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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.

Seeds of Parkia biglobosa, also called African locust bean seeds (ALBSs), are used to produce a condiment by subjecting them to cooking, alkaline fermentation, and drying. The objective of this work was to monitor the evolution of the composition of ALBS during spontaneous fermentation. Results showed that the seeds at initial time contained mainly proteins (45%) and lipids (36%). During fermentation, the conversion of this initial composition took place to produce ammonium, free amino acids, and short-chain fatty acids (SCFAs) that accounted for 2%, 10%, and 1.5% dry basis, respectively, which explains the typical flavor of fermented ALBS. This release was also concomitant with biogenic amine production. Along with ammonium and SCFA release, pyrazines were the major volatile organic compounds. Composition modulation was well represented by a Verhulst equation in which the dynamic could be modified by the initial composition of the seed, the pre-cooking step, and the fermentation conditions (temperature and aeration). Practical applications: For nutritional and sustainability reasons, re-integration of vegetable in general and legumes, in particular in our diet, is a current trend. However, only dish that are appealing to consumers are concretely adopted. Fermentation of legumes is interesting in more than one way. It does not involve heat, so thermolabile molecules can be preserved and the financial and energetic costs are low. Biological interesting molecules are produced from the metabolism of microorganisms, and among them, volatile organic compounds that contribute to enhance the flavor of legume dishes. Soumbala is a meal and/or condiment obtained from the fermentation of African locust bean (Parkia biglobosa) seeds (ALBSs), a legume widely spread in west Africa. The final typical sensory properties are known to be due to the alkaline fermentation step by Bacillus species. This paper presents the kinetics of release of various compounds during spontaneous fermentation that may impact the sensory and nutritional properties of the final product. More precisely, the dynamic of the production of free amino acids, free fatty acids, volatile compounds, and biogenic amines are presented and discussed to give insights into the succession of important reactions to control the sensory and nutritional qualities of fermented ALBS (FALBS). This paper shows that further research are necessary to better understand and control the quality of not only FALBS but also similar protein-rich legumes to modulate the quality of the final products.

Citrus juices can be cold-concentrated by crossflow microfiltration (CMF) in order to obtain functional foods enriched in carotenoids, flavonoids and pectins. The work aimed to characterize the organoleptic quality of this type of micronutrient-dense foods through their aroma profile and sensory analysis. Two citrus concentrates with and without a diafiltration step were compared.Both citrus products were very different, linked to aroma compound, sugar and organic acid contents. Due to its sugar/acidity balance and its better aromatic profile responsible for the citrus-floral flavour, the concentrate without diafiltration was preferred by the sensory panel. Thanks to a simple transfer model, we showed that retention of volatiles clearly varied from one aroma compound to another. The terpene hydrocarbons were the most retained by the membrane during CMF, probably because they were strongly associated with insoluble solids by adsorption.Even though the process modified their organoleptic profiles, both citrus-based products were well rated and can be consumed directly as pleasant functional drinks. © 2022 Society of Chemical Industry.

International audience; Bananas are tropical fruits that are perishable and susceptible to fungal diseases, mainly caused by Colletotrichum musae. Antimicrobial emulsion-based coating materials have been used extensively to inhibit the growth of these fungi and extend the shelf life of bananas. Targeted emulsion-based film functionalities offer excellent mechanical, physicochemical and barrier properties and limit fungal growth kinetics. Antifungal compounds, such as essential oils or phenolic compounds, are added to emulsion-based (wax/ biopolymer) coatings to enhance their antimicrobial properties. This study set out to formulate a beeswax-based emulsion for banana coatings using high-pressure homogenisation (HPH) and hydrophilic food-grade/organic coating materials. The particle size distribution, stability and mechanical properties of the film-forming emulsions, water vapour and the oxygen permeabilities of the resulting coating were investigated. The most promising sucrose emulsions were tested as coatings on banana fruits to assess their efficacy against moisture and firmness loss during storage. Adding thymol (0.5% w/w) to the sucrose emulsions further enhanced the inhibition of Colletotrichum musae growth to its barest minimum of

International audience; Severe Acute Malnutrition (SAM) is still a public health issue in many low-income and middle-income countries. Its management has changed with the development of Ready-to-Use Therapeutic Foods (RUTF) that are energy-dense, lipid-based, micronutrient-enriched foods. The purpose of the present study was to define some aspects of the nutritional profile (in particular, lipid content, fatty acids profile, lipophilic vitamin content), oxidative status, and mycotoxin content of three RUTF products (of which two manufactured in Asia and one in Europe), at different time points during their storage. All RUTF displayed good lipid stability, with peroxide values

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 (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.

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.

