One of my favorite summertime meals is a grilled brat with sauerkraut. The word sauerkraut means "sour cabbage" in German. It's processed by natural fermentation, one of the oldest methods of food preservation.
Debbie Botzek-Linn is a retired extension food safety educator at the University of Minnesota. She says it's important to use the right variety of cabbage.
"When you're making sauerkraut, you want to be sure to start with firm, sweet, mature heads of cabbage, particularly mid-to-late-season crops. What that means is there's early cabbage, and later cabbage. I'd like to recommend later cabbage," says Botzek-Linn. "That variety makes a better quality sauerkraut."
The only other ingredient you need is canning or pickling salt. Don't use table salt because the iodine in it will prevent the necessary bacterial fermentation. Botzek-Linn says it's very important that you measure the salt correctly for the fermentation process to work as it should.
Save the outside leaves of the cabbage head and put them aside to use for sealing the product. Shred the rest, mix it with the salt, and put it into an earthenware crock or a food-grade plastic container. Pack it just tight enough to get the air out.
"There's a couple different ways that you can seal the sauerkraut product," she says. "The one I like to use is again washing the leaves and putting the leaves over the top of the packed shredded cabbage, and then I have a plate that I put over that, and I put a jug of water on top of that and cover it with a dish towel. You also can use a food-grade plastic bag, fill it with water, and put that on top and that does a really nice job too."
The amount of time it takes to turn cabbage into sauerkraut depends on the room temperature. Allow three-to-four-weeks at 68-to-74-degrees.