"An old and good method for carrying food over time is preserving by lactic fermentation. This method is still used for making sauerkraut, but can be used for a multitude of other vegetables.

From the book, Keeping Food Fresh, Old World Techniques and Recipes (ISBN 1-890132-10-1):
The vegetables are grated or cut up, seasoned with a bit of salt (or a mild brine) and herbs, and left to soak in their own juice. (Salt is a key: A good rule of thumb is about 1 1/2 percent salt by weight of vegetables, which generally translates into 2 to 3 tablespoons of salt per quart.) Lactic microbial organism - similar to those that curdle milk - develop spontaneously and convert the natural sugars of the vegetable into lactic acid. This environment rapidly acidifies, to the point that it becomes impossible for bacteria responsible for food spoilage to multiply. Vegetables preserved this way will keep in a cool place, such as a cellar, for many months.

I highly recommend the above mentioned book for time-tested techniques on food preservation. In addition to the chapter on preserving by lactic fermentation, other chapters address preserving by drying, with salt, with sugar, in oil, in vinegar, and in alcohol. Really a valuable little book."