Sunday dinners at Grandpa's house are special occasions. To reduce the burden of feeding fourteen people on my poor grandmother, my mother and aunts would prepare their part of the meal at home and bring it over in huge steaming pots. Such was the case when I attempted to make vegetable soup.
I arrived early with this appetizer and Grandpa met me at the door. He suggested we put my soup on the stove to keep it warm. Together we tasted the broth and both realized immediately that it was too salty! I was embarrassed and worried that I had let everyone down, again. I couldn't even make soup right! In my haste to get over to my Grandfather's house I had gone and added too much salt and now the soup was ruined.
"Hold on,"' Grandpa says, "I know a thing or two about salty soup".
I can't imagine how anyone could take the salt out of soup, I lamented. When was I going to learn? Never doubt Grandpa!
Grandpa peeled a potato and chopped it in half. Then he dropped both halves into the soup and brought the mixture to a boil on the stove. We waited for about five minutes before he took the potato halves out of the soup. To my surprise, the soup wasn't salty anymore - the potato was.
Grandpa told me then that the starch on the exposed flesh of the potato absorbed the salt in the soup.