diff --git a/lib/paperclip/storage/delayeds3.rb b/lib/paperclip/storage/delayeds3.rb
index 2016a0c..0276406 100644
--- a/lib/paperclip/storage/delayeds3.rb
+++ b/lib/paperclip/storage/delayeds3.rb
@@ -196,7 +196,7 @@ module Paperclip
         end
         paths.each do |style, file|
           log("saving to s3 #{file}")
-          content_type = style == 'original' ? instance_read(:content_type) : file_content_type(file)
+          content_type = style == :original ? instance_read(:content_type) : file_content_type(file)
           s3_object = self.class.aws_bucket.object(s3_path(style))
           s3_object.upload_file(file,
                                 cache_control: "max-age=#{10.year.to_i}",
@@ -217,7 +217,7 @@ module Paperclip
         end
         paths.each do |style, file|
           log("saving to yandex #{file}")
-          content_type = style == 'original' ? instance_read(:content_type) : file_content_type(file)
+          content_type = style == :original ? instance_read(:content_type) : file_content_type(file)
           s3_object = self.class.yandex_bucket.object(s3_path(style))
           s3_object.upload_file(file,
                                 cache_control: "max-age=#{10.year.to_i}",
@@ -238,7 +238,7 @@ module Paperclip
         end
         paths.each do |style, file|
           log("saving to sbercloud #{file}")
-          content_type = style == 'original' ? instance_read(:content_type) : file_content_type(file)
+          content_type = style == :original ? instance_read(:content_type) : file_content_type(file)
           s3_object = self.class.sbercloud_bucket.object(s3_path(style))
           s3_object.upload_file(file,
                                 cache_control: "max-age=#{10.year.to_i}",