From trmm hdsn prjcts
Defrutum was a syrup made in ancient Rome by boiling down wine, with the addition of spices and occasionally dried fruit such as figs or quinces. Defrutum would have had a thick, honey-like consistency and served to sweeten and color sauces as well to preserve foods. Defrutum can be made with fresh grapes.
Sources
Sources for the information above include:
A translation of Apicius with an excellent introduction and essays by Christopher Grocock and Sally Grainger
Recipes
{{#dpl: | category=*Recipes | linksto=Defrutum | ordermethod=category,sortkey | headingmode=H4 }}