Hello @SteveAgl and welcome to our forums 
First of all the previous comment was probably a spam (e.g. not a real person posted it) but for now as I am not very sure, I’ve just flagged the answer so don’t worry too much about ironic comments for now 
Now for your initial question, the answer is a bit more complicated but I will try to make it as easy as possible. As summary what you are trying to do is not possible out of the box currently (to take the setRelation string and manipulate it with callbackColumn). Let me explain.
setRelation is basically changing the type of your field to “relation” so trying to change the field type to a callback it doesn’t do the change that you wish for. To simply say it, when you are trying to do a callbackColumn to the setRelation you take the id as an output and not the full string to manipulate it.
A quick solution that I can think for your problem is the below:
To use the fieldTypeColumn function that is based on the fieldType but it will also require a query to your database from laravel.
So the solution that we are looking for is this:
$crud->fieldTypeColumn('ingrediente_id', 'dropdown_search', [
'52' => 'salt',
'64' => 'sugar',
....
]);
Of course replace the hardcoded array with the ids should come from your database with a custom query model from your database that you will get the above output.
I hope the above helped.
Regards
Johnny