Reisling Wine Sediment

[Kcwhippet]

Welcome to the Wine Board, Srug. The sediment may of more than a single origin. It may be that the winery bottles their wines unfiltered and this could be the leftover by-product of fermentation left in to add some additional character and flavor. However, I don't know many wineries that do this with Riesling. The more likely answer is that it's potassium bitartrate crystals which form when the wine has been chilled below a certain point. Many wineries cold filter their white wines to remove the tartrates, but some don't. The crystals are harmless, and you may know them in their other guise as cream of tartar. Many wineries sell the tartrates they remove from their wines to companies that clean the tartrates further, grind them to a powder and sell them to you in the Baking section of the supermarket. BTW, what's the winery you got the wine from?