No filter, just as it is, everyday life in Portugal. After a drive several hours off the beaten track, we arrived at a charming B&B in the valley of the Duoro. The lady of the house spared no efforts to arrange us a delicious super. She went to her neighbour to ask him for some lettuce. She came back with 2 lettuces, this one was for the next day. I was amazed by the original way to keep this lettuce fresh.