The aim of this study was to evaluate the effect of the food matrix on polyphenol bioaccessibility and antioxidant activity during the in-vitro digestion of dairy and egg products enriched with grape extracts (GE). Four GE-enriched matrices produced under industrial conditions (custard dessert, milkshake, pancake and omelet) and the GE dissolved in water (control solution) were submitted to in vitro digestion and the bioaccessibility of the major classes of polyphenols as well as the evolution of the antioxidant activity of the matrices were monitored at oral, gastric and intestinal level. Apart from the digestion effect itself, the release, stability and solubility of polyphenols was governed by mainly two factors: 1-the composition and structure of the food matrices and 2-the class of polyphenol. Results showed that the inclusion of the GE extracts into the different egg and dairy food matrices greatly impacted the release and solubility of anthocyanins and proanthocyanidins during digestion, especially in the solid food matrices and during the oral and gastric phases of digestion. Also, the presence of the food matrices protected anthocyanin from degradation during the intestinal phase. However, if the total phenolic content is considered at the end of the whole digestion process, the proportion of soluble (bioaccessible) and insoluble phenolics delivered by the enriched-matrices was quite similar to that of the control solution. On the contrary, the food matrix effect did not affect the antioxidant activity of the matrices, which remained constant during the oral and gastric phases but greatly increased during the intestinal phase of digestion. Among the GEenriched matrices, omelet presented higher recoveries of total phenolics and antioxidant activity at the end of digestion.

Industrial processing of raspberries into juice and jam results in the production of with high content of lipophilic and hydrophilic phytochemicals. Usually considered as waste, raspberry pomace is occasionally cold‐pressed to recover specialty oil. However, the resulting pomace press‐cake (PPC) still contains 30% to 35% of lipophilic compounds, such as essential fatty acids, tocols, phytosterols, and ellagitannins initially present in pomace. In a perspective of sustainable development, we investigate an eco‐friendly process using an aqueous enzyme‐assisted extraction (AEAE) to simultaneously and effectively recover lipophilic compounds and polyphenols from the PPC. The performance of different combinations of carbohydrases and proteases was compared. After selecting the best enzymatic system, a definitive screening design involving six factors was then implemented to optimize the process. Under optimized conditions, 1.2 units of thermostable alkaline protease/100 g PPC, pH 9, 60 °C, and 2 hr hydrolysis, more than 38% of total PPC lipophilic content were recovered in the aqueous medium. The recovery of polyphenols and antioxidant activity was, respectively, 48% and 25% higher than obtained by extraction with methanol/acetone/water mixture. Such an AEAE extract might prove useful in food and nutraceutical applications. Practical Application Raspberry pomace, a food industrial by‐product, is often considered as waste. However, it is a rich source of phytochemicals, such as tocols, polyphenols, and polyunsaturated fatty acids. To overcome the drawbacks of organic solvent use, an enzyme‐assisted extraction process was developed as an eco‐friendly alternative to recover these bioactive compounds. Definitive screening design experimental design was used to enhance polyphenols and lipophilics extraction yields while reducing process costs. This extract is an oil‐in‐water emulsion, with high content in antioxidant phytochemicals, which might have potential for use in nutraceutical applications. Therefore, this green process developed for the valorization of raspberry pomace is considered as a perspective of sustainable development.

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The color of rosé wines is extremely diverse and a key element in their marketing. It is due to the presence of anthocyanins and of additional pigments derived from them and from other wine constituents. To explore the pigment composition and determine its links with color, 268 commercial rosé wines were analysed. The concentration of 125 polyphenolic compounds was determined by a targeted metabolomics approach using ultra high-performance liquid chromatography coupled to triple quadrupole mass spectrometry (UHPLC-QqQ-MS) analysis in the Multiple Reaction Monitoring (MRM) mode and the color characterised by spectrophotometry and CieLab parameters. Chemometrics analysis of the composition and color data showed that although color intensity is primarily determined by polyphenol extraction (especially anthocyanins and flavanols) from the grapes, different color styles correspond to different pigment compositions. The salmon shade of light rosé wines is mostly due to pyranoanthocyanin pigments, resulting from reactions of anthocyanins with phenolic acids and pyruvic acid, a yeast metabolite. Redness of intermediate color wines is related to anthocyanins and carboxypoyranoanthocyanins and that of dark rosé wines to products of anthocyanin reactions with flavanols while yellowness of these wines is associated to oxidation.