This research describes on-farm-inoculated cocoa bean fermentation with two selected strains of high aroma-producing Saccharomyces cerevisiae isolated from wine fermentation and their effects on volatile profile of resulted raw cocoa material and sensory characteristics of chocolates produced. Both strains produced suitably flavour-active esters, aldehydes, ketones and pyrazines in raw cocoa. Inoculation of S. cerevisiae at 0.5 g kg−1 significantly improved the volatile profile of raw cocoa beans and enabled production of chocolate with enhanced intense fresh fruits and floral notes. Chocolate produced thereof presented better overall quality attributed whatever the fermentation time in comparison to the chocolate issued from spontaneous fermentation. Our results suggested the ways of using selected enhanced yeasts as S. cerevisiae for on-farm implementation of bean fermentation as promising alternative possibilities to improve the cocoa fermentation process, desirable flavourful raw cocoa material and high-aroma-quality chocolates produced.

Most of volatile flavour compounds occurred during the cocoa postharvest operations including pod storage and fermentation whom effects on these metabolites were aimed by the present study. Three different spontaneous fermentation treatments were performed on the farm, and the main isolated yeasts were identified using PCR-DGGE technique. Fermented cocoa beans were solar-dried, and their flavour compounds were identified using solid phase microextraction technique–gas chromatography–mass spectrometry. The main results showed that Pichia kudriavzevii was common yeast involved in the cocoa fermentation. Thirty flavour precursor compounds grouped into six chemical families including alcohols and pyrazines were identified in raw cocoa samples. ACP showed that short durations of pod storage and fermentation promote the formation of flavour precursors of cocoa. No spontaneous cocoa fermentation treatment influenced the occurrence of aroma compounds. The generation of flavour compounds depends only on the pod storage and the fermentative microorganisms of cocoa.

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

Date palms (Phoenix dactylifera) are an important fruit crop of arid regions of the Middle East and North Africa. Despite its importance, few genomic resources exist for date palms, hampering evolutionary genomic studies of this perennial species. Here we report an improved long-read genome assembly for P. dactylifera that is 772.3 Mb in length, with contig N50 of 897.2 Kb, and use this to perform genome-wide association studies (GWAS) of the sex determining region and 21 fruit traits. We find a fruit color GWAS at the R2R3-MYB transcription factor VIRESCENS gene and identify functional alleles that include a retrotransposon insertion and start codon mutation. We also find a GWAS peak for sugar composition spanning deletion polymorphisms in multiple linked invertase genes. MYB transcription factors and invertase are implicated in fruit color and sugar composition in other crops, demonstrating the importance of parallel evolution in the evolutionary diversification of domesticated species., Nature Communications, 10 (1), ISSN:2041-1723

An innovative process combining roasting and tempering was proposed to promote puffing and mechanical dehulling of jicaro seeds. Roasting was performed at three temperatures (120 °C, 140 °C, and 160 °C) and for six residence times (80–180 s). A previous seed tempering was performed at 15% moisture content for 24 h, by spraying the seeds with an amount of water calculated to reach the final moisture content of 15%. The following parameters were monitored as a function of time to optimize the roasting operation: percentage of open seeds, whiteness of cotyledons, and content of two volatile compounds, 2,5-dimethylpyrazine and ethyl-2-methylbutyrate which are considered as the key jicaro note. The optimal roasting was achieved at 160 °C for 150 s with 90% open seeds. The optimal mechanical dehulling was achieved after tempering the roasted seed at 10% moisture content with a yield of 75%. The lightness evolution followed a zero-order kinetic with an activation energy of 103 kJ mol−1. Ethyl-2-methylbutyrate and 2,5-dimethylpyrazine increased with the temperature and period of roasting. Programa Regional de Seguridad Alimentaria y Nutricional/[C-15-2012]/PRESANCA II/Italia Consejo Superior Universitario Centroamericano/[C-15-2012]/CSUCA/Guatemala Institut Français Amérique Centrale/[]/IFAC/Costa Rica European Union Latin America Academic Links/[]/EULAlinks/Alemania UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)

The transfer kinetics of three labelled compounds (butanal, 2-phenyethanol, isoamyl acetate) was studied from a liquid medium into the coffee beans during simulated wet processing using four media (M) (M1: contained dehulled beans, M2: contained demucilaginated beans, M3: contained depulped beans, M4: contained depulped beans with yeast). Trials were carried out at 25 °C, under agitation and for five time periods (0, 6, 12, 24 and 48 h), and then the labelled volatiles were analyzed by SPME-GC–MS. The three labelled molecules were transferred into the coffee beans with different mass transfer rates; reaching at 12hrs in the M4, 0.2 ± 0.03, 11.2 ± 0.66 and 1.3 ± 0.04 µg/g of coffee respectively for butanal, 2-phenyethanol and isoamyl acetate. The parchment resistance significantly affected the mass transfer of the 2-phenylethanol. Butanal and isoamyl acetate underwent metabolic reactions, which decreased their amount in the coffee beans. Furthermore, an interaction between molecules and the yeast was observed and decreased significantly the butanal’s transfer.

