My non-scientific DME darkening test - w/ pic comparison

Since I've seen many state DME darkens with a longer boil, and I haven't experienced it, I thought I'd do a quick test today. It's by NO means scientific! I only had 2 lbs of Briess Wheat DME available so this is what I did:

I brought 1 gallon of water to a boil, shut off the heat, and stirred in 1lb of DME. I then brought it back to a boil and timed 10 minutes. Then I shut off the heat and cooled it in the sink. After cool I took a pint glass sample.

Next, I brought 1 gallon of water to a boil, shut off the heat, and stirred in 1lb of DME. I then brought it back to a boil and timed 60 minutes. Then I shut off the heat and cooled it in the sink. After cool I took a pint glass sample.

Now, I know I know, the best approach would be to have boiled one gallon of water for 50 minutes then added the DME for the 10 minute test - BUT, I didn't have the time to test for nearly 3 hours so I did it this way. The results are pretty similar anyway because at the end I also compensated for the boil off.

The first pic shows the two pint glasses next to one another. The one on the left is the 10 minute boil. The one on the right is the 60 minute boil. Take note how they really aren't worlds apart in darkness and you can see the 60 minute one is more opaque, hence adding to a darker appearance, due to the boil off. If I had done a 50 minute boil off for the 10 minute test I am fairly certain the results would match identically. The second pic shows the 60 minute boil with top off water to get it back to 1 gallon. This is a bit unfair since I don't know what the boil off was for the 10 minute boil but it couldn't have been too much so I didn't take it into account. Though as a result you can see the pint on the left (the 10 minute boil) is ever so slightly darker so a mismatch in the top off water is likely the reason.

Again, this test was NOT meant to be scientific or definitive proof of anything. I just did this out of curiosity and so far from my past batches it seems to agree with my personal opinion that DME does not really darken more for a full length boil - or if it does it's rather negligible. Oh, btw... the hefe on the left is a 5.5lb (5 gallon batch) all Wheat DME hefe I made. Just put it there to show the color after fermenting.

Only gonna bump this once since it's about to get buried back on page 2 and I put some time into it. Thought maybe someone would find this at least mildly interesting


Rev.

I like it. I'd heard the same thing about extract in general but never really thought to test it. I guess I don't worry about style much so color is whatever it comes out to be. I think your methods are sound, and while not perfectly univariable my vote is, if it's replicable, that this serves as a fine guide of 'it don't matter how long ya boil, just boil!'. Kyle

I see this didn't get much attention at the time, but i'll say thanks for doing it....i'm moving to full volume boils after having done many partial boils with late extract addition. I couldn't work out if I should be adding all my extract up front when doing full volume, having heard about this darkening problem. Now i've read this i'll try (i'm using LME rather than DME), and if I think it comes out any darker i'll do a 60/40 up front/late addition next time and report back.