In most casual upscale restaurants, I would guess that average bar (alcohol) sales are probably about 25-30% of the total sales. As with food cost the bar has several factors that need to be taken into in order for anyone to properly manage the costs costs of a bar. They include good purchasing practices, proper pouring of drinks, a good draft beer system, proper storage of wine, eliminating theft and making sure your bartenders are ringing everything up and not stealing from you.
This is an area that you absolutely do not want to over purchase any high end wine or liquor as these tend to run several hundred dollars and are slow movers. That is a lot of money sitting on the shelf and unnecessary inventory on hand can lead to miscounts and theft. Track your purchases and utilize your product mix reports when placing purchases.
Ensuring the bartenders are properly pouring drinks is essential. I use a marked wine glass with either tape or a measured amount of water next to the area the bartenders are pouring drinks so they use it as marker when pouring actual wine. If you use jiggers it is important to make sure the bartenders are using them on every drink and they must know their recipes to use the proper jigger size. If you are a free pour bar as we are, then the bartenders must complete a pour test sheet so you can see how accurate they are on different size pours. They must also know their recipes. Over pouring kills you liquor cost while under pouring kills your business as weak drinks will not bring your guests back.
It is important to have a good draft beer system complete with keg savers. I have found that Keg savers help prevent air getting in the lines by allowing you to bleed the line after tapping a new keg. This helps prevent the 3-4 pitchers of foam that is poured off after each keg and believe me, this ads up and some beers pour off more that 4 pitchers of beer. I also like to use the Beer Blast system that makes Nitrogen from the outside air. It replaces the Nitrogen tanks that you need for Guinness and also mixes a little bit into your regular kegs that I have found helps to ensure they are empty. (It is important to keep a back up of Nitrogen just in case the system goes down, but this has not happened to me in 5 years in three different restaurants) How many times have you thought the kegs were tapped to early as you shake the empties feel what seems to be a lot of beer left in them? This adds up as well.
Improper storage of wine causes it to go bad sooner than it would if it were stored properly.
Theft is a concern in every restaurant and as much as you would like to trust every one you simply can not. I like to keep every thing locked up except what is in my back bar. If you have an overnight cleaning crew, it is important to keep an eye on your draft beer as that is a perfect opportunity for them to steal beer. I have heard and seen some keg handle locks, but have personally never used them.