Something I've noticed about German culture in general, which bleeds into food culture, is punctuality: Germans really value people being on time and do not appreciate when someone is even a few minutes late. When you're eating with Germans, showing up even a few minutes late can be considered disrespectful.
Compared to the more laid-back American culture around time, and the even more laid-back Ghanaian culture where tardiness enters the realm of hours, not just minutes, this is a major cultural difference.
Another thing I've noticed is that Germans are very upfront about whether they like or dislike someone's food. Growing up in a culture where you're told to finish the meal and be respectful, even if you didn't enjoy the dish, at first this was a shock to me. After some time, I've learned to accept the straightforwardness for what it is rather than see it as a sign of disrespect. But it is still sometimes surprising.
The last major tradition/cultural difference I've noticed actually has a legal basis. The official drinking age in Germany is 16, as opposed to 21 in the United States. This means that it is much more common to see youth participating in drinking beer or wine at the dinner table.
