diff --git a/module/VuFind/src/VuFind/Recommend/SwitchQuery.php b/module/VuFind/src/VuFind/Recommend/SwitchQuery.php
index b1cdc9a786cd86893689a14d8930351a0c75d631..7d77cabf75421481b35ccf23947184d5e6b49547 100644
--- a/module/VuFind/src/VuFind/Recommend/SwitchQuery.php
+++ b/module/VuFind/src/VuFind/Recommend/SwitchQuery.php
@@ -82,6 +82,13 @@ class SwitchQuery implements RecommendInterface
      */
     protected $transforms = array();
 
+    /**
+     * Search results object.
+     *
+     * @var \VuFind\Search\Base\Results
+     */
+    protected $results;
+
     /**
      * Constructor
      *