This work describes the formulation of a functional yogurt-like product based on fermented maize with added phytosterols and its oxidative stability during cold storage. The technological challenge was to stabilize 3.5% esterified phytosterols (between 2 and 3 g of free sterols) in a low-fat emulsion and to preserve the obtained product throughout processing and storage. The natural bioactive compounds: lutein, zeaxanthin, β-cryptoxanthin, β-carotene and γ-tocopherol were detected in the yogurt, and remained stable during 12 days of refrigeration. Higher content of C18:1 n-9 and C18:3 n-3 (six and ninefold, respectively) were obtained in samples with phytosterols. This was desirable from a nutritional point of view, but at the same time it induced lipid oxidation that was 1.4-fold higher in the product with phytosterols than in the controls. The use of a multivariate approach served to find descriptors which were related to treatments, and to explain their behavior over time. Fil: Descalzo, Adriana María. Instituto Nacional de Tecnología Agropecuaria; Argentina. Universidad de Morón; Argentina Fil: Rizzo, Sergio Aníbal. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Los Alimentos; Argentina. Universidad de Morón; Argentina Fil: Servent, Adrien. Centre de Coopération Internationale en Recherche Agronomique pour le Développement; Francia. Université de La Reúnion; Francia Fil: Rossetti, Luciana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Los Alimentos; Argentina Fil: Lebrun, Marc. Université de La Reúnion; Francia. Centre de Coopération Internationale en Recherche Agronomique pour le Développement; Francia Fil: Pérez, Carolina Daiana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Los Alimentos; Argentina Fil: Boulanger, Renaud. Université de La Reúnion; Francia. Centre de Coopération Internationale en Recherche Agronomique pour le Développement; Francia Fil: Mestres, Christian. Centre de Coopération Internationale en Recherche Agronomique pour le Développement; Francia. Université de La Reúnion; Francia Fil: Pallet, Dominique. Université de La Reúnion; Francia. Centre de Coopération Internationale en Recherche Agronomique pour le Développement; Francia Fil: Dhuique-Mayer, Claudie. Université de La Reúnion; Francia. Centre de Coopération Internationale en Recherche Agronomique pour le Développement; Francia

The threat of bacterial resistance to antibiotics has created an urgent need to develop new antimicrobials. The aim of this study was to characterize the chemical diversity of Litsea cubeba leaf essential oil (EO) and its impacts on the antibacterial activity against pathogenic bacteria. Essential oils collected from seven provinces in North Vietnam (n=25) were characterized by their high content in either 1,8-cineole or linalool. Linalool-type EOs were more effective against the eight bacterial strains tested than 1,8-cineole-type. Oil samples, LC19 (50% 1,8-cineole) and BV27 (94% linalool), were selected to investigate their antibacterial mechanisms against Escherichia coli. A strong bactericidal effect was observed after 4 and 2h of exposure respectively. Microscopic analysis of treated E.coli cultures clearly showed that EOs caused changes in cell morphology, loss of integrity and permeability of the cell membrane, as well as DNA loss. However, the effects of both EOs were distinct. LC19 mostly affected cell membrane, led to a significant cell filamentation rate and altered cell width, whereas BV27 damaged cell membrane integrity leading to cell permeabilization and altered nucleoid morphology with the appearance of spot and visibly altered compaction. Significance and Impact of the StudyThis study aimed to characterize the chemical diversity of Litsea cubeba leaf essential oil (EO) and its impacts on its antibacterial activity. Two major chemotypes (1,8-cineole or linalool rich) were identified in North Vietnam and both were bactericidal against several pathogenic bacteria. A distinct inhibitory effect of EO samples on Escherichia coli was observed. 1,8-cineole-rich sample (LC19) affected cell membrane, led to cell filamentation and perturbation of cell width, while the linalool-rich one (BV27) induced damages in the cell membrane and changes in the nucleoid morphology. The study demonstrates the importance of considering chemotype variations in terms of chemical composition as well as the mode of action.

