For a kosher thanksgiving roasted turkey, is oil a good substitute for butter for brushing the turkey?
I'm not expert on Kosher thing, but what about using chicken schmaltz?
Using olive oil to brush the turkey is a good kosher substitute (due to the prohibition of eating poultry and dairy together). In general, margarine has been used in the past as a butter substitute, but nowadays, most kosher recipes do not use margarine, which has unhealthful fats. They either use canola, olive or coconut oil in baking. For meats and poultry, olive oil is a healthful alternative, although, truthfully, you could also use canola oil.
Oil will work, as will chicken or turkey stock...or even apple cider.