Does adding extract late in boil affect quality?

Hello Everybody

So Ive seen a lot of recipes that call for adding some DME or LME in the last 15 minutes of the boil. I assume this is so you dont have to use as much hops to get a certain IBU level. Is there a downside to doing this? I feel like there must be.

Thanks

Late extract addition can also help keep your beer a lighter color as extract brews can tend to be darker than one would like. No downsides to the late additions that I'm aware of.

edit: I guess a downside could be an overly bitter beer if you don't adjust your bittering hops.
A general guideline when doing late extract additions is to cut your bittering hops by 25% or so.

Now downisde because the extract doesn't need to be boiled for an hour. 10 minutes or so is enough to sterilise it if that concerns you and just being in 100dge C wort will help dissolve it. That's the main reasons you add it to a boil at all (presuming the boil is already around 1040).

Of course it affects gravity though - gravity is a measure of the density of liquid and sugars affect the density of liquid. You are adding more sugar to liquid - gravity goes up. You should take that into account in the recipe development so if your recipe is significantly above 1040, you make up the wort to 1040 then add the remainder in at the end. If it's around the 1040-1050 range mark just boil with it all. Anything up to 1050 I wouldn't worry.

Just to add to what Tom777 said, the more extract that is in your boil for the full duration, the more likely you are to carmelize some extract. This can possibly effect final gravity, and of course color and flavor as stated above. Out of habit and for repeatablility (sp?), I always do late additions, and it saves hops!

Papazian has a Hop Utilization Chart in TCJOHB that recommends keeping your lbs of DME equal to your gals of water; i.e., 1 gal and 1 lb, 2 gals 2 lbs, etc., for maximum bitterness extraction.

Deviating from that one way or the other means you should adjust your hops. Too much malt equals a dense wort and low hop bitterness extraction, too much water tends to make not only more bitter, but gives it a harsh (versus mellow) bitterness, IMO.

I boil for 45 mins and turn the heat off. Then add 1 lb od DME at a time and dissolve it before adding the next pound. Then I let it sit for the last 15 mins.

I've been using this formula since 1994.

Interesting. When I get home next month I will try this as well. Thanks for the input!