la transition sociotechnique pour analyser les déterminants d'adoption de la certification. Des entretiens auprès de 11 acteurs de la filière cacao ont été menés, ainsi qu'une enquête auprès de 90 producteurs. Les résultats mettent en exergue l'incomplétude du système acteur de la certification, qui se traduit par sa faible diffusion. Cette tendance est accentuée par l'absence d'un différentiel de prix aux producteurs entre cacao certifié et cacao ordinaire. La conclusion interroge la capacité des normes de certification à transformer le secteur cacao.

Cocoa quality depends on several parameters, such as cocoa variety, environmental growth conditions, cultivation technique, and post-harvest treatments applied to coca beans. In this work, we studied the impact of cocoa post-harvest processing on both microbial communities structure and volatile composition. Cocoa beans samples were fermented in wooden boxes in Ivory Coast at different time intervals with turning and without turning, and derived from pods stored for two different duration times. Cocoa beans were analyzed using a molecular fingerprinting method (PCR-DGGE) in order to detect variations in microbial communities' structure; this global analysis was coupled to SPME-GC–MS for assessing cocoa volatile profiles. The results showed that the main parameter that influenced microbial communities structure was fermentation time, followed by turning, whereas, pods storage duration had a minor impact. Similar results were obtained for aromatic profile, except for pods storage duration that significantly affected volatile compound production. Global statistical analysis using Canonical Correspondence Analysis (CCA), showed the relationship between microbial communities and volatile composition. Furthermore, this study allowed the identification of discriminating microbial and chemical markers of cocoa post-harvest processing.

Cocoa quality depends on several parameters, such as cocoa variety, environmental growth conditions, cultivation technique, and post-harvest treatments applied to coca beans. In this work, we studied the impact of cocoa post-harvest processing on both microbial communities structure and volatile composition. Cocoa beans samples were fermented in wooden boxes in Ivory Coast at different time intervals with turning and without turning, and derived from pods stored for two different duration times. Cocoa beans were analyzed using a molecular fingerprinting method (PCR-DGGE) in order to detect variations in microbial communities' structure; this global analysis was coupled to SPME-GC–MS for assessing cocoa volatile profiles. The results showed that the main parameter that influenced microbial communities structure was fermentation time, followed by turning, whereas, pods storage duration had a minor impact. Similar results were obtained for aromatic profile, except for pods storage duration that significantly affected volatile compound production. Global statistical analysis using Canonical Correspondence Analysis (CCA), showed the relationship between microbial communities and volatile composition. Furthermore, this study allowed the identification of discriminating microbial and chemical markers of cocoa post-harvest processing.

Les exigences européennes sur la qualité du cacao conduisent au développement de la certification, pour améliorer la production et la gestion post-récolte des fèves. Cependant, la certification reste peu développée au Cameroun. Cet article mobilise le modèle de la transition sociotechnique pour analyser les déterminants d'adoption de la certification. Des entretiens auprès de 11 acteurs de la filière cacao ont été menés, ainsi qu'une enquête auprès de 90 producteurs. Les résultats mettent en exergue l'incomplétude du système acteur de la certification, qui se traduit par sa faible diffusion. Cette tendance est accentuée par l'absence d'un différentiel de prix aux producteurs entre cacao certifié et cacao ordinaire. La conclusion interroge la capacité des normes de certification à transformer le secteur cacao.

