diff --git a/microdata.module b/microdata.module
index b6961d0..4fe9982 100644
--- a/microdata.module
+++ b/microdata.module
@@ -188,18 +188,25 @@ function microdata_theme_registry_alter(&$theme_registry) {
 function microdata_field_info_alter(&$info) {
   // @todo Add file. This will most likely not be possible until D8, per
   // #1197168.
-  $info['image']['microdata'] = TRUE;
-  $info['list_integer']['microdata'] = TRUE;
-  $info['list_float']['microdata'] = TRUE;
-  $info['list_text']['microdata'] = TRUE;
-  $info['list_boolean']['microdata'] = TRUE;
-  $info['number_integer']['microdata'] = TRUE;
-  $info['number_decimal']['microdata'] = TRUE;
-  $info['number_float']['microdata'] = TRUE;
-  $info['taxonomy_term_reference']['microdata'] = TRUE;
-  $info['text']['microdata'] = TRUE;
-  $info['text_long']['microdata'] = TRUE;
-  $info['text_with_summary']['microdata'] = TRUE;
+  $default_fields_types = array(
+    'image',
+    'list_integer',
+    'list_float',
+    'list_text',
+    'list_boolean',
+    'number_integer',
+    'number_decimal',
+    'number_float',
+    'taxonomy_term_reference',
+    'text',
+    'text_long',
+    'text_with_summary',
+  );
+  foreach ($default_fields_types as $field_type) {
+    if (array_key_exists($field_type, $info)) {
+      $info[$field_type]['microdata'] = TRUE;
+    }
+  }
 }
 
 /**