diff --git a/actionpack/lib/action_dispatch/http/response.rb b/actionpack/lib/action_dispatch/http/response.rb
index a370c3f082c01c3db5b8fe7c5dcf2cc03358ce99..d1e1f1fcf625f4616afcd6bd317056df29a66723 100644
--- a/actionpack/lib/action_dispatch/http/response.rb
+++ b/actionpack/lib/action_dispatch/http/response.rb
@@ -188,8 +188,7 @@ def content_type=(content_type)
     # information.
 
     def content_type
-      type = parse_content_type.mime_type
-      type && type.to_s
+      parse_content_type.mime_type
     end
 
     def sending_file=(v)