Quality Attributes of Four Table Grape Varieties at Harvest and During Storage and Shelf Life

Abstract

After harvest, table grape berries undergo physical and chemical changes even with optimal storage conditions, and postharvest fruit quality retention varies among varieties. This study evaluated four varieties over a two-year period: Lasta, Lyana, recently released seedless variety Nada, and the widely cultivated Muscat Hamburg. At harvest, variety x year interaction affected yield, berry weight, and berry size, while differences among varieties were observed for rachis weight (p < 0.001) and the number of berries per cluster. During storage and shelf life, analyzed separately by experimental year, no berries with mechanical disorders or decay incidence were observed. Weight loss increased during storage in all the varieties, and this was particularly pronounced during the shelf-life period. Berry firmness ranged from 5.7 to 27.8 N/mm2 depending on variety and storage duration. After 28 days of cold storage, increased berry firmness compared with harvest was recorded only in variety Nada. In 2024, Nada exhibited the highest total soluble solids content at harvest and, after 28 days of cold storage, reached 28.2%, significantly exceeding its harvest value and the SSC of the other varieties at the same evaluation time. Varieties showed different potential for cold storage. After 28 days in cold storage, sensory acceptance scores for Lasta and Nada decreased significantly compared to harvest, mainly due to increased rachis browning and berry skin shriveling. Muscat Hamburg showed the lowest rachis browning during storage. This study demonstrates the importance of selecting table grape varieties adapted to diverse environmental conditions and capable of maintaining postharvest quality during cold storage and shelf life.