The effects of vintage and cane girdling on the texture properties of some table grape cultivars in a cool climate region

Texture profil analysis of five Hungarian-bred grape cultivars (‘Éva’, ‘Kozma Pálné’, ‘Favorit’, ‘Muscat Pölöskei’ and ‘Pannónia’) was carried out between 2020 and 2022 in the northern part of Hungary. The objectives of the study were to investigate the effect of vintage and the application of girdling as a special canopy management method. ‘Favorit’ and ‘Muscat Pölöskei’ were girdled at the berry development stage of pea-size and at veraison in 2022. Berry mechanical properties (berry hardness – BH, skin hardness – F_sk, skin thickness – Sp_sk) are evaluated by TA.XTplus Texture Analyzer at the same maturity status (°Brix ≥16) for each cultivar. The total soluble solids (°Brix), as well as the berry size, were measured. Based on the average temperature and precipitation data during the intensive berry development phase (April-August), 2020 and 2022 were drier years, and 2022 was the driest and hottest year compared to 2020 and 2021. Results show that ‘Éva’, ‘Favorit’, ‘Pannónia’, and ‘Muscat Pölöskei’ had softer berries and ‘Favorit’ and ‘Pannonia’ had softer skin in 2020 and 2022 compared to 2021. In 2021, the amount and distribution of percipitation were more favorable than in other years throughout the berry growth period. Regarding the texture analysis, girdling at both time resulted in harder berries compared to the control for ‘Favorit’ and ‘Muscat Pölöskei’ in 2022. F_sk showed significantly higher values for pea-size girdling compared to the control and the veraison girdled samples of ‘Pölöskei muskotaly’. Early (pea-size) girdled berry samples had greater diameters and weights for both cultivars than samples from the other two treatments. In conclusion, vintage greatly influences berry texture properties. Indeed, a drier year results in softer skin and softer berries. Howewer, girdling may reduce the so called vinteage impact and result in benefical effects on mechanical properties.