Daniel, you need to up your arsenal for stain removal. Citrus Gel is a brilliant product but is best suited to oily type residues such as Oil, Grease, Blue Tac, Chewing Gum, Tar etc.
For food spillages such as this an Enzyme based product would be best. Something like Enzall sprayed on and left to dwell for 15 minutes would remove the bulk. Sometimes you are left with colourant from the product. This is where you need to either use a Reducer or Oxidiser. These either add or take away Oxygen from the stain making it invisible. An example of a reducer would be a Coffee stain remover and an Oxidiser is something like Dyegone.