International audience; Two fresh (fresh cubic pieces, fresh puree) and two dried (dried cubic pieces, dried powder) products were prepared from a homogenous mango fruit batch to obtain four samples differing in texture. The aromatic profiles were determined by SAFE extraction technique and GC-MS analysis. VOCs released during consumption were trapped by a retronasal aroma-trapping device (RATD) and analysed by GC-MS. Twenty-one terpenes and one ester were identified from the exhaled nose-space. They were amongst the major mango volatile compounds, 10 of which were already reported as being potential key flavour compounds in mango. The in vivo release of aroma compounds was affected by the matrix texture. The intact samples (fresh and dried cubic pieces) released significantly more aroma compounds than disintegrated samples (fresh puree, dried powder). The sensory descriptive analysis findings were in close agreement with the in vivo aroma release data regarding fresh products, in contrast to the dried products.

This paper describes the complete implementation of a blind image algorithm, that takes any digital image as input. In a first step the algorithm estimates a Signal and Frequency Dependent (SFD) noise model. In a second step, the image is denoised by a multiscale adaptation of the Non-local Bayes denoising method. We focus here on a careful analysis of the denoising step and present a detailed discussion of the influence of its parameters. Extensive commented tests of the blind denoising algorithm are presented, on real JPEG images and scans of old photographs.

Jicaro seeds (Crescentia alata) are widely consumed in Central America, primarily as a popular tasty and nutritious beverage called “horchata”. Seeds are roasted to develop a specific aroma through a process that has never been explored. Volatile compounds, extracted from raw and roasted jicaro seeds (140 °C for 140 s) by SAFE (Solvent Assisted Flavor Evaporation), were analyzed by Gas Chromatography/Mass Spectrometry (GC/MS). Twenty-seven volatile compounds were isolated, among which, ethyl-2-methylbutyrate was designated by olfactometry as providing the characteristic jicaro note (0.16 and 0.47 mg/kg dry basis (d.b.) in raw and roasted seeds, respectively). The release of volatile compounds from the Maillard reaction, such as pyrazines, and the increase of ethyl-2-methylbutyrate after roasting, exhausted the pleasant jicaro aroma. This mild roasting process had a slight impact on polyphenol, fructose and free amino acid contents, in agreement with the Maillard reaction. Confocal microscopy showed the coalescence of lipids in roasted jicaro seeds, which might explain the higher extracted fat content. Programa Regional de Seguridad Alimentaria y Nutricional/[C-15-2012]/PRESANCA II/Italia Consejo Superior Universitario Centroamericano/[C-15-2012]/CSUCA/Guatemala Institut Français Amérique Centrale/[]/IFAC/Costa Rica European Union Latin America Academic Links/[EULA1401013]/EULAlinks/Alemania UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)

Biochemical and physical changes of two types of fresh-cut fruits packaged in plastic containers and stocked at 4°C were studied over a period of six days. The first type of container was film-lidded and contained orange juice, pomelo, kiwifruit and orange slices. The second type was plastic-lidded and contained orange juice, apple, kiwifruit and orange slices. Color, vitamin C and carbohydrates changes were investigated. In film-lidded containers, the results showed significant variations of brightness in kiwifruit and pomelo. Carbohydrates decreased in orange juice in plastic-lidded containers. Vitamin C content did not significantly change. These results suggest that carbohydrates oxidation could be prevented by vitamin C and low oxygen observed in containers atmosphere which avoids enzymatic browning in most fruits. Overall, these results indicate a relative good stability of nutrients and well preserved organoleptic qualities of these fresh-cut fruits during the storage. Key words: Fresh-cut fruits, orange juice, carbohydrates, color, vitamin C.

International audience; Food fortification is widely used to address the public health problem of nutrient deficiencies. This study's purpose is to assess the lipid profile and nutritional quality of 13 fortified infant flours (FI) collected “in the field” in Africa and Asia after different periods of storage. The lipid content, fatty acid profiles, lipophilic vitamin content, and lipid oxidation state (peroxide values, secondary oxidation products) are determined. Mycotoxins and packaging materials are also characterized. The lipid content averages 9.1 ± 3.5 g/100 g. Fatty acid profiles are dominated by linoleic (43.3 ± 8.8%), oleic (29.5 ± 7.4%), and palmitic acid (17.8 ± 6.7%) and result in an average ω6/ω3 ratio of 12.2 ± 5.9 but with high values for some FI. Very high overages in vitamins A, D, and E are observed in products stored for short periods (1–6 months), whereas FI stored for more than 12 months has insufficient vitamin content. Lipid oxidation is acceptable but for six products presenting excessive peroxide values. Most products are contaminated by low amounts of mycotoxins but only two FI do not abide by the regulation. A strong correlation between peroxide values, hexanal content, and time of storage is observed. Practical Applications: The expiration dates for FI commercialized in low‐income countries should be shortened from 36 to 12 months so as to guarantee their nutritional quality of these functional foods and to abide by the fortified infant flour legislation. Indeed, FI quality significantly decreases over time of storage. The use of high barrier packaging materials must be generalized, although it is a necessary criterion but not sufficient to ensure the long‐term stability of FI. Special attention should be given to reduce lipophilic vitamin overages and to improve their lipid profile, especially the ω6/ω3 ratio, which has to be lower than 15.

