Back to Yuengling, the former production manager, John Houseman, used to give us homebrewers excellent tours of the Tampa plant. Although they used to use a cereal cooker, that is no longer part of their process. They have a mash press in the older brewhouse, but not sure if they use it in their newer, bigger one.
He gave me the recipe once for both the Lager and the Porter so that I could blend them and make Black and Tan. The adjunct he used was "high maltose corn syrup" (his words) and he gave me a sample - turned out to be 12 pounds - from a silo out by the train spur. I miss that guy.
The other adjunct they were using was a coloring agent similar to sinamar to make each batch consistent.