Answer: When liver is grilled, the blood contained inside it is removed, as we have discussed in the previous Halacha. It is therefore permissible to cook liver in water or fry it in oil after it has been grilled and this is not problematic whatsoever. According to the Rama, however, which is indeed the prevalent Ashkenazi custom, one should act stringently and wash off the liver after grilling it and before cooking it. Nevertheless, even if one has not washed off the liver after grilling it and immediately cooks it, the liver is still permitted for consumption.
What Kind of Liver May be Cooked or Fried
The only kind of liver which may be cooked after having been grilled is only one which was grilled within three days of the animal’s slaughter. However, if three days or more have elapsed from the time of the animal’s slaughter, the liver may only be eaten after being grilled and it may not be subjected to any other method of cooking after it has been grilled, for after three days have passed, its blood congeals within it and it does not exit completely by means of grilling. Thus, when the liver is cooked after having been grilled, the blood still congealed within it is released into the food and it turns out that this dish has blood mixed into it. Nevertheless, it is permissible to eat the liver after having been grilled alone, for although there is some congealed blood remaining in the liver, this blood is not forbidden for consumption while it is still absorbed inside the liver and only becomes forbidden when it is released from the liver (by means of cooking and the like).
One must be aware that many livers sold in stores today have already had three days elapse from the animal’s slaughter and may only be eaten grilled but may not be cooked after having been grilled. Only if the date of the animal’s slaughter is clearly indicated may one cook the liver after having grilled it if this is being done within three days of the date and time of slaughter.
There are several fine and reliable Kashrut supervisions which have begun printing on the labels attached to the liver when the animal was slaughtered and until what date and time one may cook or fry the liver after having been grilled. In this way one may cook or fry the liver without any concern.
Frozen Liver
Maran Rabbeinu Ovadia Yosef zt”l writes that liver which was placed into a deep freeze within three days of the animal’s slaughter does not have the same law as liver which three days have elapsed; even if this liver stays frozen for an extended amount of time, it may be cooked after having been grilled as long as three days have not yet elapsed since its thawing.