In Senegal, Detarium senegalense J.F. Gmel. (ditax in Wolof) is one of the most important ¶important forest fruit species. ¶However, exploitation of the edible fruit is based on local people’s knowledge. Only trees whose fruits are consumed by animals are exploited. ¶To identify them, a chemical comparison of edible and toxic forms was done in order to highlight differences between both forms. Dichloromethane leaf extracts from toxic and edible trees were analyzed by gas chromatography. Phenolic profile and volatile compounds from fruits extracts were studied respectively by High Performance Liquid Chromatography-mass spectrometry (HPLC-MS) and Gas Chromatography Mass Spectrometry (GC-MS). Cytotoxicity effect of fruits extracts was evaluated on murine macrophage cells J774 A1. GC-analysis of dichloromethane leaf extracts revealed the presence of lupenone and lupeol only in toxic extracts. 6’-O-galloyl-epiheterodendrin and isovaleronitrile were detected in toxic pulp. However, no cytotoxic effect was found in our conditions. This study has given the opportunity to identify within the same species, compounds which could differentiate both edible and toxic forms. Nevertheless further studies are needed to better understand which compounds are responsible for toxicity in the toxic form. Key words: Ditax, Detarium senegalense, toxicity, lupeol, lupenone, cyanogenic glycoside, isovaleronitrile.

Volatile compounds from fresh and dried mango were extracted by the solvent-assisted flavour evaporation (SAFE) technique and analysed by GC-MS. Forty-one and fifty five volatile compounds were identified in fresh and dried mango, respectively. Monoterpenes, followed by sesquiterpenes, lactones and alcohols were the major compounds. Drying induced substantial losses of several compounds. The total amount of volatiles decreased by about 59%. These losses could be mainly attributed to the evaporation of the volatiles during drying, the extent of which seemed to increase with the hydrophobicity and Henry's law constant of the compounds. However, new compounds appeared and enrichment of some compounds was observed after drying. Limonene, β-myrcene, δ-3-carene, β-caryophyllene, γ-butyrolactone and 3-methylbutyl butanoate were found to be flavour contributors in both products on the basis of the odour activity values (OAVs). Mesifuran displayed high OAV only in fresh fruit while hexanal and heptanal only in dried mango. (Resume d'auteur)

Aims: The aims of this study were to characterize the antibacterial activity and the chemotype of Litsea cubeba leaf essential oil (EO) harvested in North Vietnam and to investigate the biological effects induced by the leaf powder on growth, nonspecific immunity and survival of common carp (Cyprinus carpio) challenged with Aeromonas hydrophila. Methods and Results: The EO showed the prevalence of linalool (95%, n = 5). It was bactericidal against the majority of tested strains, with minimum inhibitory concentrations ranging from 0.72 to 2.89 mg ml(-1) (Aer. hydrophila, Edwarsiella tarda, Vibrio furnissii, Vibrio parahaemolyticus, Streptococcus garvieae, Escherichia coli, Salmonella Typhimurium). The fish was fed with 0 (control), 2, 4 and 8% leaf powder supplementation diets for 21 days. Nonspecific immunity parameters (lysozyme, haemolytic and bactericidal activities of plasma) were assessed 21 days after feeding period and before the experimental infection. Weight gain, specific growth rate and feed conversion ratio were improved by supplementation of L. cubeba in a dose-related manner, and a significant difference appeared at the highest dose (8%) when compared to the control. The increase in plasma lysozyme was significant for all the treated groups. Haemolysis activity was higher for the groups fed with 4 and 8% plant powder. Antibacterial activity increased significantly for the 8% dose only. Conclusions: Litsea cubeba leaf powder increased nonspecific immunity of carps in dose-related manner. After infection with Aer. hydrophila, survivals of fish fed with 4 and 8% L. cubeba doses were significantly higher than those fed with 2% dose and the control. Significance and Impact of the Study: A range of 4-8% L. cubeba leaf powder supplementation diet (from specific linalool-rich chemotype) can be used in aquaculture to reduce antibiotic burden and impacts of diseases caused by Aer. hydrophila.