The fine-flavor cocoa industry explores mainly six chocolate sensory traits from four traditional cocoa (Theobroma cacao L.) varieties. The importance of cocoa pulp flavors and aromas has been ignored until we recently showed that they migrate into beans and into chocolates. Pulp sensory traits are strongly genotype dependent and correlated to human preference. Growers of the native Chuncho variety from Cusco, Peru, which is the cocoa that the Incas consumed, make pulp juices from preferred trees (genotypes). Evaluations of 226 preferred trees evidenced presence of 64 unique mostly multi-trait sensory profiles. Twenty nine of the 40 flavors and aromas identified mimic those of known fruit and flower or spice species such as mandarin, soursop, custard apple, cranberry, peach, banana, inga, mango, nut, mint, cinnamon, jasmine, rose and lily. Such large sensory diversity and mimicry is unknown in other commercial fleshy fruit species. So far, 14 Chuncho-like pulp sensory traits have been identified among different cocoa varieties elsewhere suggesting that Chuncho is part of the “centre of origin” for cocoa flavors and aromas. Stable expression of multi-trait Chuncho sensory profiles suggest pleiotropic dominant inheritance, favoring selection for quality traits, which is contrasting with the complex sensory trait determination in other fleshy fruit species. It is inferred that the large sensory diversity of Chuncho cocoa can only be explained by highly specialized sensory trait selection pressure exerted by frugivores, during evolution, and by the indigenous “Matsigenkas”, during domestication. Chuncho beans, still largely employed as a bulk cocoa source, deserve to become fully processed as an extra-fine cocoa variety. The valorization of the numerous T. cacao sensory profiles in chocolates, raw beans and juices should substantially diversify and boost the fineflavor cocoa industry, this time based on the Matsigenka/Inca and not anymore on the Maya cocoa traditions.

Les cacaoyères continuent de s'étendre et de remplacer les dernières forêts du pays. La décennie de crise politico-militaire en a prolongé le processus au dépend des aires protégées, contribuant à la chute du cours mondial en 2017. Simultanément, la Côte d'Ivoire perd sa " rente forêt ". Les coûts de production du cacao augmentent. Face aux changements écologiques, climatiques, techniques, sociaux et politiques associés à ces cycles du cacao, comment l'agriculture familiale innove et transforme+ elle les paysages, avec ou sans cacao ? Ces questions sont traitées empiriquement sur des échantillons de 40 à 200 exploitations sur 10 sites de la zone cacaoyère, faisant le point sur les changements techniques dans le contexte écologique et social mouvementé des décades 2000 et 2010. Les résultats se structurent en une " hexalogie " de dynamiques, résultante des interactions entre déroulement du cycle du cacao, prix, réseaux migratoires, crise politico-militaire et changement climatique, s'appliquant inégalement selon les régions. La diversification ou la reconversion du cacao vers l'anacarde, le développement des élevages et l'adoption de la fumure animale, contribuant à doubler les rendements des cacaoyères, démontre la capacité de l'agriculture familiale à innover plus efficacement que les structures publiques et privées. Mais comme tout progrès technique, ces innovations peuvent aussi contribuer à la chute du cours mondial.

The fine-flavor cocoa industry explores mainly six chocolate sensory traits from four traditional cocoa (Theobroma cacao L.) varieties. The importance of cocoa pulp flavors and aromas has been ignored until we recently showed that they migrate into beans and into chocolates. Pulp sensory traits are strongly genotype dependent and correlated to human preference. Growers of the native Chuncho variety from Cusco, Peru, which is the cocoa that the Incas consumed, make pulp juices from preferred trees (genotypes). Evaluations of 226 preferred trees evidenced presence of 64 unique mostly multi-trait sensory profiles. Twenty nine of the 40 flavors and aromas identified mimic those of known fruit and flower or spice species such as mandarin, soursop, custard apple, cranberry, peach, banana, inga, mango, nut, mint, cinnamon, jasmine, rose and lily. Such large sensory diversity and mimicry is unknown in other commercial fleshy fruit species. So far, 14 Chuncho-like pulp sensory traits have been identified among different cocoa varieties elsewhere suggesting that Chuncho is part of the “centre of origin” for cocoa flavors and aromas. Stable expression of multi-trait Chuncho sensory profiles suggest pleiotropic dominant inheritance, favoring selection for quality traits, which is contrasting with the complex sensory trait determination in other fleshy fruit species. It is inferred that the large sensory diversity of Chuncho cocoa can only be explained by highly specialized sensory trait selection pressure exerted by frugivores, during evolution, and by the indigenous “Matsigenkas”, during domestication. Chuncho beans, still largely employed as a bulk cocoa source, deserve to become fully processed as an extra-fine cocoa variety. The valorization of the numerous T. cacao sensory profiles in chocolates, raw beans and juices should substantially diversify and boost the fineflavor cocoa industry, this time based on the Matsigenka/Inca and not anymore on the Maya cocoa traditions.

