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The quality of chocolate products proven by consumer acceptability mostly depends on cocoa volatile compounds. In fact, aroma profile of cocoa or chocolate is correlated to cocoa genotype, culture conditions, postharvest practices, and chocolate manufacturing. To the best of our knowledge, no study has been published on both sugars and aromas of controlled cocoa hybrids from Cameroon. The present study aimed at analyzing biochemical and volatile composition of six hand-pollinated cocoa hybrids belonging to different traditional groups. Specifically, the sugar profile was obtained by high performance ion chromatography-electrochemical detector (HPIC-ED) and aroma composition was analyzed using headspace solid phase micro-extraction coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS) on fermented dried beans and roasted nibs. The content of sugars was variable among hybrids and fructose showed the highest concentration in all hybrids in the two matrices. Roasting decreased sugar content. However, the decrease in sugar content seemed genotype dependent. A total of 48 volatile aromas were classified in six groups according to their odor description (fruity, floral, chocolate/nutty, buttery/creamy, undesirable, and unknown). Fruity flavors were not specific to a given chemical group. However, floral volatiles were specific to terpenes, chocolate/nutty to pyrazines, buttery/creamy to lactones and undesirable to phenols and acids. Principal component analysis (PCA) showed specificity of each hybrid and the hierarchical cluster analysis (HCA) Heatmap presented four distinct groups. SCA12 × ICS40 with the highest pyrazine concentration was associated with important content of sugars. Roasting of nibs reduced total volatiles and particularly fruity volatiles whereas other flavor groups moderately increased. In fact, some volatiles such as 2,3-butanediol, 2-nonanol, linalool, β-myrcene, cis/trans-β-ocimene, 2-nonanone, 2-heptanol, methyl acetate, acetophenone could be used as markers in separating traditional cocoa groups in Cameroon.

Cocoa (Theobroma cacao L.) is the only tree that can produce cocoa. Cocoa beans are highly sought after by chocolate makers to produce chocolate. Cocoa can be fine aromatic, characterized by floral and fruity notes, or it can be described as standard cocoa with a more pronounced cocoa aroma and bitterness. In this study, the genetic and biochemical determinants of sensorial notes and nonvolatile compounds related to bitterness, astringency, fat content, and protein content will be investigated in two populations: a cultivated modern Nacional population and a population of cocoa accessions collected recently in the Ecuadorian South Amazonia area of origin of the Nacional ancestral variety. For this purpose, a genome-wide association study (GWAS) was carried out on both populations, with results of biochemical compounds evaluated by near-infrared spectroscopy (NIRS) assays and with sensory evaluations. Twenty areas of associations were detected for sensorial data especially bitterness and astringency. Fifty-three areas of associations were detected linked to nonvolatile compounds. A total of 81 candidate genes could be identified in the areas of the association.

International audience; The present study aims at developing an analytical methodology which allows correlating sensory poles of chocolate to their chemical characteristics and, eventually, to those of the cocoa beans used for its preparation. Trained panelists investigated several samples of chocolate, and they divided them into four sensorial poles (characterized by 36 different descriptors) attributable to chocolate flavor. The same samples were analyzed by six different techniques: Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS), Solid Phase Micro Extraction-Gas Chromatography-Mass Spectroscopy (SPME-GC-MS), High-Performance Liquid Chromatography (HPLC) (for the quantification of eight organic acids), Ultra High Performance Liquid Chromatography coupled to triple-quadrupole Mass Spectrometry (UHPLC-QqQ-MS) for polyphenol quantification, 3D front face fluorescence Spectroscopy and Near Infrared Spectroscopy (NIRS). A multi-block classification approach (Sequential and Orthogonalized-Partial Least Squares – SO-PLS) has been used, in order to exploit the chemical information to predict the sensorial poles of samples. Among thirty-one test samples, only two were misclassified.

International audience; "Mapuey" tubers in Venezuela are staple food for indigenous peoples from the Caribbean coast and Amazon regions. Noticeable differences between genotypes of yam starches were observed. Granules were large, triangular, or shell-shaped with monomodal particle size distribution between 24.5 and 35.5 mu m. Differential scanning calorimetry (DSC) analyses revealed onset gelatinization temperatures from 69.1 to 73.4 degrees C with high gelatinization enthalpy changes from 22.4 to 25.3 J g(-1). All X-ray diffractograms of starches exhibit B-type crystallinity. Crystallinity degrees varied from 24% to 40%. The highest crystallinity was found for the genotype having the highest amylose content. lodo-colorimetric, amperometric, and DSC amylose determinations varied from 1.4 to 8.7%, 2.2 to 5.9%, and 1.4 to 3.5% for Amazonian genotypes, in comparison with commercial Mapuey starches: 12.0, 9.5, and 8.7%, respectively. Solubility and swelling power at 90 degrees C varied from 2.1 to 4.4% and 20.5 to 37.0%, respectively. Gel clarity fluctuated from 22.4 to 79.2%, and high rapid visco analyzer (RVA) viscosity was developed at 5% starch suspension (between 1430 and 2250 cP). Amylopectin weight average molar mass (M) over bar (w), radius of gyration (R) over bar (G), hydrodynamic coefficient nu(G), and apparent molecular density d(Gapp) were determined using high-performance size exclusion chromatography (HPSEC) and asymmetrical flow field flow fractionation (A4F) techniques coupled with multiangle laser light scattering (MALLS) on the Dioscorea trifida genotypes exhibiting the lowest and highest amylose contents. Amylopectins showed very similar molecular conformations. (M) over bar (w) values were 1.15 x 10(8) and 9.06 x 10(7) g mol(-1) using HPSEC and A4F, respectively, thus, 3-5 times lower than those reported with the same techniques for other yam species, and very close to those of potato and cassava amylopectins. This discovery of a new natural amylose-free starch in the neglected yam "Mapuey" could present some potential for the food industry.