We investigate what arithmetic would look like if carry digits into other digit position were ignored, so that 9 + 4 = 3, 5 + 5 = 0, 9 X 4 = 6, 5 X 4 = 0, and so on. For example, the primes are now 21, 23, 25, 27, 29, 41, 43, 45, 47, ... ., 7 pages. To the memory of Martin Gardner (October 21, 1914 -- May 22, 2010). Revised version (with a number of small improvements), July 7 2011

The volatile compounds of bitter orange (Citrus aurantium L.) products, essential oil (EO) and the heart cut (HC) of the distillate were detected and quantified using gas chromatography (GC) coupled with a mass spectrometer and flame ion- ization detector. The flavour compounds were characterized using GC-olfactometry by nine trained panellists by the fre- quency of detection method. In total, 53 molecules were detected in the EO and 40 in the HC. The EO was characterized by 19 major odour compounds (frequency of detection from 6/9 to 9/9) with different aromatic notes among which a-pinene (floral), octanal (green), limonene (citrus), linalool (floral), a-terpineol (indeterminate: 'ND', green), linalyl acetate (floral), (E,E) or (E,Z)-2,4-decadienal (frying), dodecanal (ND), caryophyllene (green) and an unknown compound (I T =1678, plastic note). The HC presented a complex mixture of several molecules in low concentrations, which characterize the bitter orange flavour. The HC was characterized by seven high FD odour compounds, three of them (myrcene, a-phellandrene, and limonene) with citrus and mint aromatic notes, and the other four ((Z)-linalool oxide, a-terpinolene, linalool and neral) with floral notes. The comparison of these two products brought to light that the overall process of maceration/distillation could induce the loss of 15 strong odours previously found in simple essential oil and characterized by plastic and metal notes. These results show that macerating-distilling bitter orange peels and EO makes it possible to select the most pleasant odour compounds while eliminating some off-odours present in the EO. This is the first time that the characterization of odour-active compounds has been carried out on bitter orange products. This valuable information could help for further investigation on process/product optimization. Copyright © 2011 John Wiley & Sons, Ltd. Several studies detail the composition of the volatile part of bitter orange oil. The percentage content of monoterpene hydrocarbons varies from 97.3% to 97.8%, while sesquiterpene hydrocarbons have a percentage of about 0.2%. Oxygenated compounds have a percentage between 1.8% and 2.2%. Esters are the main oxygenated class. Their content ranges from 0.8% to 1.4%, carbonyl compounds from 0.35% to 0.63% and alcohols from 0.33% to 0.46%. The main component of bitter orange es- sential oil (EO) is limonene, its content being more than 93%. Among the minor monoterpene hydrocarbons, only myrcene al- ways exceeds 1%. Its content ranges from 1.7% to 1.8%, and b- pinene has a percentage of about 1%. Linalyl acetate is the main oxygenated compound and it represents the major part of the esters. Linalool is the main alcohol and octanal and decanal the main carbonyl compounds. (4-13)

Introduction. Les oasis marocaines sont reputees pour le savoir-faire ingenieux de leurs habitants en matiere de gestion et de preservation des ressources naturelles. La datte, principal produit des oasis, beneficie amplement de cette ingeniosite qui connait, de nos jours, une regression et un manque de valorisation. Notre etude a eu pour objectif d'archiver et d'analyser le savoir-faire de la transformation des dattes en jus, localement appele Tassabount, et d'en proposer un mode de valorisation. Materiel et methodes. La methodologie employee pour le travail d'archivage et d'analyse des connaissances locales de transformation des dattes en jus a ete base sur une approche participative impliquant une centaine de femmes oasiennes de la vallee du Drâa (Maroc). Resultats et discussion. Notre etude a mis en evidence une pratique ingenieuse dans la transformation locale des dattes en jus. Ce savoirfaire, developpe par les femmes oasiennes, est etroitement lie a la diversite genetique du palmier dattier (varietes et hybrides). En outre, le Tassabount est identifie comme produit prometteur a valoriser, en misant sur ses qualites organoleptiques et ses vertus therapeutiques. Par ailleurs, la description et l'analyse du procede familial de preparation du Tassabount ont permis d'identifier des voies possibles d'amelioration pour son elaboration et sa stabilisation en vue de son transfert a des entreprises artisanales et/ou industrielles. (Resume d'auteur)

Essential oil samples of Cinnamosma fragrans from two regions in Madagascar, Tsaramandroso (38 samples) and Mariarano (30 samples), were analysed by GC/MS. Fifty-seven components were identified, accounting from 88.3% to 99.4% of the oils' composition. The major components were linalool (72.5 +/- 23.3%) in Tsaramandroso and 1,8-cineole (47.3 +/- 10.2%) in Mariarano. Samples B8 (95.8% linalool) from Tsaramandroso and B143 (71.6% 1,8-cineole) from Mariarano containing the highest proportions of the two main components identified, were selected to determine antimicrobial activities against 10 microbial strains. Bacillus subtilis and Staphylococcus aureus were the most sensitive strains to both oils. Minimum inhibitory concentration (MIC) values were lower for B143 against all tested Gram-negative strains than pure 1,8-cineole. B8 showed higher MIC values than pure linalool against Salmonella typhimurium and Vibrio alginolyticus, and similar MIC values to linalool towards the other Gram-negative strains. Both essential oils exhibited higher MIC values towards Fusarium oxysporum than their respective pure major component. These results suggested the occurrence of synergism or antagonism effects between the different oil constituents. (c) 2008 Elsevier Ltd. All rights reserved.

