Influence of the sociocultural perspective on the sensory perception of wine consumers in Mexico and Spain.

The increasing globalization of companies and markets, including the wine market, makes this study important as a cultural comparison between the sensory perception of wine in Mexico and Spain. Eighty consumers were selected with different consumption habits, and hedonic (Acceptance and Simple Preference) and descriptive (Word Association Task and the Check-All-That-Apply (CATA) method) sensory tests were performed. The results revealed that there were differences in the conceptualization of wine in the Word Association Task. Both populations preferred wines of Spanish origin over those of Mexican origin, especially in the case of red wine. Finally, the results of the CATA method showed that the attributes that discriminate the two types of wine are due more to the country origin of the tasters than to the samples. Spanish consumers used cultural and tradition descriptors and were stricter when it came to sensory evaluation. Moreover, Spanish participants demonstrated more ability to differentiating all wines in terms of visual, olfactory and taste aspects.

Effect of the Metal-Ligand Interface on the Chiroptical Activity of Cysteine-Protected Nanoparticles.

Gold, silver, and copper small nanoparticles (NPs), with average size ≈2 nm, are synthesized and afterward protected with l- and d-cysteine, demonstrating emergence of chiroptical activity in the wavelength range of 250-400 nm for all three metals with respect to the bare nanoparticles and ligands alone. Silver-cysteine (Ag-Cys) NPs display the higher anisotropy factor, whereas gold-cysteine (Au-Cys) NPs show optical and chiroptical signatures slightly more displaced to the visible range. A larger number of circular dichroism (CD) bands with smaller intensity, as compared to gold and silver, is observed for the first time for copper-cysteine (Cu-Cys) NPs. The manifestation of optical and chiroptical responses upon cysteine adsorption and the differences between the spectra corresponding to each metal are mainly dictated by the metal-ligand interface, as supported by a comparison with calculations of the oscillatory and rotatory strengths based on time-dependent density functional theory, using a metal-ligand interface motif model, which closely resembles the experimental absorption and CD spectra. These results are useful to demonstrate the relevance of the interface between chiral ligands and the metal surfaces of Au, Ag, and Cu NPs, and provide evidence and further insights into the origin of the transfer mechanisms and induction of extrinsic chirality.