Influence of harvest maturity on quality of cold stored Vitis vinifera L. cv. ‘Thompson Seedless’ and ‘Red Globe’ table grapes, with special reference to berry split

Abstract

Effect of harvest maturity on quality of Thompson Seedless' and ‘Red Globe’ table grapes after cold storage at −0.5°C and a subsequent shelf life was investigated. Berry split decreased significantly for grapes harvested at more advanced maturities. By harvesting ‘Thompson Seedless’ grapes at total soluble solids (TSS) 20 °Brix and titratable acids (TA) 0.4%, instead of TSS 17.3 °Brix and lower, and TA 0.5% and higher, the incidence of post-storage berry split was reduced by ca. 87%. By harvesting ‘Red Globe’ grapes at TSS 16.1 °Brix, instead of TSS 15.0 °Brix and lower, berry split was reduced by ca. 78%. However, grapes harvested too mature showed an increase in stem desiccation and SO₂ damage around the pedicel end of berries for both cultivars. ‘Thompson Seedless’ grapes harvested too mature also showed an increase in Botrytis decay. To ensure acceptable quality of cold stored Thompson Seedless' and ‘Red Globe’ table grapes, it is imperative to harvest as soon as possible after horticultural maturity has been reached.

Keywords:

• Botrytis decay
• SO₂ damage
• stem desiccation