Adding Extract Late

What is the result of adding half the extract later in the boil? ie - I've got 6 ibs of dry light malt extract and 1 ibs of 30L crystal. I was planning on steeping the crystal for 30 min / then adding 3 ibs of the extract at 60 min / then add the other 3 ibs extract at 30 min.

Also, I know the longer hops boil the more bitterness. But at about 20 min added is that aroma and then at about 10 min is that flavor? And what is the bitterness/flavor/aroma of dry hopping? THanks.

Let's start with the first one... You can add your malt extract later in the boil. This is referred to a late malt addition. This is usually done within the last 15 minutes of the boil to ensure pasturization and will result in a slightly lighter beer. On the same note, the hops utilization will go down slightly due to a lower gravity boil for the first 45 minutes. You may want to compensate a little with your bittering hops (first addition) to make up for this lower gravity.

Regarding the hops usage, the first hops in the kettle during the boil will add the bittering of the hops to your beer. The 20 minute and 10 minute additions will result in more of a hops aroma and flavor. All hops added at flameout (right after the boil) or used in dryhopping will really contribute a lot to the aroma of your beer.

In extract brewing, a late malt addition is typically done to prevent caramelization of the extract as well as the darker colors associated with extract brewing (particularly LME) as oppose to grain. The idea is that extract has already been boiled/pasteurized once and is shipped that way, and so boiling more than 15 minutes doesn't do much except resanitize (or is it sterilize?) it. You do a small addition from the beginning because boiling hops in low gravity water (water without the extract) makes the hops harsh and/or diminished hops utilization.

Thanks - very helpful...One last question. THis is my first time using grains at all.

Like I said, I am just seeping, but the steeping sock, does it need to be steralized or does the heat from the boil kill everything nasty? I assume the boil would suffice?

You do not need to sanitize the sock because you will be boiling everything after the steep. I think you will like the results of late extract addition. Have fun brewing!

If I do the late edition of the extract, how much will I need to compensate for the bittering hops? My original recipe calls for .70 oz at 60min?

10% less hops is an okay starting place. Play with it; opinions vary from "same amount" to about 20% less, and the science isn't well understood at the moment (it's an area where home brewers are just starting to catch up with commercial brewers in understanding the science, and the commercial brewing thoughts may not apply precisely to the relatively tiny homebrew scale).

Wait now I'm confused. Previous posters made it seem like I would need to add hops if I did a late extract addition. So do I add or subtract hops?

If anything, late extract will increase hops utilization meaning that you should decrease the amount you use.

Ya that makes sense because bittering hops, off set the malt right?