Sensory differentiation of Old World wines from New World wines: Has this become more challenging?

The present study aimed to investigate whether, over two recent decades (1997-2018), Old World Wines (OW) and New World Wines (NW) have become more similar or less similar from a sensory perspective. Two 5-year periods were selected within the two-decade period: 1997-2001 (p1) and 2014-2018 (p2). Data comprised descriptors from reviews by seven expert wine critics with descriptors for 31 wines extracted from each review for every year selected. The frequency of citation of descriptors for each of the four wine categories: OW-p1; OW-p2; NW-p1 and NW-p2 was counted. Differences in the citation of descriptors amongst the four categories were calculated by chi-square test. Correspondence analysis (CA) was calculated with the frequency table of descriptors and wine category. In parallel, the level of alcohol was recorded working under the assumption that changing ethanol values might also contribute towards changes in sensory profiles. Significant differences in ethanol content amongst the four categories of wines were calculated with a two-way ANOVA with region (OW or NW) and period (1997-2001; 2014-2018) as fixed factors. The CA demonstrated that time period was a secondary factor after wine region in differentiation of the selected wines by critics. The wines from the latter period showed higher alcohol levels than the wines from the earlier one. The fact that this alcohol increase with time did not result in a convergence in sensory properties amongst wines from the two regions conceivably is due to critics' perception and judgment of wines being affected by historical notions of OW and NW wine differences. Results are discussed in terms of top-down cognitive mechanisms.