Looking at Eric's post on Smoke effecting Rennet's action on curd formation...It won't. Rennet is an Enzyme, Chymosin, that causes one of the Proteins in milk, Casein, to coagulate into curds. Enzymes are Chemicals somewhat similar to Acid. They can be destroyed or inactivated by Heat but Cold Smoke should have Zero if not very limited affect on their action, however, I don't know all the chemical properties of Smoke. Now, the Smokes affect on any Bacteria added to curd to establish the assorted flavors and types of cheese may very well be a different story. I would say for the basic homemade Fresh Cheeses like mozzarella, Cream, and Cottage Cheese as well as the Acid coagulated Ricotta, the smoking of the Milk or Cream should only add flavor and extent the shelf life in combination with any salt added. Which by the way is why Salt is added to Butter.
For all reading this...Home made Butter that does not contain Salt will have a limited Fresh Tasting Shelf Life. It will not kill you but after 3-4 days you will notice a quickly increasing Off Taste or Souring. This is because although the cream was originally Ultra Pasteurized the whipping effect of the food processor also whips airborne Bacteria into the newly formed Butter. Some Bacteria, Lactobacillus, is deliberately added to Butter in parts of Europe because while it adds a Sour/Fermented taste to Butter it is very effective at inhibiting other harmful bacteria or bacteria the cause spoilage. So make small batches, add salt or with time we will see if the Smoke extends the shelf life. Wrap your butter well as butter is extremely good at picking up flavors from the refer or freezer. For an additional flavor twist, you can wrap your butter in Fresh Herbs, sliced Onion, sliced Garlic or go crazy and add a slice of Blue Cheese, then remove them after a day or two. All will add a " Hint " of flavor without the Punch that mixing a Compound Butter would have...JJ