Disinfect the lettuce in a container with water and antibacterial for 20 minutes.
Wash the fruit with water and pat dry.
Chop the apples into small squares and put in a large bowl.
Chop the lettuce and add to the bowl.
Cut the grapes in half and add to the container.
Add the walnuts to the bowl.
Make the vinaigrette with the balsamic vinegar, sherry, salt and pepper and mix until the salt is diluted. Then add the olive oil.
Pour the vinaigrette into the bowl with the salad and mix.
