Uva di Troja

Main Characteristics of the Uva di Troja Grape

The Uva di Troja grape variety has gained widespread distribution and recognition due to the development of commercial winemaking in Apulia. The variety demonstrates high productivity and the ability to yield a deeply colored, dense must, which ensured its priority when establishing new vineyards in the Barletta district, as well as in the provinces of Bari and Capitanata. Harvest characteristics depend heavily on the altitude above sea level: on coastal plains, the variety ensures the production of dense wine materials in demand for blending, whereas on higher elevations, even with an identical soil composition, the must becomes less dense and less intensive in color. The ripening period belongs to the medium-late category and occurs in the third decade of September. The Uva di Troja variety stands out for its high sugar accumulation potential, reaching 26.07% with a low titratable acidity level of the berry juice at 4.7 g/l.

Morphological Description of the Uva di Troja Grape Variety

Morphological features of the vegetative and generative organs of the variety:

• Mature annual shoot (cane): Has a longitudinally furrowed smooth surface, characterized by moderate thickness and a firm structure. The bark is colored reddish. Internodes are short. Nodes have no thickenings and do not differ in color from the main shoot. Buds are protruding, covered with flake-like down.
• Young shoot (tip): Characterized by intensive flake-like pubescence of a milky-white color with red dots. The first unfolding leaves have an intensive dark red (vinous) coloration. Tendrils are bifurcated, thin, reddish, and form in large numbers.
• Formed leaf: Medium or small in size, with a dense consistency, moderately rough and wrinkled surface with slight waviness. The upper side of the leaf is glabrous, colored light green, acquiring a darker shade in autumn. The lower side is covered with dense flake-like pubescence of a greenish-white color. The blade is five-lobed with regular lobes that are elongated at the ends. The lateral sinuses are shallow, narrow, rounded, and open. The petiolar sinus is completely closed due to the overlapping of the margins of the lower lobes. The leaf margin has small, sharp, shallow teeth without curves. Veins are weakly prominent, with distinct reddening in the central part. The petiole is medium in length, thin, and colored vinous-red. Leaf fall occurs late.
• Cluster: Has a distinctly long cylindrical shape with lobes (wings), characterized by medium density (semi-loose structure). The overall cluster mass is medium. The rachis is firm, without a specific color. The cluster peduncle is powerful and elongated. The berry pedicels are long and dark green in color.
• Berry: Has a medium size and regular spherical shape. The skin is firm, tough, and leathery, with a glossy shine and weak waxy bloom, colored dark blue. The pulp is semi-liquid, and the taste is sweet, balanced, with weak astringency and a light varietal aroma. Inside the berry, small elongated seeds of a vinous color with yellow dots are contained. The berries are firmly attached to the pedicels and possess absolute resistance to bunch rot.

Agrotechnical Features of the Uva di Troja Variety

The Uva di Troja grape variety possesses moderate growth vigor, forming a loose canopy. The vines demonstrate high resistance to spring radiation frosts. The grape prefers well-warmed, sunny sites with clay-calcareous soils. The traditional form of vine training is low-trained bush-like cultivation (alberello) without the use of artificial supports, in which exclusively short pruning to spurs is applied. Spring budburst and flowering occur early, and flower fertilization passes easily, ensuring a stable and abundant yield over the years without a tendency to millerandage of the berries.

Winemaking and Product Characteristics

The Uva di Troja grape variety is the main raw material for the production of wines known in trade under the name "wine from Barletta". In its pure form, the varietal must ensures the production of dense, intensively colored wine materials with an alcohol content of up to 13% ABV; however, the finished wine retains a characteristic roughness ("ruvidezza") that does not disappear even with long aging. To soften the taste and increase the lightness of the wine, producers traditionally practice co-processing Uva di Troja grapes with the Somarello variety. When transported to the northern regions of Italy, due to the more loose structure of the clusters and the increase in berry size, the grape loses its technical properties and is predominantly used as a table grape for fresh consumption.