Les cacaoyères continuent de s'étendre et de remplacer les dernières forêts du pays. La décennie de crise politico-militaire en a prolongé le processus au dépend des aires protégées, contribuant à la chute du cours mondial en 2017. Simultanément, la Côte d'Ivoire perd sa " rente forêt ". Les coûts de production du cacao augmentent. Face aux changements écologiques, climatiques, techniques, sociaux et politiques associés à ces cycles du cacao, comment l'agriculture familiale innove et transforme+ elle les paysages, avec ou sans cacao ? Ces questions sont traitées empiriquement sur des échantillons de 40 à 200 exploitations sur 10 sites de la zone cacaoyère, faisant le point sur les changements techniques dans le contexte écologique et social mouvementé des décades 2000 et 2010. Les résultats se structurent en une " hexalogie " de dynamiques, résultante des interactions entre déroulement du cycle du cacao, prix, réseaux migratoires, crise politico-militaire et changement climatique, s'appliquant inégalement selon les régions. La diversification ou la reconversion du cacao vers l'anacarde, le développement des élevages et l'adoption de la fumure animale, contribuant à doubler les rendements des cacaoyères, démontre la capacité de l'agriculture familiale à innover plus efficacement que les structures publiques et privées. Mais comme tout progrès technique, ces innovations peuvent aussi contribuer à la chute du cours mondial.

Depuis plusieurs années, les programmes de recherche chez le cacaoyer ont mis l'accent sur l'étude des bases génétiques des caractères agronomiques d'intérêt, notamment concernant la résistance aux maladies et la qualité des fèves de cacao, qui représentent deux attributs importants pour la cacaoculture et la production de chocolat. Ce travail présente, par l'exploration du transcriptome et du génome du cacaoyer, la constitution de ressources moléculaires et l'analyse des voies de biosynthèse impliquées dans plusieurs de ces caractères agronomiques d'intérêt. L'étude du transcriptome a permis l'identification de plusieurs dizaines de milliers de gènes exprimés dans divers organes et pour différentes conditions environnementales et ont fourni de nombreux marqueurs moléculaires qui ont été utilisés pour réaliser des cartes génétiques haute densité. Les informations apportées par ce travail ont permis d'engager le séquençage du génome de la variété Criollo du cacaoyer. Son analyse et son annotation ont apporté un ensemble d'informations biologiques cruciales, depuis le catalogue des gènes et éléments mobiles jusqu'aux aspects évolutifs qui a révélé une structure du génome peu remanié par rapport à l'ancêtre commun aux dicotylédones. Par la suite, les travaux que nous avons menés pour améliorer la séquence complète ont conduit à une réduction considérable de la fragmentation chromosomique observée dans la première version. Par ailleurs 97% de la séquence assemblée et 99% des gènes sont désormais ancrés sur les chromosomes du cacaoyer. Pour commencer à exploiter cette nouvelle séquence du génome, nous avons conduit une étude QTL à partir d'une descendance entre Trinitario implantée en Guyane, permettant de localiser les régions génomiques impliquées dans la variation de la couleur des fèves de cacao. En s'appuyant sur la version améliorée du génome du Criollo, nous avons identifié deux gènes potentiellement impliqués dans la voie de biosynthèse des anthocyanines et flavo