Introduction. Apres recolte, les fruits du litchi (Litchi chinensis Sonn.) perdent rapidement la couleur rouge lumineuse de leur peau. Le brunissement du litchi recolte a ete en grande partie attribue a la degradation rapide, dans la peau, des colorants rouges d'anthocyanine lies a l'oxydation des composes phenoliques par l'oxydase de polyphenol (PPO) et/ou la peroxydase (POD). Une anthocyanase a ete egalement identifiee dans le pericarpe du litchi. Nos travaux ont cherche a caracteriser deux varietes specifiques de litchi differant considerablement quant a leur couleur et a leur brunissement. Materiel et methodes. Les teneurs en anthocyanes, oxydase (PPO) de polyphenol, peroxydase (POD) et anthocyanase du pericarpe de deux cultivars de litchi, Kwai May et Wai Chee, developpes respectivement a l'ile de la Reunion et en Espagne ont ete etudiees. Resultats et discussion. La composition qualitative des anthocyanines preponderantes (3-rutinoside de cyanidol et 3-glucoside de cyanidol) a ete identique pour les deux cultivars etudies, mais, quantitativement, la variete Kwai May a eu une concentration en 3-rutinoside de cyanidol inferieure a celle Wai Chee (64% en moins). Pour les deux cultivars, ce composant a represente plus de 90% des anthocyanines totales. L'activite de la PPO a ete 6 fois plus grande pour la variete Kwai May que pour Way Chee et l'activite de la POD a ete 30 fois plus grande. L'activite de la POD a ete plus grande que celle de la PPO pour les deux varietes. Ces differences aident a expliquer les differents comportements des cultivars pendant les etudes apres recoltes. (Resume d'auteur)

Introduction. Les aromes sont souvent utilises comme marqueur de la qualite du fruit. Pour la caracterisation des dattes (Phoenix dactylifera), plusieurs chercheurs ont utilise l'analyse des composes volatils. Neanmoins, il est difficile d'analyser cet arome tenu malgre les nombreuses techniques disponibles, comme les extractions liquide-liquide et l'analyse d'espace de tete. L'utilisation du nez electronique, qui necessite une manipulation minimale de l'echantillon, est une autre technique; elle est rapide et efficace. Cet outil assez nouveau, qui simule le comportement du nez humain, a donc eveille notre interet pour une application aux dattes. Materiel et methodes. Les dattes de neuf varietes de dattier ont ete recoltees, en 2005, au stade Tamar, a Zagora, Maroc. Elles ont ete congelees apres recolte et envoyees par avion au laboratoire du CIRAD (Montpellier, France). Toutes les donnees ont ete collectees en meme temps. Cinq cents g de dattes ont ete preleves au hasard parmi la recolte. Celles-ci ont ete denoyautees et decoupees en petits morceaux. Apres homogeneisation, une partie aliquote de 3.0 g a ete mise dans un flacon d'espace de tete de 10 mL et immediatement scellee. Six repetitions par echantillon ont ete preparees pour les analyses au nez electronique ulterieures. Un nez electronique (Alpha MOS) equipe de capteurs a base d'oxydes metalliques a ete utilise. Les donnees ont ete traitees par une analyse en composantes principales (ACP). L'index de discrimination (DI), cree par Alpha MOS, a ete utilise pour decrire le pouvoir discriminatoire de la separation des groupes. Alpha MOS considere que de bonnes discrimination et fiabilite sont obtenues pour des DI superieures a 80%. Resultats. Des index de discrimination superieurs a 88% et les moyennes des coefficients de variation obtenus pour chaque capteur inferieures a 4% montrent le haut niveau de performance et la bonne reproductibilite du nez electronique. Conclusion. Le nez electronique est sensible aux emissions volatiles de dattes. Toutes les varietes de datte etudiees ont ete bien separees. Cette technique rapide de criblage, qui cree une empreinte olfactive specifique comme veritable carte d'identite, pourrait etre utilisee pour suivre des changements de maturite, verifier l'identite d'un bon nombre de dattes et detecter des adulterations. (Resume d'auteur)

The camera calibration parameters and the image processing chain which generated a given image are generally not available to the receiver. This happens for example with scanned photographs and for most JPEG images. These images have undergone various nonlinear contrast changes and also linear and nonlinear filters. To deal with remnant noise in such images, we introduce a general nonparametric intensity and frequency-dependent noise model. We demonstrate by simulated and experiments with real images that this model, which requires the estimation of more than 1000 parameters, performs an efficient noise estimation. The proposed noise model is a patch model. Its estimation can therefore be used as a preliminary step to any patch-based denoising method. Our noise estimation method introduces several new tools for performing this complex estimation. One of them is a new sparse patch distance function permitting to find noisy patches with similar underlying geometry. A validation of the noise model and of its estimation method is obtained by comparing its results to ground-truth noise curves for both raw and JPEG-encoded images, and by visual inspection of the denoising results of real images. A fair comparison with the state of the art is also performed.

