<h2>Tasting</h2>
  <%= form_for @tasting do |f| %>
    <% if @wine.color == 'red' %>
      <%= render 'red_wine' %>
    <% else %>
      <%= render 'white_wine' %>
    <% end %>

    <%= hidden_field_tag :event_wine_id, @event_wine.id %>
  <%= f.submit %>
  <% end %>

<h2>Tasting</h2>
  <%= form_for @tasting do |f| %>
    <% if @wine.color == 'red' %>
      <%= render 'red_wine' %>
    <% else %>
      <%= render 'white_wine' %>
    <% end %>

    <%= hidden_field_tag :event_wine_id, @event_wine.id %>
  <%= f.submit "Submit" %>
  <% end %>

Change text on button to Submit
Change text on button to Submit
