Save meta value as an array of arrays

If you don't need to query on the data, you can pass arrays directly to the post meta functions, WordPress will automatically serialize/unserialize the data for you.

$your_array = array(
   array(
    'title' => 'something',
    'price' => 'something',
   ),
   array(
    'title' => 'something',
    'price' => 'something',
   ),
);

update_post_meta( $post_id, 'your_key', $your_array );