Serialize Options

serialize.html.erb

#If you have  config1 as serialize parameter it store hash than
# serialize :config1,Hash

<%= form_tag(@user_config) do |f| %>
 <%= text_field_tag "user_config[config1][test2]" %>
 <%= text_field_tag "user_config[config1][test1]" %>
  <%= submit_tag %>
<% end %>

# Now you have an array

<%= form_tag(@user_config) do |f| %>
 <%= text_field_tag "user_config[][config1]" %>
 <%= text_field_tag "user_config[][config1]" %>
  <%= submit_tag %>
<% end %>