A question about a recipe: Uncle Fester on a Fasta' Vespa (espresso-chocolate gelato, Roman style)

I have a question about step 8 on the recipe "Uncle Fester on a Fasta' Vespa (espresso-chocolate gelato, Roman style)" from pierino. It says:

"Make gelato. For Fester that means, with the motor running, pouring in the mixture and letting it run for twenty or twenty five minutes until it reaches gelato texture. You will know when it's ready---trust me." what motor??????????