Your recipes have a serving amount associated with them but you don't actually scale recipes when viewing them. You scale your recipes while you build a service for a customer.
Here is an example of a service:
The first column after the name of the recipe is number of servings associated with that recipe. You can simply place your cursor in that box and enter whatever number of servings you'd like and press enter. Once you do this, the ingredients will display the scaled amounts on both your grocery list and on the production report for this service.