检查laravel中数据库中序列化数组中的值

Question

I have a database where i have multiple "shoutouts". Each of these can have multiple hashtags.

In the database it looks like this:

a:2:{i:0;s:6:"#hello";i:1;s:6:"#world";}

I am trying to create a function where I find each shoutout that has a specific keyword, for example all shoutouts that have a hashtag #world

I want to go trough all shoutouts and check if they have the keyword in the array.

public function shoutoutSpecific($hashtag) {
        $hashtag = '#' . $hashtag;
        $shoutoutsIn = Shoutout::get();

        foreach($shoutoutsIn as $shoutout) {

          $hashtags = unserialize($shoutout->hashtag);

          //add to a new object 'shoutouts' if it has the keyword

          }

        return view('shoutout', compact('shoutouts'));
    }

I don't know what to do with the data I have unserialized from the database to check if the array contains #world. The serialized data is stored as shown above.

How do I check if the data I unserialized have #world in it?

All help much appreciated!