I have seen many countertop materials, including wood....but pine would be the last choice. No matter how much you attempt to seal it, the wide and soft grain will allow moisture in, which will cause the wood to twist and expand and deform. Also, no finish will make the wood harder; so a pine top will mar, dent and scratch quite easily.
Maple, with the grain turned on its tight-grain side, is your best choice....but even this surface will have to be scrubbed and sanitized periodically. Wood does look nice on a countertop, but it requires considerable maintenace. Laminate, solid surface (corian type), granite, soap stone, cement and tile......these are some of the more practical choices.