Retrieving post content before it's processed


I’m trying to query a post’s content (from a widget) to check if a shortcode is present in the content:

I’m using a simple loop:

$args = "showposts=".$posts_number."&cat=".$blog_category;
$the_query = new WP_Query( $args );
while ( $the_query->have_posts() ) : $the_query->the_post();

Inside the loop, I’m using this code to test if I got the code but it doesn’t show any results (its blank):

$content = $post->post_content;
echo $content;

Does anyone know how to get the pre-processed post code from a widget?