No Conversion of starch to sugar?

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Goose06

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I took biermunchers Centennial Blonde recipe and divided it by 5 to get a 1.5 gallon batch from his original 5.5 batch. I mashed at 155 for one hour in one gallon of water. I then rinsed the grains with a half a gallon of water. I boiled for 60 minutes and did my hop additions as instructed. I cooled the wort to 70 degrees and took a hydrometer reading. The reading was 1.010. Thinking this had to be a mistake I did a test calibration with my hydrometer and it was accurate. All the grains are from More Beer and milled. It appears I was left with almost exactly a gallon of wort so I don’t think the water addition lowered it. This is my third brew and I’m having trouble figuring out what the issue here was.
 

VikeMan

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Is your hydrometer multi-scale (most are)? If so, are you sure you weren't looking at the Brix scale? 10 Brix = 1.040.
 
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Goose06

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What grain did you order, and are you sure that's what they sent you?

How fine (or coarse) was the milling? Were there many whole, uncrushed kernels left in there?

You sure there's a base malt included?
I have 2 row malt, carapils malt, caramel malt, and Vienna malt. I can tell it’s milled, it has a lot of what look to be whole kernels but when I place them in my hand they all are cracked but it doesn’t appear to be as fine as I’ve seen in some YouTube Videos ect.
 

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The best I can think currently is maybe my scale was wrong when I weighed the grains.
Check your scale with a known weight, such as an unopened bag of sugar, or flour, or such.
Or use a container filling with a measured amount of water.

How much grain were you aiming at using?
IIRC, a quart (take-out soup) container holds around 1.5 pounds of unmilled grain.
 
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Goose06

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Check your scale with a known weight, such as an unopened bag of sugar, or flour, or such.
Or use a container filling with a measured amount of water.

How much grain were you aiming at using?
IIRC, a quart (take-out soup) container holds around 1.5 pounds of unmilled grain.
Just checked my scale with a pre measured bag of priming sugar. It read 5.1 ounces when the bag is labeled as 5oz. I converted the 5.5 gallon recipe into a 1.5 gallon recipe and the total weight of the grains was around 2 pounds.
 

IslandLizard

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it has a lot of what look to be whole kernels but when I place them in my hand they all are cracked
You mean when you squeeze those whole looking kernels between your thumb and index finger they pulverize? If so, that's good, they're indeed crushed. Now the pieces may still be relatively large, but most should be no larger than 3/32".

Did you put the grains in a mesh bag when mashing? Then stir well? so the whole content gets thoroughly hydrated. Did you check the temp after stirring and during or after the mash?
A small volume can lose heat quickly, dropping below 140F, where conversion activity starts to cease.
 
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Goose06

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You mean when you squeeze those whole looking kernels between your thumb and index finger they pulverize? If so, that's good, they're indeed crushed. Now the pieces may still be relatively large, but most should be no larger than 3/32".

Did you put the grains in a mesh bag when mashing? Then stir well? so the whole content gets thoroughly hydrated. Did you check the temp after stirring and during or after the mash?
A small volume can lose heat quickly, dropping below 140F, where conversion activity starts to cease.
I did all of those things but I just tested the calibration of my thermometer compared to my digital thermometer and it is off between 5-8 degrees. If I held the mash temp between 150-155 per that thermometer. It was at 150 the majority of the mash so realistically it was probably between 142-145. Could that have caused the issue?
 

IslandLizard

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I did all of those things but I just tested the calibration of my thermometer compared to my digital thermometer and it is off between 5-8 degrees. If I held the mash temp between 150-155 per that thermometer. It was at 150 the majority of the mash so realistically it was probably between 142-145. Could that have caused the issue?
One of the best ways to keep a (small) mash pot warm is putting it inside a warmed up but turned off oven.
Wrapping insulation (thick blanket, sleeping bag, etc.) around the pot (including the bottom and lid), helps keeping the mash temps too.

At 142-145F conversion will take place but it takes much longer. Alpha Amylase (chopping starch chains into smaller pieces) becomes inactive below 140F.
Enzyme Activity in Mash.jpg
 

IslandLizard

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A small volume can lose heat quickly, dropping below 140F, where conversion activity starts to cease.
[Quoting myself]
The good news is, inside the narrow "Brewers Window," between 146-158F, the mash proceeds rather quickly as soon as the grist gets hydrated. It could be 70-80% done in 10-15 minutes, especially if the grist is finely milled, and the mash is not overly thick or thin. 1.25-1.75 quarts of water per pound of grain is a good starting thickness.
 
