Slice mushroom caps in half, then slice the caps into quarters to create bite-size mushroom pieces. In a 4-quart soup pot over medium-high heat, sauté the leek, carrot, and celery in vegetable oil for 6 minutes. Stir in garlic and mushrooms and sauté for another 6 to 8 minutes, or until mushrooms have reduced in size and released most of their liquid.Pour in the wine and simmer for 2 minutes, then stir in parsnip, vegetable broth, bay leaves, allspice, caraway seeds (if using), marjoram, sauerkraut, sauerkraut juice, and ground black pepper. Increase heat and bring to a gentle boil, then reduce heat, stir occasionally and cover.