What would happen...

Most likely, 6 lbs. of DME would be far too much for a single 2 or 3 gallon batch of your typical beer.

A beer that big would also require a big starter, which would require more DME.

You'd only need like 3 or 4 lbs. - What style are you interested in brewing?

 

Save it for yeast starters or higher gravity all grain batches...or gravity correction

 

This is good thinking.

 

Well, consider this:

3.5 gal boil / 2.5 gal batch / 60 minute boil

3 lbs. Briess Light DME alone would put you at about 1.052 OG / 1.013 FG.

An entire quart of maple syrup must weigh a couple lbs. - Put it on a scale. Let's say it weighs 3 lbs. That's 50% maple syrup in your recipe which gives you less of a beer, and more of a malt beverage. Not to mention, it bumps you up to about 1.088 OG / 1.022 FG. Typically, I would think that maple syrup additions would be treated like honey, and added at flameout or high krausen in the 5-15% range... certainly not 50% though.

 

6 lbs of DME and a qt of maple syrup in a 3 gallon batch would give you a maple barleywine with an OG of about 1.120.

 

I would probably do some sort of a 10 gallon partial mash...or split it between my next two five gallon batches (partial mash).

Starters make sense, but it would take a while to get through 6#.

 

Damn you HB42! Just when I am trying to think sensibly you go and make me wish I had 6lbs of DME laying around.

 

The sugars in maple syrup are 100% fermentable. Final gravity would not be increased one bit by adding it.

 

Do tell how this one comes out!

 

Plug the numbers into any brewing software and tell me what you get for FG with 3 lbs DME vs. 3 lbs DME plus 3 lbs. maple syrup. In the past, I've personally added (not supplemented) 8 to 16 oz. corn sugar to otherwise the same exact recipes and experienced slightly increased gravity each and every time. That's fully fermentable too, but even so I experienced increased gravity, I'm under the impression that there are more complex sugars in real maple syrup vs. storebought, and perhaps small amounts of other stuff in the product are not fully fermented out. On another note, I think using 50% maple syrup would affect the typical beer yeast with low alcohol limits. So a portion of this maple syrup wouldn't be fully fermented out by the yeast with a probable cap of 10% abv.

 

Some brewing software does not account for the different fermentability of different adjuncts. It typically applies some default value for the particular yeast used to everything. So it will be wrong for simple sugars. The numbers you posted mean that the sugars in Maple Syrup are only 75% fermentable. That's simply wrong.

The sugars in maple syrup are glucose, fructose, and sucrose. All are 100% fermentable.

 

There are no complex sugars in maple syrup, it's mostly sucrose with small amounts of invert (glucose and fructose). Also, 6 lbs of DME and 1 qt of maple syrup is not 50% maple syrup.

 

That still doesnt explain why two identical recipes, one with corn sugar vs. one without... brewed by the same brewer, both with the same amounts/varieties of 2-row, DME, wheat, carapils, same amount of hops added at the same time, with the same size/type of yeast starter, same ferm schedules, times, temps, volume, etc. ended up with 1.014 FG (without corn sugar) vs. 1.017 FG (with corn sugar). Those were my most recent results. But I've done this multiple times because I buy ingredients in bulk and have really enjoyed my go-to recipes. Never once did adding (not supplementing) corn sugar to an otherwise identical recipe maintained the same FG as the recipes without it. It was always slightly increased. I take rigorous notes, so I would've noticed that.

I never said it was. See above. I said "let's say" that 1 qt. of maple sugar weighs 3 lbs. - I dont have 1 qt. of maple syrup to verify weight. But if I did, and used it in conjunction with 3 lbs. DME (not 6 - never said that either)... then would that be 50/50?

 

Google+wiki answers tells me it would be 2 pounds.

 

The recipe being discussed in this thread is 6 lbs of DME and 1 qt of maple syrup, not 3 lbs of DME and 1 qt of maple syrup.

 

Do you guys ever read? I used a "for instance" because I thought that 6 lbs plus 1 qt was too much to use in an approx. 2.5 gallon batch. See below for a refresher.

 

I'll actually answer my own question and say that yeast age/viability was the cause. In each case, I added corn sugar to the wort with older yeast.

But what about if in the OP's case, he went for the 50/50 or 60/40 or 70/30 (DME to Maple Syrup) ratio for his recipe? Hypothetically, wouldn't the yeast stop working at one point when the alcohol exceeds the yeast's threshold? Thus, you'd be left with a beer higher in FG than expected. That was my whole point here. I understand what you're saying about it being 100% fermentable. I was just trying to find out why this didn't align with my findings (which I just answered after thinking about it). And also if it would be the case for the OP if there was "too much" of a 100% fermentable source in a particular recipe, i.e. the yeast stopped working after only fermenting 75% of the fully fermentable sugars?