As a rule of thumb, the darker the wine, greater tannins it has. When grape juice is fermented to make wine, yeast converts the sugar from the grapes into alcohol and carbon dioxide. This often changes after awhile and sometimes closed or light wines on the nose will open up as they age. https://vibrant-mango-kvlmct.mystrikingly.com/blog/removing-a-crumbled-cork-from-your-wine-bottle