diff --git a/src/UnitOfWork.php b/src/UnitOfWork.php
index 5c16c511ce1..e1336140640 100644
--- a/src/UnitOfWork.php
+++ b/src/UnitOfWork.php
@@ -1557,18 +1557,15 @@ public function addToIdentityMap(object $entity): bool
      */
     final public static function getIdHashByIdentifier(array $identifier): string
     {
+        foreach ($identifier as $k => $value) {
+            if ($value instanceof BackedEnum) {
+                $identifier[$k] = $value->value;
+            }
+        }
+
         return implode(
             ' ',
-            array_map(
-                static function ($value) {
-                    if ($value instanceof BackedEnum) {
-                        return $value->value;
-                    }
-
-                    return $value;
-                },
-                $identifier,
-            ),
+            $identifier,
         );
     }