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Goose06

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One of the best ways to keep a (small) mash pot warm is putting it inside a warmed up but turned off oven.
Wrapping insulation (thick blanket, sleeping bag, etc.) around the pot (including the bottom and lid), helps keeping the mash temps too.

At 142-145F conversion will take place but it takes much longer. Alpha Amylase (chopping starch chains into smaller pieces) becomes inactive below 140F. View attachment 781613
Great advice thank you! I would think this is probably the issue since I did get some conversion with a reading of 1.01. Best part about the small batch is I have lost much and I have enough to make it again today. I’ll let you know how the second round goes.
 

IslandLizard

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Great advice thank you! I would think this is probably the issue since I did get some conversion with a reading of 1.01. Best part about the small batch is I have lost much and I have enough to make it again today. I’ll let you know how the second round goes.
Ah, good!
Measure the gravity at the end of the mash. It should be around what you'd expect, and quite a bit higher than the projected OG, as you haven't sparged yet.

The other thing one could do to prove the mash was successful and completed is performing a residual starch test with half a teaspoon of wet grist on a white saucer (or plate) and a drop of Iodine. If the grist (the pieces of grain) turns blue it still contains starch, and the mash should be continued. There are precise instructions around on how to do that test.

You can get a small 1 oz bottle of Iodine tincture at your local pharmacy for $1-2 or so. Local homebrew stores may also have them.
It's the same Iodine one would use for disinfecting small scrapes and cuts, so it's dual purpose. ;)
 

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Do you normally take pre-boil gravity readings? If not, it might be good to start. Then you would be able to notice something like an extremely low gravity before you start the boil. Then you could try to correct it with malt extract, sugar, or maybe even attempt to reintroduce the grain to the wort and try to continue mashing. I have no idea if the latter of those would work, it's just a thought.

Refractometers are great for checking gravity during and after the mash, in my opinion.

Also, you may find helpful an equation I use to determine what my preboil gravity should be. If I find that my preboil is lower than what it should be, I can add malt extract to hit the OG I'm targeting.

Pre-boil Gravity = post boil gravity * post boil volume /pre boil volume

You use whole numbers for specific gravity in the equation, 1.050 would be 50, for example.
 
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No adjustments.
FWIW, I put the full recipe into Brewers Friend's mash/water calculator (link). Assuming no data entry errors (and modeling the water as just RO water), the mash pH appears to be at the very high end of the range (or maybe just beyond).

For pale beers with no mineral water, a small amount of acid or acidulated malt to bring the pH down towards the middle of the range. Something to keep in mind if efficiency continues to be lower than 75-ish%.
 

hotbeer

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I recommend you do the iodine test for starch conversion too on your next attempt.

And as soon as you get mashed in, do a test right away so you can see what it looks like when you have a high ratio of unconverted starches.

Then the later test that shows or should show most everything completely converted won't be as confusing.

However I still wonder if you had everything scaled correctly and possibly just diluted your wort too much.
 

grampamark

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This seems unlikely, given that the caramel and Carapils would be a small percentage of your recipe, but by way of eliminating one more probable cause for your low OG I have to ask.

Were the grains you weighed for this batch weighed separately or had the grist for the larger batch size already been combined and you weighed out 20% of that combination? It would take a pretty significant amount of stratification of the mixed grains for this to be the cause, but I suppose stranger things have happened. :cool:
 
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Goose06

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This seems unlikely, given that the caramel and Carapils would be a small percentage of your recipe, but by way of eliminating one more probable cause for your low OG I have to ask.

Were the grains you weighed for this batch weighed separately or had the grist for the larger batch size already been combined and you weighed out 20% of that combination? It would take a pretty significant amount of stratification of the mixed grains for this to be the cause, but I suppose stranger things have happened. :cool:
they are in individual bags and I weighed them separately.
 
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Goose06

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Ah, good!
Measure the gravity at the end of the mash. It should be around what you'd expect, and quite a bit higher than the projected OG, as you haven't sparged yet.

