First: If you're imagining a full-sized American fridge, stop right there. Most apartments come only with a mini refrigerator, like the one you probably had in college. My current refrigerator isn't tall enough to ride a roller coaster.
Is it because kitchens are smaller? Is it the fact that Germans don't refrigerate a lot of things that Americans do? Who knows why, but it means that the few items that earn a permanent place in the fridge are chosen all the more carefully.
Here are five things nearly every German has in her (tiny) fridge.
1. Käse und Wurst: Cheese and Sausage
Really and truly at number one, cheese and sausage do triple duty on any given day. You might pull out the sliced meat and cheese for breakfast, sandwiches for lunch, or a light dinner.
2. Senf: Mustard
Not only does every German fridge have mustard of some sort, but it's also not uncommon to have several different types of mustard. After all, different sausage calls for different mustard.
Brand loyalty matters, too. A vegetarian friend who grew up in East Germany confessed that she keeps a tub of Bautz'ner mustard in her refrigerator at all times because her mother would kill her if she visited and it wasn't there.
3. Butter: Butter
It is hard to overstate the heights to which Germans take their love of butter. Bread and butter is a legitimate open-faced sandwich option. Expect to find high-fat European-style butter, the spreadable kind in a tub, or a homemade compound butter with plenty of fresh herbs. Suddenly the bread and butter sandwich sounds pretty good, actually.
4. Gurken: Pickles
It's probably more accurate to say Schraubglas mit undefinierbarem Inhalt, or a glass jar with unidentifiable content. It's safe to assume that the content is often gherkins or some kind of pickled vegetable, although we had a glass jar of homemade elderflower cordial tucked at the back of our fridge for the better part of a year before we gave up and threw it out. Something pickled or preserved is basically inevitable in this pickle- and preserve-heavy lifestyle.
5. Flaschenbier und Mineralwasser: Beer and Sparkling Water
Visit your German friends and you'll likely be offered some cold bottled beer from the fridge or some sparkling water. Despite the fact that tap water is very good across Germany, almost every household will stock several bottles of mineral water. I'd go for the beer, myself; hopefully your host has stocked up on a beer from their hometown in Bavaria!
A caveat: Keep in mind, though, that while certain cultural stereotypes are true, Germany is a big and increasingly diverse country of over 80 million people. For every sausage in a German fridge, there is a jar of kimchi next to the mustard or Belgian endive in the crisper. For the most part, though, bet on the Wurst.