diff --git a/lib/jbuilder.rb b/lib/jbuilder.rb
index 1290839..d6e3867 100644
--- a/lib/jbuilder.rb
+++ b/lib/jbuilder.rb
@@ -344,9 +344,11 @@ def _set_value(key, value)
   end
 
   def _map_collection(collection)
-    collection.map do |element|
+    collection = collection.map do |element|
       _scope{ yield element }
-    end - [BLANK]
+    end
+    collection.delete(BLANK)
+    collection
   end
 
   def _scope