3 tablespoons flour mixed with 3 tablespoons cold water Place roast in slow cooker/Crock Pot; sprinkle with salt and pepper. Combine juice concentrate, brown sugar, nutmeg, and allspice; pour over roast. Cover and cook on high for 1 hour. Reduce heat to low and cook for 8 hours. Before serving, skim juices and pour cooking liquid into a small saucepan. Whisk in the flour-water mixture. Bring to a boil, stirring, and continue cooking until thickened. Serve gravy with the pork roast.