Berge might find it convenient to make a small batch of light roux and keep it in a jar in the refrigerator. Then its easy to thicken liquids to just-right consistency with small applications of roux. Be sure to always use a clean spoon to remove the roux from the jar. That way it will keep for several weeks in the refrigerator. Roux doesn't freeze well as the water molecules separate from the starch.
An alternative is to thicken the strained meat juices with a slurry of corn starch, potato flour, or arrowroot using wine, cold stock, or water. Add slowly over heat and keep whisking as they thicken at a lower temperature than a roux. Corn starch would be my last choice as i don't like the shine it gives a sauce.