Selection of indigenous strains with good oenological and aroma characteristics for winemaking in Ningxia China.

Ningxia is one of the well-known wine producing regions in China. However, the oenological and aroma characteristics of indigenous yeasts remains hidden. The fermentative and oenological properties including stress resistance, hydrogen sulfide, foam production levels; killer phenotype, and flocculation of 89 Ningxia indigenous isolates and ten commercial yeasts were evaluated. The fermentative and oenological properties of the tested strains varied significantly. They could resist 500 g/L glucose, 300 mg/L SO, 14% (/v) ethanol and pH 2.8, and produce more esters. They also produce low levels of ethanol and could conduct fermentations vigorously and at a high rate. Cabernet Sauvignon wines made with NXU 21-24 showed the high intensity of tropical fruit, dry fruit, temperate fruit, and spicy flavor. The floral flavor in NXU 21-102 fermented wine is very intense. The indigenous strains of NXU 21-102 and NXU 21-24 exhibited potential use as starter cultures in wine production.