[jquery] JQuery refresh select box

I am populating a select field using JQuery on page load using this method

 $('#select').append('<option value="' + result + '">' + result + '</option>'); 

However this leaves the select box 'blank', i.e the first value in the options list is not preselected as the selected option.

How do I 'refresh' this list so that the first value is preselected?

Sorry - should have said it was JQuery mobile before

Thank you.