Discovering Vitis Vinifera (L.) Biodiversity: Berry Quality Traits of Four Unexploited Table Grape Genotypes

The conservation and characterization of grapevine (Vitis vinifera L.) germplasm are essential for supporting breeding programs and discovering new genotypes suitable for fresh consumption or as a source of health benefit molecules. In this study, four unexploited white-skinned, seeded table grape genotypes (Emilia, ID III/32, ID VI/6, ID VIII/5) from the Dalmasso Crosses (ID) collection were characterized for their berry quality traits. Morphological measurements and secondary metabolite analyses, including total polyphenols (TP), total flavonoids (TF), total proanthocyanidins (PA), flavonol (Fl) profile, and volatile organic compounds (VOCs) were conducted to evaluate their potential for fresh consumption and breeding. The berry antioxidant capacity (AC) was evaluated by using three assays: ABTS, DPPH and FRAP. Emilia and ID VI/6 showed larger berry size (from 24 to 25 mm as berry width). ID VIII/5 displayed the highest TP in skin and PA content in both skin and seed, along with the highest AC. ID III/32 and ID VIII/5 exhibited a strong muscat-like aroma due to high levels of monoterpenes, particularly linalool (48.6 and 62.0%, respectively) and geraniol (33.5 and 22.5%, respectively). The study highlights the potential of these genotypes for fresh consumption and as valuable sources of phenolic compounds and aroma traits for table grape breeding programs.