I am going to try to brew a Russian Imperial Stout with the intent to have something more along the lines of a High Gravity/Desserty type beer similar to Bells Batch 9000. I am using a kit recipe and modifying it with a little less hops, adding cocoa and vanilla bean with bourbon and american oak with lactose for body/sweetness. I am very familiar with alcoholic fermentation because I make wine for a living. I will be kegging this beer and the bourbon will be added post fermentation so no need to warn me on the cautionary ABV. I am trying to sort through all the information in my literature and through the grapevine (literally) what I hear about brewing and I am finding what I would consider mixed information on the use of lactose in beer. I understand lactose's use but I see people adding it to the wort instead of the finished beer. I would think that having a non-fermentable sugar would stress the yeast and risk an incomplete or stinky fermentation. Is lactose normally added before or after fermentation and why? Also, any good videos on all-grain brewing?
IMO there is no need for Lactose in a RIS to start with. The base recipe will bring plenty of body and residual sugars to the the final product.
Lactose doesn't have an appreciable detriment on the yeast during fermentation either. I have never had a beer suffer because lactose was in the ferment. It doesn't slow the yeast down any, nor is there and "stinky" fermentation or poor fermentation. I have always added it in the kettle. Adding later you'd need to dissolve it in some water first and then you'd be diluting your beer some when you finally add it.
Lastly, a pound of lactose in a 5-6gallon batch is the norm.