Certainly not all fruitcakes contain alcohol, but this recipe was based on one I made with my mother as a child and the alcohol of choice was sherry. Since sherry is a fortified wine, high in sugar, and has not been lab tested, I was not going to use it in our low FODMAP version.   You can use brandy or whiskey for this recipe, or you could make and use our Low FODMAP Orange Liqueur. Either would be lovely.