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Old 09-14-2013, 04:23 PM   #51
Aug 2013
Posts: 3

aomagman78, I used a similar method. I shredded 8lbs in a food processor, held at 152F for 1 hr with 2 gal, drained the 2 gal, then added one more, boiled for 30 min and then "mashed the potatoes" added everything back in and held at 152F another 1hr this time with some alpha and beta amalyse. my OG for the gallon I had left after boil (after the massive fallout) was 1.030. when I use numbers like yours, assume 25% starch, that puts me around 37%. also, there was WAY too much potatoes left. i'm not sure where I went wrong. let me know how yours works.

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Old 11-20-2014, 03:55 AM   #52
Aug 2014
Posts: 13

I purchased some white milet malt and after a couple of experiments I determined it was not properly malted and could only convert about 75%.
Also I wanted to make a millet Chestnut ale similar to a brown English ale.

The Chestnut chips where given a rest at 122 for 8 hours with Pectin and Amalyse enzyme added,
I Ran 5 lbs of Sweet potato in my food processer to a course grind so it wouldn't create a stuck mash.
I just wanted the Enzymes and was not concerned about extracting the sugars or starch from the potatos.
I put the sweet potatoes in an oven set to 145, inside a turkey bag. for 4 hours
I then meshed my grains using the Chestnut extract at 150, and added the sweet potato mash. Then let it rest for 90 minutes. At this point it passed the Iodine test.
Note: I peeled the sweet potatos and added additional Alpha Amalyse to the mash. Perhaps the soapy flavor comes from the Skins.
Also I did not try to gelatinize the sweet potatoes

Recipe - 4 gallons
6 lbs Millet Malt
1 lb Oat Malt
1/2 lb Sprouted Quinoa (From Whole foods)
The above grains where given a 122 protein rest for 30 min
4 lbs Med Chestnut chips
5 lbs Course Ground Sweet Potatoes
1 tsp alpha amalyse enzyme
All the above where Mashed at 150 for 90 minuites Then passed Starch test
Used RO water (similar to distilled) for the above, PH was 5.4
Sparged with RO water
Steeped 30 min @ 150, with 1 gal. Med hard water, 1 lb Millet Crystal, 1 lb Med Toasted Buckwheat both about 90L, PH 5.6) and added to boil
Did typical 60 min boil with hops added @ 60, 15, 5
Irish Moss @ 15
Pre Boil volume 5 gallons, Final Volume 4 gallons
OG 1.052
IBU 16
SRM about 15

The Sweet Potato worked well to complete the starch conversion. I tried a similar recipe w/o sweet potato and ended up with over 2 oz of starch per gallon.
Taste test of wort, malty, earthy, caramel, coffee, smoky with bitter, nutty after taste.

I noted a lot of people here where giving the sweet potatoes a protein rest at 122, not sure why as sweet potatoes are very low in protein, I do not believe this accomplishes anything.

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Old 11-20-2014, 10:36 AM   #53
glutarded-chris's Avatar
Jul 2013
New Smyrna Beach, Florida
Posts: 361
Liked 88 Times on 64 Posts

The use of sweet potatoes is very interesting! Curious why you steeped the crystal and buckwheat separately rather than just mashing with the rest of the grain.

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Old 11-20-2014, 05:16 PM   #54
Mar 2013
Harrisburg, PA
Posts: 606
Liked 61 Times on 57 Posts

Originally Posted by glutarded-chris View Post
The use of sweet potatoes is very interesting! Curious why you steeped the crystal and buckwheat separately rather than just mashing with the rest of the grain.
Maybe to help prevent a stuck sparge because of the buckwheat. He wasn't in gel range for the buckwheat anyway so he wasn't going to get much from it.

Curious where the oat malt cam from. AiH?
To drink the best, we have to brew the best!
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Old 11-21-2014, 10:41 PM   #55
Feb 2013
burlington, ontario
Posts: 33
Liked 3 Times on 3 Posts

I don't brew gf however after reading this thread i wonder if a 50-50 mash of raw adjunct and sweet potato as an enhanced double decoction would enter into the realm of delicious?

mash in around 35c @ 3L/KG, draw off 60-70% of the mash liqour and boil the **** out of the mash then add back to bring it through the mash range over the course of an hour.

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Old 11-25-2014, 03:28 PM   #56
Aug 2014
Posts: 13

I only wanted the color and flavor from the crystal and buckwheat. I also was using a lot of buckwheat seed which have the hulls. not just grouts, so I didn't want the tannins. That is why I steeped separately.

I don't think Sweet Potato has much Alpha enzyme. It has some just under its skin and has a lot of beta enzyme through out it's meat. Also many reported brewing with sweet potato resulted in a soapy taste where they used unpeeled and then gelatinzed them. I peal my sweet potato and don't bother to gelatinize. I also add alpha enzyme. Seems to have good conversion power without off flavors. I don't know the DP of sweet potato, so I can't say if it can convert 50% adjunct. If I wasn't doing GF or low gluten I would use 6 row instead of sweet potato and use a protein rest for the adjuncts.

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Old 09-01-2015, 04:26 PM   #57
Sep 2015
Posts: 2

Depending on your use of the sweetpotato you may not need to mash it. If you roast it, you needn't mash it. When you roast the sweetpotato, what you are essentially doing is mashing it, only with dry heat instead of in water. The only real purpose of the water in the mash process is to distribute the enzymes for contact with the starches and collect the resulting sugars. Roasting the sweetpotato temperature activates the amylase enzymes and converts the starches to fermentable sugars. The best yields are going to come from starchy varieties, like the yellow or cream-fleshed specimens. The normal table-fare (typically beauregard) won't yield as well, but will give you a more familiar flavor.

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