AdBlue® is not made of pigs urine! AdBlue® is a mixture of 32.5% Urea and Water but extremely pure versions of both. The Urea required is manufactured from Natural gas to a technical specification and looks like a white grain (a little like salt). This is mixed with deionised water (water that has been stripped of elements dissolved within it) and the mixture is then heated to ensure it dissolves.
The manufactured batch is then sent to a lab to test it against the VDA specification for AdBlue®. Only when the lab certifies that it meets the required standard is the AdBlue® dispatched to the customer, and the container will show the batch number of that AdBlue®.
The confusion with pigs' urine comes as AdBlue® does contain Urea, which is found in urine (both pigs and humans) but at very low levels – it can't be used to make AdBlue®!