Cherry is a tricky wood that is prone to "splotching", due to the variable permeability of the grain. That is most evident when it comes to using stains on it. Many other woods are that way too. (Pine seems to be the worst.) That makes for many headaches for furniture makers.
When I've made cherry furniture, I've used a dilute mixture of hide glue (that stuff really stinks) and water sprayed over it to seal things. You can also use a very dilute mixture of lacquer to do the same thing, but beware; if it is too concentrated, it will seal the wood and prevent the next stain layer from being absorbed at all--splotching in reverse. For that reason I typically try to avoid staining cherry and go with the traditional lye / water treatment when working in it. Light also darkens cherry (and many other woods) over time.
There are a zillion forums and articles out there on the various wood working sites for much greater information, but remember, each piece of wood is a little bit different, and your mileage will vary, so experimentation on your actual piece of wood (I suggest the adjacent scrap from the sides of the barrel, or, if that isn't available, in the barrel channel--someplace that won't show on the finished piece) is a prudent (and I think fun) thing to do.
