Bread-Bakers v105.n015.13

I see Fiori di Sicilia in many Panettone recipes.  King Arthur carries 
it.  But I was surprised to see on their web site the ingredients were 
listed as "citrus and vanilla".  Is that all it is?  I thought it was from 
a flower.  Is there any reason not to substitute half vanilla half citrus 
extracts?