Moniliophthora Pod Rot (MPR) caused by the fungus Moniliophthora roreri (Cif.) Evans et al., is one of the main limiting factors of cocoa production in Latin America. Currently insufficient information on the biology and epidemiology of the pathogen limits the development of efficient management options to control MPR. This research aims to elucidate MPR development through the following daily microclimatic variables: minimum and maximum temperatures, wetness frequency, average temperature and relative humidity in the highly susceptible cacao clone Pound-7 (incidence = 86% 2008–2013 average). A total of 55 cohorts totaling 2,268 pods of 3–10 cm length, one to two months of age, were tagged weekly. Pods were assessed throughout their lifetime, every one or two weeks, and classified in 3 different categories: healthy, diseased with no sporulation, diseased with sporulating lesions. As a first step, we used Generalized Linear Mixed Models (GLMM) to determine with no a priori the period (when and for how long) each climatic variable was better related with the appearance of symptoms and sporulation. Then the significance of the candidate variables was tested in a complete GLMM. Daily average wetness frequency from day 14 to day 1, before tagging, and daily average maximum temperature from day 4 to day 21, after tagging, were the most explanatory variables of the symptoms appearance. The former was positively linked with the symptoms appearance when the latter exhibited a maximum at 30°C. The most important variables influencing sporulation were daily average minimum temperature from day 35 to day 58 and daily average maximum temperature from day 37 to day 48, both after tagging. Minimum temperature was negatively linked with the sporulation while maximum temperature was positively linked. Results indicated that the fungal microclimatic requirements vary from the early to the late cycle stages, possibly due to the pathogen's long latent period. This information is valuab

Cocoa beans (Theobroma cocoa L.) are the main components for chocolate manufacturing. The beans must be correctly fermented at first. Traditional process to perform the first fermentation (lactic fermentation) often consists in confining cacao beans using banana leaves or a fermentation basket, both of them leading to a poor product thermal insulation and to an inability to mix the product. Box fermenter reduces this loss by using a wood with large thickness (e>3cm), but mixing to homogenize the product is still hard to perform. Automatic fermenters are not rentable for most of producers. Heat (T>45°C) and acidity produced during the fermentation by microbiology activity of yeasts and bacteria are enabling the emergence of potential flavor and taste of future chocolate. In this study, a cylindro-rotative fermenter (FCR-V1) has been built and coconut fibers were used in its structure to confine heat. An axis of rotation (360°) has been integrated to facilitate the turning and homogenization of beans in the fermenter. This axis permits to put fermenter in a vertical position during the anaerobic alcoholic phase of fermentation, and horizontally during acetic phase to take advantage of the mid height filling. For circulation of air flow during turning in acetic phase, two woven rattan with grid have been made, one for the top and second for the bottom of the fermenter. In order to reduce air flow during acetic phase, two airtight covers are put on each grid cover. The efficiency of the turning by this kind of rotation, coupled with homogenization of the temperature, caused by the horizontal position in the acetic phase of the fermenter, contribute to having a good proportion of well-fermented beans (83.23%). In addition, beans'pH values ranged between 4.5 and 5.5. These values are ideal for enzymatic activity in the production of the aromatic compounds inside beans. The regularity of mass loss during all fermentation makes it possible to predict the drying surface corr

Cocoa beans (Theobroma cocoa L.) are the main components for chocolate manufacturing. The beans must be correctly fermented at first. Traditional process to perform the first fermentation (lactic fermentation) often consists in confining cacao beans using banana leaves or a fermentation basket, both of them leading to a poor product thermal insulation and to an inability to mix the product. Box fermenter reduces this loss by using a wood with large thickness (e>3cm), but mixing to homogenize the product is still hard to perform. Automatic fermenters are not rentable for most of producers. Heat (T>45°C) and acidity produced during the fermentation by microbiology activity of yeasts and bacteria are enabling the emergence of potential flavor and taste of future chocolate. In this study, a cylindro-rotative fermenter (FCR-V1) has been built and coconut fibers were used in its structure to confine heat. An axis of rotation (360°) has been integrated to facilitate the turning and homogenization of beans in the fermenter. This axis permits to put fermenter in a vertical position during the anaerobic alcoholic phase of fermentation, and horizontally during acetic phase to take advantage of the mid height filling. For circulation of air flow during turning in acetic phase, two woven rattan with grid have been made, one for the top and second for the bottom of the fermenter. In order to reduce air flow during acetic phase, two airtight covers are put on each grid cover. The efficiency of the turning by this kind of rotation, coupled with homogenization of the temperature, caused by the horizontal position in the acetic phase of the fermenter, contribute to having a good proportion of well-fermented beans (83.23%). In addition, beans'pH values ranged between 4.5 and 5.5. These values are ideal for enzymatic activity in the production of the aromatic compounds inside beans. The regularity of mass loss during all fermentation makes it possible to predict the drying surface corr

