Remove a field in a structure

I have an struct created from an xml file:

Parameters.Processing.EnableFilter.Text = true
Parameters.Processing.CutoffFreq.Text = 3000
Parameters.Classification.Threshold.Text = 0.95

I want to remove the field .Text and have a struct similar than:

    Parameters.Processing.EnableFilter = true
    Parameters.Processing.CutoffFreq= 3000
    Parameters.Classification.Threshold = 0.95

This is the most similar thing I could find but it is not doing exactly what I want.

newName = '';
oldName = 'Text';
[a.newName] = a.(oldName);
a = rmfield(a,oldName);