how to calculate water/grist ratio for pumpkin ale

[jive365]

im doin a pumpkin ale this weekend and i am trying to figure out a grist/water ratio. I am using roughly 5 lbs canned pumpkin puree and 10 lbs grain for a 5.5 gallon batch.
i prefer my mash on the thicker side, say a 1.1 qt/lb ratio. i figure, even after roasting the pumpkin, there should be some residual moisture. do i calculate a ratio with the 5 lbs pumkin in the mix or just beef up the ratio for the grains only. my gut instinct is to beef it up a bit for the grains, but im just curious about other opinions.

 

[swerner]

I just did a pumpkin ale 2 days ago and used a 1.25 qt/lb ratio. I used 4 lbs and I did not factor the pumpkin in at all and the mix was perfect. There is plenty of moisture in the pumpkin. The only thing that I was not sure about is how the pumkin affected the PH. It came in lower than expected.

 

[jive365]

cool,thanks. 1.25 was what i was thinkin. what was your ppg for the pumpkin add? think that might have affected your og? how far off were you?

 

[phoenixs4r]

I just did a pumpkin ale 2 days ago and used a 1.25 qt/lb ratio. I used 4 lbs and I did not factor the pumpkin in at all and the mix was perfect. There is plenty of moisture in the pumpkin. The only thing that I was not sure about is how the pumkin affected the PH. It came in lower than expected.

Very interested as I am starting to use 100% distilled water to brew and do not have a meter. Relying on spreadsheets. Mind posting your recipe and anticipated pH vs actual? Just so I have a baseline to play with.

 

[jive365]

maybe i will just keep my ratio low, 1.1, and see what happens. dont know why i am splittin the atom here anyway. probably wind up with a stuck sparge and have to use the batch for feritilizer. i dont usually measure pH, but i will tomorrow just for scientific chits and giggles.

 

[swerner]

The recipe is from HBT, "Samhain Pumpkin Ale" my room temperature PH came in at 5.3. I expected it to be 5.5. I used AJ's primer in the science section and I'm usually spot on with PH. My gravity came in at 1.046. I have a feeling the pumpkin puree adds a little acidity to the grist. My efficiency is usually closer to 80% but this came in around 73%. All in all the brew day was good and I made beer. If I had it to do over, I would probably nix the 2% acidulated malt and use some lactic acid if my PH came in too high.

 

[periwinkle1239]

The recipe is from HBT, "Samhain Pumpkin Ale" my room temperature PH came in at 5.3. I expected it to be 5.5. I used AJ's primer in the science section and I'm usually spot on with PH. My gravity came in at 1.046. I have a feeling the pumpkin puree adds a little acidity to the grist. My efficiency is usually closer to 80% but this came in around 73%. All in all the brew day was good and I made beer. If I had it to do over, I would probably nix the 2% acidulated malt and use some lactic acid if my PH came in too high.

I had the same issue with my pumpkin brew last weekend. I baked the pumpkin for an hour, not sure if that affected its acidity or not. Either way I think the pumpkin probably does add to acidity and I probably didn't need the 2% of acid malt either. My mash pH was 5.2. Oh and my water content is high in magnesium, sulfates, and bicarbonates so I dilute with 50% distilled water and then add a few grams of CaCl2 since I'm low in calcium. So that additive would've lowered the pH somewhat as well. I'm rambling here, I'm sure it'll be fine...

To answer the original question, don't even factor the pumpkin into your water calcs, it didn't have much of an impact on my final volumes at all.

 

[SpeedYellow]

Use 1.5 quarts per pound for this. You'll get good efficiency and won't have a stuck sparge. A win-win. Worked for me great, with a lower level of pumpkin. Don't forget the rice hulls.

 

[periwinkle1239]

+1 to the rice hulls

 

[jive365]

thank you all for very sound advice. i brew tomorrow and will post my results.

 

[SpeedYellow]

Another thing to consider is adding the pumpkin to the mash late, like just the last 15 minutes. Then you can avoid those ph issues for the most part. And pumpkin has very little starch so there's not much reason to mash it anyway.

 

[jive365]

all in all the pumpkin brew went well. i went with 1.5 qts/lb, 10.6 lbs grain, 5 lbs roasted pumpkin puree. added a lb of rice hulls. mashed at 155 for 115 minutes. fly sparged with 190 degree HL. the mash got EXTREMELY slow after about an hour. had to stir, let settle, and vorlauf again. that seemed to help. took about 1.5 hrs to collect 7 gallons, but i like the slow and steady approach.
OG came in on target, with a factor of 3 ppg for the pumpkin (might be a little low). my efficiency was 84% which is normal for me. i havent bothered with pH at this point so i cannot address how the pumkin affected the acidity of the mash. i added 4oz looseleaf chai tea blend at the end of the boil and it tasted good. subtle pumpkin flavor.

thank you all for your help!

 

[swerner]

Glad things worked out. I can't wait for mine to finish fermenting. I love pumpkin ale.