‘Chocolat noir’: A new Teinturier red wine grape cultivar with superior enological suitability

Abstract

In Korea, red wine has often been produced from table-grape cultivars such as ‘Campbell Early’ and ‘Muscat Bailey A’. However, their use has limited the production of deeply colored, phenolic-rich red wines. To overcome these constraints, the National Institute of Horticultural and Herbal Science, Rural Development Administration (RDA), developed ‘Chocolat Noir’, a new teinturier wine grape cultivar.

The cultivar is characterized by a teinturier phenotype (pigmented skin and flesh) and a high tannin content. It originated from a cross between ‘Bailey Alicante A’ and ‘Merlot’ in 2011. Among the progenies, line W-11-01-33 was first selected in 2016 for favorable enological traits. For the evaluation of vine growth and fruit characteristics, regional adaptation trials were conducted at eight locations from 2022 to 2025, where the line showed consistently favorable vine performance and fruit characteristics across different growing regions. And the cultivar was finally selected in 2025. An application for plant variety protection was submitted to the Korea Seed & Variety Service (KSVS) in Nov. 2025.

‘Chocolat Noir’ blooms in late May and ripens in early September, approximately 5 d later than ‘Campbell Early’. The average berry weight is 2.4 g. Because both the skin and flesh are intensely pigmented, wines produced under experimental winemaking conditions showed a color intensity of 14.9, approximately 7.5 times that of ‘Campbell Early’ (2.0). Soluble solids reached 21.6 °Bx, indicating that chaptalization may not be required under typical winemaking conditions. Titratable acidity was 5.8 g·L⁻¹ (tartaric acid equivalents), suggesting that acid adjustment may be needed to ensure balanced sensory properties and microbiological stability.

The cultivar is suitable for spur pruning and showed a relatively low incidence of physiological disorders, including berry cracking, even under non-thinned conditions, indicating manageable vineyard performance. High levels of polyphenols and tannins support its potential for varietal use or blending purposes. However, elevated phenolic content may increase astringency and bitterness, requiring careful harvest timing and winemaking management.

Overall, ‘Chocolat Noir’ is well adapted to Korean growing conditions and produces wines with markedly greater color density and high phenolic potential.

(Project No. PJ01668502), Rural Development Administration, Republic of Korea.