The gastronomic symbol of the région is undoubtedly the Choucroute, a local variety of Sauerkraut. The word Sauerkraut in Alsatian has the form sûrkrût, same as in other southwestern German dialects, and means "sour cabbage" as its Standard German equivalent. This word was included into the French language as choucroute. To make it, the cabbage is finely shredded, layered with salt and juniper and left to ferment in wooden barrels. Sauerkraut can be served with poultry, pork, sausage or even fish. Traditionally it is served with Strasbourg sausage or frankfurters, bacon, smoked pork or smoked Morteau or Montbéliard sausages, or a selection of other pork products. Served alongside are often roasted or steamed potatoes or dumplings.

Answer this question, if possible (if impossible, reply "unanswerable"): Pork products are left to ferment in what?
unanswerable