Using field api to get key of select list option I need the safe output of a key from a select list field within a field collection item.

I'm theming a field collection item and one of the fields is a select list like:

icon-map|Map
icon-info|Info
icon-pencil|Pencil


I'm using the following to create some easy to use variables;

$fields = array_keys($content);
foreach ($fields as $field) {
  $field_items = field_get_items('field_collection_item', $content[$field]['#object'], $field);
  $$field = render(field_view_value('field_collection_item', $content[$field]['#object'], $field, $field_items[0]));
}


This works fine for all fields except for the select list.  I need the key of that select list.  For this select list field, $field_items is an array which looks like:

array(1) { [0]=&gt; &amp;array(1) { ["value"]=&gt; string(13) "icon-map" } }


However, $field_icon (result of $$field = render(..) ) is Map, which makes sense.  

I can get the key by using $field_items[0]['value'] but I'm not sure that's the best way.
I hope this may help

 $key = $form_state['values']['whatever'];
$options = list_allowed_values("field_whatever");
$value = $options[$key];