what is a good liquid to replace tequila with? I'm looking to try a marinade recipe I found recently that calls for tequila. However one of my friends is unable to consume alcohol. What would be a good flavorful liquid to use? I'm looking for a flavor that is fairly similar or at least somewhat close.

Here's the recipe I'm looking to make courtesy of Alton Brown

Ingredients


3 cloves garlic 
1 cup packed cilantro leaves
2 limes, zested
2 teaspoons ground cumin
1 1/2 teaspoons kosher salt
1 teaspoon freshly ground black pepper
1/4 cup tequila
1 pound tilapia fillets
1 tablespoon olive oil


Directions

Put the garlic, cilantro, lime zest, cumin, salt, and pepper in a small food processor bowl and pulse until combined, approximately 20 seconds. With the processor running, add the tequila. Put the tilapia fillets into a 1 gallon resealable bag, add the garlic mixture and move around to coat each fillet. Set aside at room temperature for 15 to 20 minutes.

Heat an electric nonstick griddle to 375 degrees F.

Brush the griddle with the olive oil. Cook the fillets until just cooked through and opaque about 3 to 4 minutes per side. Cut into strips and serve in warm tortillas with crema, shredded red cabbage and lime wedges.
The tequila probably plays two roles in the recipe: as flavor and as a solvent.  The alcohol in the tequila will dissolve certain components in spices that water or oil do not. On the flavor side, tequila is basically a floral smell, so (and sniff together before you say no) why not try rose essence and honey with maybe a tiny bit of some cinnamon.  You can find cooking rose water in ethnic food stores.  It is used in Persian and Indian cooking.