Salt concentration and salty taste perception in Chardonnay and Shiraz wines from own roots and different rootstocks under saline irrigation

Abstract

Salty taste can adversely affect the marketability of wine. To further examine salty taste, basic compositional and sensory assessment was conducted on ‘Chardonnay’ and ‘Shiraz’ wines produced from vines irrigated with salty water with a mean electrical conductivity of 1.5 dS m-1. Vines of the cultivars on own roots and on up to five rootstocks that differed in capacity for chloride and sodium exclusion were used. The sensory attributes salty and viscosity were enhanced for the ‘Chardonnay’ wine from K51-40 rootstock with elevated chloride and sodium concentrations of 407.4 and 374.2 mg L-1, respectively, and a potassium concentration of 470.1 mg L-1, but not affected in ‘Shiraz’ wine from K51-40 with concentrations of 274.1, 130.5 and 1,110 mg L-1, respectively. The salty and viscosity attributes in the ‘Chardonnay’ wine from K51-40 were closely associated and approximately equally correlated with the concentration of chloride and sodium, with the wine also having lower acidity and a higher overall fruit aroma. The chloride concentration in wine that aligns with perception of salty taste by a trained panel may be similar between a white and red wine. Wine chloride concentration above approximately 400 mg L-1 appears linked with, and a potential indicator of, salty taste, however the specific contribution of sodium and potassium requires further study.