Arguably several thousands papers are dedicated to image denoising. Most papers assume a fixed noise model, mainly white Gaussian or Poissonian. This assumption is only valid for raw images. Yet, in most images handled by the public and even by scientists, the noise model is imperfectly known or unknown. End users only dispose the result of a complex image processing chain effectuated by uncontrolled hardware and software (and sometimes by chemical means). For such images, recent progress in noise estimation permits to estimate from a single image a noise model, which is simultaneously signal and frequency dependent. We propose here a multiscale denoising algorithm adapted to this broad noise model. This leads to a blind denoising algorithm which we demonstrate on real JPEG images and on scans of old photographs for which the formation model is unknown. The consistency of this algorithm is also verified on simulated distorted images. This algorithm is finally compared with the unique state of the art previous blind denoising method.

Introduction. Chez Ananas comosus, les variations entre clones des caracteristiques organoleptiques sont faibles; celles entre varietes sont plus marquees. Une dizaine d'hybrides Cayenne × Perolera a ete selectionnee par le Cirad pour etre developpee commercialement. Ils presentent des profils aromatiques distincts des parents. L'ananas doit etre recolte relativement vert pour pouvoir parvenir en bon etat sur les marches consommateurs. L'arome degage pouvant inciter le consommateur a acheter le fruit frais, nous avons etudie, sur differentes varietes et hybrides, l'impact du stade de maturation du fruit a la recolte et de la duree de conservation sur l'emission des composes volatils. Materiel et methodes. Les differences de teneurs en composes volatils entre les varietes d'ananas ont pu etre mesurees par extraction en espace de tete par SPME (fibre PDMS 100 µm), suivie d'une analyse CPG/FID sur colonne Stabilwax. Les analyses ont porte sur les fruits de quatre ou cinq clones de chacune des varietes Cayenne, Perolera, Queen, Rondon, ainsi que de cinq hybrides Cirad et d'un hybride MD2. L'impact du stade de maturite (extrait sec et acidite libre) et des conditions de conservation sur les composes volatils a ete evalue. Resultats et discussion. Les profils aromatiques obtenus pour les clones d'une meme variete ont ete tres semblables et les differences intervarietales se sont revelees repetables. Au cours de la maturation, une augmentation de l'emission des composes volatils s'est produite avant la pleine maturation. La conservation au froid entre 13°C et 24°C a provoque une forte augmentation de l'emission aromatique. Conclusion. Differencier les profils aromatiques par SPME/GC-FID de differentes varietes d'ananas semble possible malgre leur grande similitude. Une identification plus poussee, par GC-MS, des composes volatils d'ananas de differentes origines pourrait permettre de mieux preciser leur caracterisation. (Resume d'auteur)

Pasteurized pineapple juice was concentrated by osmotic evaporation to produce a 51 °Brix concentrate that was reconstituted to single strength juice for evaluation. Headspace gas chromatography (HSGC) showed that the concentrate retained an average of 62% of the volatile components present in the initial juice. A sensory panel preferred initial juice over reconstituted concentrate, and noted a decrease in desirable flavor top notes as well as development of some processed flavor in the concentrate. Similar HSGC analysis of four other commercial juice samples showed a wide range of quantitative values for volatile components, with the initial juice being similar to the weakest of these commercial juices. Analysis of concentrated juice extracts permitted identification of additional less-volatile components not monitored directly by HSGC of the juice. Relatively low levels of these components were also present in the initial juice. Although this nonthermally produced concentrate retains more volatile components than when traditional thermal processing methods are used, addition of aqueous aroma to the concentrate may be required for satisfactory flavor. L'interet pour des methodes non thermiques de concentration de jus de fruit augmente depuis quelques annees. Dans cette etude, du jus d'ananas pasteurise est concentre par evaporation osmotique et le concentrat est reconstitue en un jus homogene pour l'evaluation de sa qualite. Des methodes analytiques sont utilisees pour determiner les teneurs en composes volatils pendant le procede de concentration et les profils de ces composes sont compares avec ceux de jus commerciaux prepares par concentration thermique.