Why add extract in two stages?

[emersonc]

So I have been brewing for about a decade but have not made an extract batch for about 8 years (been all grain for a while). I am opening up a u-Brew in Olympia, Wa so I need to brush up on my partial extract brewing skills. I see a lot of recipes that add half of the LME/DME just before the boil starts and the other half at the end. Why? Why not just add all of the extract at the beginning?

Do you want to add liquid first then dry later? Does it matter if it is DME vs LME?

Thanks

 

[Hoosierbrewer]

It has already been boiled once. You need some for the hops and the other grains that you may have used. Some beers are darker when you boil extract longer since there may be caramelization. Look at this link for better explanation


http://www.midwestsupplies.com/what-is-late-extract-addition-brewing.html.

 

[emersonc]

Interesting, I had no idea that it would increase the hop utilization. It seems like it would depend on the type of beer you are brewing. Late addition may be good for lighter beers because this would reduce the scorching and camelization of the malt. But at the same time you would have to reduce the amount of hops used due to the increased hop utilization.
If I were to brew a stout, porter or brown ale adding all of the extract at the beginning would be good because these beers tend to benefit form the carmelization process and have low bittering hops.

I am sure there is more to it then just this and I will look into the late extract additions.

 

[emersonc]

found this also..

http://beersmith.com/blog/2008/02/20/better-beer-with-late-malt-extract-additions/

 

[Yooper]

Interesting, I had no idea that it would increase the hop utilization. It seems like it would depend on the type of beer you are brewing. Late addition may be good for lighter beers because this would reduce the scorching and camelization of the malt. But at the same time you would have to reduce the amount of hops used due to the increased hop utilization.
If I were to brew a stout, porter or brown ale adding all of the extract at the beginning would be good because these beers tend to benefit form the carmelization process and have low bittering hops.

I am sure there is more to it then just this and I will look into the late extract additions.

No, you really don't have to consider hops utilization. What matters in extract batches with lowered hops utilization has more to do with a boil size than the wort gravity. Many extract brewers will start with, say, 2.5 gallons, in the boil because they have a smaller pot or burner. That is what reduces the IBUs, as adding 50% water will dilute the IBUs 50%.

In a full boil, where you start with 6.5 gallons of wort, excess maillard reactions (not a true caramelization as it doesn't get hot enough) are not really a factor whether the extract is added early or late. Maillard reactions are those that contribute to darkening, similar to when someone uses bread and makes toast. Those browning reactions are Maillard reactions. You do get a ton of Maillard reactions in a condensed boil with a lot of sugar, so that would be the reason to add the bulk of the extract at the end of the boil if doing a partial boil.

 

[Calder]

No, you really don't have to consider hops utilization. What matters in extract batches with lowered hops utilization has more to do with a boil size than the wort gravity. Many extract brewers will start with, say, 2.5 gallons, in the boil because they have a smaller pot or burner. That is what reduces the IBUs, as adding 50% water will dilute the IBUs 50%.

This doesn't make sense. Maybe I need to read it again. Why does a smaller pot affect IBUs, if you say wort gravity doesn't.

Yes, I have read about the supposed max IBUs you can get (and that is a different argument where I don't completely agree with you), but if brewing say a 35 IBU beer with only half the volume, what does the volume have to do with final IBUs if gravity is not a player in it?

 

[Cyclman]

This doesn't make sense. Maybe I need to read it again. Why does a smaller pot affect IBUs, if you say wort gravity doesn't.

Yes, I have read about the supposed max IBUs you can get (and that is a different argument where I don't completely agree with you), but if brewing say a 35 IBU beer with only half the volume, what does the volume have to do with final IBUs if gravity is not a player in it?

Solubility. If you have a smaller volume of liquid, with double the hops, they will be less soluble than double the liquid with the same amount of hops.

 

[Yooper]

Solubility. If you have a smaller volume of liquid, with double the hops, they will be less soluble than double the liquid with the same amount of hops.

It's more than that, though.

There IS a maximum amount of hops oils that can isomerize- generally said to be 100 IBUs or so, but even one of the most highly hopped commercial beers, Pliny the Elder, has been tested at 85 IBUs (it calculates out to 250+). So many of the experts that have written papers about this claim it's more like 85 IBUs, rather than 100.

So, even if you were able to get 100 IBUs in 2.5 gallons of wort, for the sake of argument, and you diluted it with 2.5 gallons of water (0 IBUs), that means 50 IBUs as a max (even if that were possible).

It's not a big deal for a cream ale or a light lager, but for an IIPA, that does matter. Oftentimes, that is why extract brewers claim their beer is too sweet in the finish- it's underbittered due to a partial boil.

At this point, we've gone off of the topic too far, and the maximum hops isomerization and solubility is a better topic for the Brew Science forum, but here is a link and except and a reference for that topic: http://beer.suregork.com/?p=2377

The limiting factors include the poor solubility of the alpha-acids, the reaction rate of the isomerization, and the reaction rate of the degradation of iso-alpha-acids. Prolonged boil times (over approximately two hours) do not increase the iso-alpha-acid content of the wort, since after this the rate of iso-alpha-acid degradation exceeds that of alpha-acid isomerization, and the iso-alpha-acid starts to decrease. Hence, the maximum amount of bitterness one can get from a 60-minute boil addition (independent of the size of the addition) is approximately 50 IBU (see this Basic Brewing Podcast and http://hwcdn.libsyn.com/p/f/9/b/f9b...18566032&hwt=01e66b96fa2138d7a832d1cc94f522b0). If one thrives for a higher bitterness, it must be achieved from a combination of hop additions.

 

[unionrdr]

I was going to add that I increased boil volume in my 5 gallon kettle (pb/pm biab) from 2 1/2G to 3 1/2 gallons. I add no more than 2-3 pounds of plain DME in AE beers for the normal amount of hop additions, whatever the recipe might be. All LME or remaining DME at flame out. Cleaner flavor & lighter color results. Hop Hop flavors also got a tad better in the boil by adding them loose, rather than using muslin hop socks as I previously did. This seems to give the hop flavors a bit more "edge", to put it that way, than using the hop socks. But I also use the 10 1/4" dual layer fine mesh strainer commonly available from Midwest & NB to pour the chilled wort through into the FV. This aerates the wort as well as cleaning it.

 

[WoodlandBrew]

In Malowiki's thesis on isomerization of alpha acids in a model sort boiling system he has a nice chart depicting the solubility limit of alpha acids in beer on page 53. It correlates with others findings and matches the solubility that yooper noted.