How to use lemons?

Ok, I have been doing some research in how to incorporate lemons when making beer, but i still have some questions.

What is the difference between using real lemon, and just lemon juice I buy from the store?

How would I use a real lemon? Some people say to grate the rinds. So I need to take a grater to the outside skin of the lemon? How much of the rind can you use? Does the rind really contribute flavor? This is something I would not have thought of. Initially, I imagined one would squeeze out the lemon juice from the lemon itself. You don't use any of the "interior" of the lemon?

Right now I can only do extract beers. So assuming using rinds of the lemon is the way to go, I have read that boiling fruits is never good. Do I steep the rinds in a seperate pot, at say, 150 F for 20 mins, and add that directly to the primary fermenter once the wort has cooled in there? What about sanitation concerns?

Lots of questions, I know. However, the third beer I ever made I thought I was good enough to incorporate grapefruits rinds. Out of 12 beers, that was the only one to fail. I had spider webs of bacteria strands in my bottles. I am getting ready to try a similar recipe for a contest, and can't afford another disaster

Any details would be much appreciated!

First off, what kind of beer are you trying to make with lemon?

I'd think the only style suitable to use lemon in would be a wit--possibly a hefe. So that said, I'll answer questions as to what I've heard or read in the past. Use the lemon zest only. That is the yellow covering on the outside of the lemon. You can use a zester to shave it off. Only take that yellow covering--AVOID the white rind material as it is bitter, and you don't want that in the beer. Add the zest to the boil or add it to the fermenter.

I heard this info on an episode of "The Jamil Show" on the brewing network (www.thebrewingnetwork.com) for Wit beer styles.

FWIW, I wouldn't add straight juice to a beer, but that's me.

I would think the acidity of the juice would inhibit the yeast, at least in the quantities you would need for the juice to influence the flavor. The flavor is more potent in the rind, anyway.

also, this may be obvious, but is worth mentioning since your grapefruit brew got infected...

wash the lemons before you zest them.

Definately recommmend washing since there is probably insecticides on the rind anyway.

I recently did a batch similar to a blue moon. I added zest of one orange (with corriander) at 10 min (remaining) and zest from a second orange (with the remaining corriander and hops) at flame out and steeped for 10 min prior to cooling.

Avoid the white pith under the rind. It will cause excessive bitterness, so I've heard.

If you add the zest to the boil and forget to wash the lemons i dont think it will matter as tbe boil will kill anything on there and i dont think the insecticide will infect the beer, but i would imagine it would impart a horrible flavor.

I "dry hopped" my wit with lemon peel and it turned out very nice. I just took the peel of 1 lemon (washed of course) and put it into the secondary. It imparted quite a bit of lemon/citrus flavor, which suprised me for it being a 5 gallon batch. I've listened to the Jamil show above (assuming it is the one where Doc talks about massive piles of zest). In my opinion, a zester is a huge PITA. Just try a vegetable peeler. It usually peels off just deep enough to get the rind without getting into the white pith. You can then cut the strips up and a bit and not have to deal with the zester.