The recipes for cooking white asparagus (the kind popular in Germany, not the green one) add a few things to the water for cooking that seem a bit odd to me. Typical recipes use some or all of the following ingredients
- salt
- sugar
- lemon juice
- butter
Salt I understand of course. The lemon juice is supposed to affect the color or prevent discoloration, which seems plausible enough. I'm not sure about the sugar, the asparagus didn't really taste bitter or so without it. But the ingredient that makes me wonder the most is the butter.
Adding butter to the cooking water here seems similar to the often discredited advice to put olive oil in the water for cooking pasta. Oil and water don't really mix, so adding butter seems unlikely to affect the flavor of the asparagus a lot. So it seems like this would be a waster of butter for no or minimal effect. And it seems even more pointless as you typically add a far superior butter delivery device like Sauce Hollondaise to white asparagus.
Are there good reasons to add these ingredients, especially the butter?