Depuis plusieurs années, les programmes de recherche chez le cacaoyer ont mis l'accent sur l'étude des bases génétiques des caractères agronomiques d'intérêt, notamment concernant la résistance aux maladies et la qualité des fèves de cacao, qui représentent deux attributs importants pour la cacaoculture et la production de chocolat. Ce travail présente, par l'exploration du transcriptome et du génome du cacaoyer, la constitution de ressources moléculaires et l'analyse des voies de biosynthèse impliquées dans plusieurs de ces caractères agronomiques d'intérêt. L'étude du transcriptome a permis l'identification de plusieurs dizaines de milliers de gènes exprimés dans divers organes et pour différentes conditions environnementales et ont fourni de nombreux marqueurs moléculaires qui ont été utilisés pour réaliser des cartes génétiques haute densité. Les informations apportées par ce travail ont permis d'engager le séquençage du génome de la variété Criollo du cacaoyer. Son analyse et son annotation ont apporté un ensemble d'informations biologiques cruciales, depuis le catalogue des gènes et éléments mobiles jusqu'aux aspects évolutifs qui a révélé une structure du génome peu remanié par rapport à l'ancêtre commun aux dicotylédones. Par la suite, les travaux que nous avons menés pour améliorer la séquence complète ont conduit à une réduction considérable de la fragmentation chromosomique observée dans la première version. Par ailleurs 97% de la séquence assemblée et 99% des gènes sont désormais ancrés sur les chromosomes du cacaoyer. Pour commencer à exploiter cette nouvelle séquence du génome, nous avons conduit une étude QTL à partir d'une descendance entre Trinitario implantée en Guyane, permettant de localiser les régions génomiques impliquées dans la variation de la couleur des fèves de cacao. En s'appuyant sur la version améliorée du génome du Criollo, nous avons identifié deux gènes potentiellement impliqués dans la voie de biosynthèse des anthocyanines et flavo

Moniliophthora Pod Rot (MPR) caused by the fungus Moniliophthora roreri (Cif.) Evans et al., is one of the main limiting factors of cocoa production in Latin America. Currently insufficient information on the biology and epidemiology of the pathogen limits the development of efficient management options to control MPR. This research aims to elucidate MPR development through the following daily microclimatic variables: minimum and maximum temperatures, wetness frequency, average temperature and relative humidity in the highly susceptible cacao clone Pound-7 (incidence = 86% 2008–2013 average). A total of 55 cohorts totaling 2,268 pods of 3–10 cm length, one to two months of age, were tagged weekly. Pods were assessed throughout their lifetime, every one or two weeks, and classified in 3 different categories: healthy, diseased with no sporulation, diseased with sporulating lesions. As a first step, we used Generalized Linear Mixed Models (GLMM) to determine with no a priori the period (when and for how long) each climatic variable was better related with the appearance of symptoms and sporulation. Then the significance of the candidate variables was tested in a complete GLMM. Daily average wetness frequency from day 14 to day 1, before tagging, and daily average maximum temperature from day 4 to day 21, after tagging, were the most explanatory variables of the symptoms appearance. The former was positively linked with the symptoms appearance when the latter exhibited a maximum at 30°C. The most important variables influencing sporulation were daily average minimum temperature from day 35 to day 58 and daily average maximum temperature from day 37 to day 48, both after tagging. Minimum temperature was negatively linked with the sporulation while maximum temperature was positively linked. Results indicated that the fungal microclimatic requirements vary from the early to the late cycle stages, possibly due to the pathogen's long latent period. This information is valuab

