Screening of ordinary commercial varieties of apple fruits under different storage conditions for their potential vascular and metabolic protective properties.

Epidemiological studies reported that apple consumption is associated with a decrease of cardiovascular and metabolic dysfunction, probably due to the polyphenols and fibers present in this fruit. The storage conditions and genetic origin of apples have been reported to influence their content and, as a consequence, their pharmacological properties. The present study evaluated the influence of varieties and storage conditions of traditional and highly appreciated apples including Gala, Golden Delicious, Granny Smith and Pink Lady varieties after harvest and storage under classic cold conditions, under a controlled atmosphere, or under extreme ultra-low oxygen conditions. Thus, a multi-parametric screening on cell models associated with vascular and metabolic dysfunctions - such as endothelial and smooth muscle cells, hepatocytes, adipocytes and macrophages - in relation to the apple polyphenol content has been developed. This strategy demonstrated that, overall, peeled apple samples exhibited a vascular tropism and acted mainly on proliferation and oxidative stress in endothelial and smooth muscle cells. Apple extracts appeared to be less effective on adipocytes and macrophages, but they exhibited antioxidant properties in hepatocytes. Among the varieties, Gala and Golden Delicious were the most efficient against the processes involved in the development of atherosclerosis. Concerning storage conditions, most of the apple varieties were more efficient under harvest conditions, while they could not be discriminated under all other cold conditions and the concentration used, except for the Gala samples. Interestingly, pharmacological properties were associated with the polyphenol profiles of freeze dried apple flesh powder. The present report revealed the potential use of some apple extracts as effective food supplements or nutraceuticals for the prevention and/or management of cardiovascular and metabolic diseases.

Sensory representation of typicality of Cabernet franc wines related to phenolic composition: impact of ripening stage and maceration time.

Phenolics are responsible for important sensory properties of red wines, including colour, astringency, and possibly bitterness. From a technical viewpoint, the harvest date and the maceration duration are critical decisions for producing red wine with a distinctive style. But little is known about the evolution of phenolics and of their extractability during ripening to predict the composition of the wine and related sensory properties. The aim of this study was to understand the relationship between the sensory profile of the wines and (i) the ripening stage of the berries (harvest date) and (ii) the extraction time (maceration duration). Phenolic acids, flavonols, anthocyanins and proanthocyanidins of Vitis Vinifera var. Cabernet franc were measured in grapes and in wines from two stages of maturity and with two maceration durations. Phenolic composition was analysed by high performance liquid chromatography, after fractionation and thiolysis for proanthocyanidins. The distinctive style of wines was investigated by descriptive analysis (trained panel), Just About Right profiles and typicality assessment (wine expert panel). Relationships between phenolics and sensory attributes were established by multidimensional analysis, and phenolics were classified according to sensory data by ANOVA and PLS regressions. Astringency, bitterness, colour intensity and alcohol significantly increased with ripening and astringency and colour intensity increased with maceration time. Grape anthocyanins increased and thiolysis yield significantly decreased with ripening. In wine, proanthocyanidins increased, and mean degree of polymerisation and thiolysis yield decreased with longer extraction time. The high impact of harvest date on the sensory profiles could be due to changes in anthocyanin and sugar contents, but also to an evolution of proanthocyanidins. Moreover, proanthocyanidin composition was affected by maceration time as suggested by the decrease of thiolysis yield. Our results suggest that the wine sensory quality established by the expert panel, is linked as expected to grape quality at harvest, reflected by sugar and anthocyanin contents, but also by thiolysis yield, which requires elucidation.

Evolution of the localisation and composition of phenolics in grape skin between veraison and maturity in relation to water availability and some climatic conditions.

