'Taste' in the Bible

Then all the people came to give David food. Still on that day, David swore, "{May God punish me} if I taste food or anything before the sun goes down."

I [am] eighty years old today. Can I discern between good and bad? Or can your servant taste what I eat or what I drink? Or can I still hear the voice of singing men and women? Why should your servant be a burden any longer to my lord the king?