Malgré des caractéristiques organoleptiques très appréciées par les chocolatiers, la grande majorité des productions de cacao malgaches est achetée en " cacao standard " aux petits paysannats. Seules les plantations industrielles mettent en marché du cacao de qualité supérieure. Le cacao de Madagascar figure parmi les rares cacaos fins de la planète. Peu d'études concernant la filière cacaoyère malgache ont été réalisées. Ce travail a pour but de mettre en lumière des liens pouvant exister entre les modes de transformation post-récolte des divers producteurs de fèves de cacao et leur qualité sensorielle. Deux études conduites dans le Sambirano en 2013 dans le cadre du réseau de coopération scientifique en océan Indien QualiREG1 ont permis de faire un point sur les vergers cacaoyers et sur les procédés de transformation dans les différentes zones du Sambirano et les différentes structures de production du petit paysan à la plantation industrielle. Ces études remettent en cause les affirmations communément publiées que le verger cacaoyer est en déclin et que le cacao du Sambirano se dégrade par manque d'encadrement et de compétence des petits producteurs. Elles montrent en effet l'intérêt des familles rurales pour le produit cacao puisque ces dernières sans appui technique ni aide financière cultivent et rénovent à leur rythme les cacaoyères par la mise en oeuvre de dispositifs de plantation et de pratiques culturales comparables à ceux des compagnies industrielles. Les échantillons provenant de divers producteurs de la région du Sambirano (Madagascar) ont été comparés du point de vue biochimique et sensoriel. Les analyses sensorielles et chimiques ont confirmé la qualité des cacaos malgaches et ont montré que les procédés de transformation du cacao mis en oeuvre par les paysans, principalement en sacs, permettent d'obtenir des produits de qualités biochimique et sensorielle équivalentes à celle du procédé suivi par les industriels, lorsque la durée de fermentation es

Malgré des caractéristiques organoleptiques très appréciées par les chocolatiers, la grande majorité des productions de cacao malgaches est achetée en " cacao standard " aux petits paysannats. Seules les plantations industrielles mettent en marché du cacao de qualité supérieure. Le cacao de Madagascar figure parmi les rares cacaos fins de la planète. Peu d'études concernant la filière cacaoyère malgache ont été réalisées. Ce travail a pour but de mettre en lumière des liens pouvant exister entre les modes de transformation post-récolte des divers producteurs de fèves de cacao et leur qualité sensorielle. Deux études conduites dans le Sambirano en 2013 dans le cadre du réseau de coopération scientifique en océan Indien QualiREG1 ont permis de faire un point sur les vergers cacaoyers et sur les procédés de transformation dans les différentes zones du Sambirano et les différentes structures de production du petit paysan à la plantation industrielle. Ces études remettent en cause les affirmations communément publiées que le verger cacaoyer est en déclin et que le cacao du Sambirano se dégrade par manque d'encadrement et de compétence des petits producteurs. Elles montrent en effet l'intérêt des familles rurales pour le produit cacao puisque ces dernières sans appui technique ni aide financière cultivent et rénovent à leur rythme les cacaoyères par la mise en oeuvre de dispositifs de plantation et de pratiques culturales comparables à ceux des compagnies industrielles. Les échantillons provenant de divers producteurs de la région du Sambirano (Madagascar) ont été comparés du point de vue biochimique et sensoriel. Les analyses sensorielles et chimiques ont confirmé la qualité des cacaos malgaches et ont montré que les procédés de transformation du cacao mis en oeuvre par les paysans, principalement en sacs, permettent d'obtenir des produits de qualités biochimique et sensorielle équivalentes à celle du procédé suivi par les industriels, lorsque la durée de fermentation es