diff --git a/app/code/Magento/ConfigurableProductGraphQl/Model/Variant/Collection.php b/app/code/Magento/ConfigurableProductGraphQl/Model/Variant/Collection.php
index d34d6f8a5dfab..11c22e9ff5e6f 100644
--- a/app/code/Magento/ConfigurableProductGraphQl/Model/Variant/Collection.php
+++ b/app/code/Magento/ConfigurableProductGraphQl/Model/Variant/Collection.php
@@ -51,7 +51,7 @@ class Collection
     /**
      * @var StockConfigurationInterface
      */
-    protected $stockConfig;
+    private $stockConfig;
 
     /**
      * @var MetadataPool