How did my Turkish Delights/lokum end up tasting like orange?
I strongly suspect that your food coloring may have had something to do with it if you were using liquid food coloring as these often have flavors you wouldn't expect. That plus the acidity from the coffee (yes, coffee is acidic) and the cream of tartar (powdered acid) could simulate an orange flavor. 

Gel colorings are much better as they give much more color without flavors, I'd suggest those in the future, just remember a very little bit goes a long way.