Effect of different SO₂ addition on the quality of 'Beibinghong' dry red wine

In order to investigate the effects of different SO₂ addition on the quality of 'Beibinghong' dry red wine, using 'Beibinghong' picked in 2019 as the test material, dry red wine was brewed by adding SO₂ with different mass concentrations. The contents of residual sugar, total acid, organic acid, anthocyanin content, color and sensory evaluation of dry red wine samples were determined, and the quality was evaluated comprehensively by principal component analysis (PCA). The results showed that the 'Beibinghong' dry red wine brewed with 50 mg/kg SO₂ addition had the lowest residual sugar content (4.74 g/L), and the highest anthocyanoside content (279.43 mg/L) and better color with 40 mg/kg SO₂ addition. The content of total acid (5.45 g/L), total organic acid (5.44 g/L), malic acid (0.15 g/L) and citric acid (0.18 g/L) in 'Beibinghong' dry red wine brewed with 30 mg/kg SO₂ addition was the lowest, and the content of lactic acid (0.89 g/L) and succinic acid (0.61 g/L) was the highest, which could effectively reduce the acidity of 'Beibinghong' dry red wine. The wine was mellow, moderate acidity, soft taste, and the sensory score (96.01) was the highest. Combined with PCA, the overall quality of 'Beibinghong' dry red wine was the optimal when the SO₂ addition was 30 mg/kg.