Prepare 12 muffin forms, greasing them in advance and optionally placing paper muffin cups in them. Using a fork, mix the cream cheese, orange zest, yoghurt, sugar, oil and egg. Stir until you get a uniform mixture.
Separately, sift the flour, add the salt, baking powder and the dry ingredients in 2-3 lots to the liquid ones. Stir well with a fork, finally add the blueberries and distribute them in the muffin forms. The mixture should be about 2/3 of the height of the forms.
Bake the muffins with cream cheese and blueberries for about 20 minutes or until done.