BACKGROUND: Several studies have investigated the composition of phenolics in grape skin during grape maturation under various conditions of light exposure, water stress, nitrogen supply and mineral nutrition, but their localisation during berry development is not well known. In this study the composition and localisation of proanthocyanidins were monitored for three years on four plots known to induce a distinctive behaviour of the vine (Cabernet Franc). The composition of phenolics was determined by spectrophotometry; also, in one year, proanthocyanidins were determined by high-performance liquid chromatography. Further information was obtained histochemically by means of toluidine blue O staining and image analysis. RESULTS: The results indicated that clear differences in phenolic quantification existed between the biochemical and histochemical approaches; the proportion of cells without phenolics was not linked with the quantity determined by the analytical methods used. The histochemical method showed the evolution of the localisation and typology of cells with and without phenolics during ripening. The number of cells without any phenolic compounds appeared to be very dependent on the mesoclimatic conditions and only slightly dependent on the site water status. CONCLUSION: Clear differences in phenolic quantification existed between the biochemical and histochemical approaches; the proportion of cells with phenolics was not linked with the quantity determined by biochemistry. The histochemical method showed an evolution of the localisation and typology of cells with and without phenolics in which mesoclimatic conditions were the most influential factor. Finally, the study showed some advantages of the histochemical approach: it gives information about the anatomy of the tissue as well as the nature and distribution of some of the large macromolecules and allows reconstruction of the three-dimensional plant structure.

Sensory dimension of wine typicality related to a terroir by Quantitative Descriptive Analysis, Just About Right analysis and typicality assessment.

The distinctive French wine style "Anjou Village Brissac" was investigated through Quantitative Descriptive Analysis by a sensory expert panel, through Just About Right analysis by wine experts, and through assessment of the typicality by wine experts. Typicality was defined as perceived representativeness, with good examples of the concept being considered more typical. Wine experts were producers, winemakers, and enologists from the area. Three types of data were used: (i) quantitative descriptive data on a non-structured scale, (ii) preference data that corresponded to a global typicality index for the wine on a non-structured scale, (iii) data collected on a Just About Right non-structured scale, where the middle of the scale, for each attribute, corresponded to Just About Right, an ideal of typicality for wine experts. The two panels, sensorial experts and wine experts, rated 24 Cabernet franc wines from different French "Appellation d'Origine Contrôlée", including two-thirds "Anjou Village Brissac". Single factor analysis was performed on each panel's data, and results were compared. Multifactor analysis was performed with the data of both panels to highlight the correspondence between the panels. ANOVAs conducted on the differences to the ideal scores permitted the wines to be sorted according to the similarity of their profiles. A penalty analysis was performed to determine, for each attribute, if the rankings on the Just About Right scale were related to significantly different results in the preference scores. Therefore, multivariate analysis of Just About Right scales served (i) to show an ideal point, (ii) to point out the distance between each product, (iii) and to evaluate the consensus of producers. The results showed the relevance of the sensory expert panels in discriminating the products. The panel of wine experts proved relevant for characterizing the global quality of the wines but did not appear consensual for some attributes. Some attributes from the wine expert panel could be explained by precise descriptors generated by the sensory expert panel. Typicality ratings were considered in relation with descriptive ratings, for example astringency and color attributes. The results presented in this study suggest the usefulness of these sensory techniques for describing wine typicality related to a terroir.

Anatomical, histological, and histochemical changes in grape seeds from Vitis vinifera L. cv Cabernet franc during fruit development.

Cabernet franc berries were sampled at five stages from berry set to harvest from an experimental vineyard in mid Loire Valley. Seeds were collected from representative berries in term of stage of development. The evolution of seed was followed both macro- and microscopically. For microscopy analysis, seeds were cut, put in a fixation solution, and cut into thin sections with a microtome. Five staining solutions were used for each seed sample: toluidine blue O, phloroglucinol, periodic acid-Schiff's reagent and naphtol blue black, vanillin, and p-dimethylaminocinnamaldehyde. Toluidine blue O staining revealed the evolution of tissue structures during grape seed development. We studied the changes in chemical compounds (lignin, polysaccharides, proteins, and tannins) with the other reagents. Seed lignification was achieved at veraison. Proanthocyanidins were localized in epidermis, inner cells of the soft seed coat, and inner cell layer of the inner integument. Finally, the localization of flavan-3-ols was linked with changes in cell walls of the outer integument.