Study On The Variation Of Free SO₂ And Electrochemical Parameters During Aging Of Large Can Wine

In this experiment,Cabernet Sauvignon dry red wine in a stainless steel tank（100 T,10 m high,3.6 m diameter）of Xin Puwang Winery in Shanshan County,Turpan,Xinjiang was used as the material to explore the variation of free SO₂ content and electrochemical parameters in the tank.The main research contents and results are as follows:1.Changes of free SO₂ content in large-scale wine storage tanks during 2015 and 2019 were studied by one-year monitoring.The results showed that the free SO₂ content increased from the top to the bottom of the tank,and the added SO₂ content decreased rapidly in the new wine.The free SO₂ content consumption at the top of the tank was faster than other parts in the tank,the Wine sample 2019（A）speed could reach8.97 mg/L during the two SO₂ additions.2.Through the one-year electrochemical parameter tracking test of large wine storage tanks in different vintages,the results showed that the dissolved oxygen,（DO）value and the oxidation-reduction potential（ORP）value were decreased with the decrease of liquid level depth in the tank.The DO content decreased with the time passed by,while the ORP value increased slowly.The DO value of the new wine was significantly higher than the wine aged for several years（P<0.01）.The initial value of 1 m from the liquid level was 3.11 mg/L,and decreased by 0.84 mg/L after 4 months.3.The effects of different concentrations of free SO₂ and dissolved oxygen on the color,anthocyanin content,color and hue of Cabernet Sauvignon dry red wine were observed by simulating aging,in order to obtain the appropriate amount of SO₂ .The results showed that keeping 2 mg/（L·month）DO in wine could promote the moderate polymerization of anthocyanins and tannins in wine and improve the quality of wine.Keeping free SO₂ at 25 mg/L is suitable for the aging of Cabernet Sauvignon dry red wine.4.The kinetic model of DO consumption was established.By studying the changes of SO₂ content,DO content and wine composition in the oxidation process,the PLS model of SO₂ and DO consumption was established.The model can well explain the dynamic changes of SO₂ ,DO and wine composition in the oxidation process of wine.5.In the process of accelerated oxidation of Cabernet Sauvignon dry red wine,the relationship between free SO₂ and ORP was studied.The results showed that on the seventh day of accelerated oxidation,the free SO₂ of all treatments decreased to less than 5.22 mg/L,and the ORP increased rapidly to about 350m V in the early stage,and slowed down in the later stage.The change was closely related to the content of free SO₂ in wine.The analysis of ORP and free SO₂ changes in wines with different initial free SO₂ contents during accelerated oxidation showed that there was a significant negative correlation between free SO₂ content and ORP.In this paper,the variation law of free and electrochemical parameters in large cans of Cabernet Sauvignon dry red wine during aging was studied.Under the premise of ensuring that the total sulfur was not exceeded and the quality of wine was not affected,the amount of sulfur dioxide in wine was reduced as much as possible.It lays a theoretical foundation for innovating the way of adding sulfur dioxide and improving wine quality.In the wine food safety and wine industry as a whole has important practical significance.