Effect of diammonium phosphate supplementation on the amino acid metabolism during fermentation and sensory properties of fresh spine grape (Vitis davidii Foex) wine

Spine grapes (Vitis daviddi Foex) are cultivated in southern China and possess a unique taste and flavor. However, nitrogen-deficiency results in poor quality spine wine. Diammonium phosphate (DAP) was added to spine grape must to determine the effect of DAP supplementation on the evolution of amino acids and associated by-products. DAP addition increased concentrations of amino acids from 73.5 to 101.0mg/L and biogenic amines from 3.9 to 5.0mg/L, but decreased concentrations of higher alcohols from 322.3 to 273.8mg/L and ethyl carbamate from 16.0 to 10.2 mu g/L after fermentation. Sensory evaluation revealed that DAP supplementation kept the unique aroma and taste of fresh spine wine. DAP supplementation can benefit spine grape vinification and improve the quality of fresh spine wine.