Grapefruit zest in lieu of lemon zest?

[queueueuq]

I was about to make some shortbread raspberry tarts when I discovered I'm out of lemons! The filling calls for lemon zest. I do have grapefruit on hand -- would grapefruit zest be an acceptable substitute or would it be too bitter, perhaps? I'm guessing it's safe but just thought I'd check in case there's something I'm overlooking.

[queueueuq]

Well, I'm happy to report that the grapefruit zest was not a disaster -- it actually made little difference. I did notice the absence of lemon zest, but not so much the presence of grapefruit zest. There's a good amount of lemon juice in the filling (I had juice in the freezer but not zest) so that may have helped. Or perhaps I "lucked" out with a flavourless fruit.

Good tip about the medications, greygarious!

[greygarious]

One thing to keep in mind when using grapefruit in anything that will be eaten by people with whose medical conditions you are not familiar is that it has an adverse interaction with a number of prescription medications including some for heart problems. Not to be messed with. This is not a problem with other forms of citrus, though I wouldn't take a chance on pommelo, either.

[queueueuq]

Well, I should've been more patient. I went ahead with it before reading your warnings. Hopefully, it'll turn out ok -- will report back!

[magiesmom]

I like tartness against sweet and I think it would be really good, though different.

[chefj]

The zest does not really add any acid (tartness) at all.

[chowser]

I'd leave it out, too. Add more vanilla extract, or if you want a different flavor, maybe a tiny bit of almond extract.

[queueueuq]

Mmm, I may try with almond extract some other time!

[chefj]

Sure, but you would have Grapefruit flavored instead of Lemon.

[todao]

I wouldn't try substituting lemon zest with grapefruit. The flavors are distinctly different and, while I don't know of any danger using grapefruit zest, I simply wouldn't recommend it for the use you describe. It works well with some seafood dishes though so keep it in mind for a shrimp or scallop recipe.