Wooden bowls, cutting boards and tools should always be washed quickly by hand, never allowed to soak, and never placed in a dishwasher. Kitchen supply stores sell expensive mineral oil for your wood items. There is no need. Go to your local pharmacy and get mineral oil in the laxative section. It will save you money and save your wood. The reason food grade mineral oil is used is that it does not turn rancid. I oil my cutting boards after each washing and bowls when needed. Oiling keep the wood from absorbing liquids that can spoil and turn the wood funny colors. Oil also keeps the wood from cracking and splitting.