The other thing one could do to prove the mash was successful and completed is performing a residual starch test with half a teaspoon of wet grist on a white saucer (or plate) and a drop of Iodine. If the grist (the pieces of grain) turns blue it still contains starch, and the mash should be continued. There are precise instructions around on how to do that test.

You can get a small 1 oz bottle of Iodine tincture at your local pharmacy for $1-2 or so. Local homebrew stores may also have them.
It's the same Iodine one would use for disinfecting small scrapes and cuts, so it's dual purpose. ;)
Ah, good!
Measure the gravity at the end of the mash. It should be around what you'd expect, and quite a bit higher than the projected OG, as you haven't sparged yet.

The other thing one could do to prove the mash was successful and completed is performing a residual starch test with half a teaspoon of wet grist on a white saucer (or plate) and a drop of Iodine. If the grist (the pieces of grain) turns blue it still contains starch, and the mash should be continued. There are precise instructions around on how to do that test.

You can get a small 1 oz bottle of Iodine tincture at your local pharmacy for $1-2 or so. Local homebrew stores may also have them.
It's the same Iodine one would use for disinfecting small scrapes and cuts, so it's dual purpose. ;)
I have figured out the issue, I was ready the scale i have wrong. I was supposed to be using 1.5LBS of 2 row and was using 15 ounces. That translated Into all of the grain measurements. Of course I couldn’t get any gravity, nothing in there to convert to sugar!
 

marc1

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I did all of those things but I just tested the calibration of my thermometer compared to my digital thermometer and it is off between 5-8 degrees. If I held the mash temp between 150-155 per that thermometer. It was at 150 the majority of the mash so realistically it was probably between 142-145. Could that have caused the issue?
Another point to consider:
What size was the grain bag relative to the mash tun?
If you are mashing and not steeping, you want the bag to be as big as the whole tun. You do not want much water outside of the bag, which will reduce efficiency. The grain should be free floating and loose in the mash, not tied up tight in a ball.
 

IslandLizard

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I was supposed to be using 1.5LBS of 2 row and was using 15 ounces.
That answers some of the low gravity, but...

Your 2-row alone was supposed to be 1.5lbs = 24 oz
You only used 15 oz

1 pound of 2-row should yield around 32 points in 1 gallon (32 ppg) at 85% mash/lauter efficiency.
If the mash went well with full conversion, that still should have given you 15/24 * 32 points/gal = 20 points in 1 gallon, or a gravity of 1.020, after the boil. Not 1.010.
And it should be a bit higher than 1.020, since there were other grains in the mash too, also contributing gravity.

So your mash process definitely needs some close attention.
 

DBhomebrew

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5.5/5 is 1.1 not 1.5. Makes sense it’s watered down.

Batch size of the original recipe is 5.5, not total water volume. OP hit it fairly close.

It appears I was left with almost exactly a gallon of wort

That said, what is "almost exactly a gallon". 0.9? 1.1? That's a 10% variance up or down.

With a straight-sided pot, a stainless ruler, and the formula for the volume of a cylinder, one can get fairly accurate volumetric data.

Be sure to adjust for temperature expansion. That's only 2.5-4%, but every little bit of pencil sharpening counts when troubleshooting your system/process.
 
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VikeMan

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Batch size of the original recipe is 5.5, not total water volume. OP hit it fairly close.



That said, what is "almost exactly a gallon". 0.9? 1.1? That's a 10% variance up or down.

With a straight-sided pot, a stainless ruler, and the formula for the volume of a cylinder, one can get fairly accurate volumetric data.

Be sure to adjust for temperature expansion. That's only 2.5-4%, but every little bit of pencil sharpening counts when troubleshooting your system/process.

All good points. I never cease to be amazed, though I really shouldn't be anymore, by how many seemingly experienced brewers either just guesstimate the volume, or worse, don't pay attention to it at all, and then report either terrible or impossibly high mash efficiency numbers based on just the gravity.
 

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Batch size of the original recipe is 5.5, not total water volume. OP hit it fairly close.



That said, what is "almost exactly a gallon". 0.9? 1.1? That's a 10% variance up or down.

With a straight-sided pot, a stainless ruler, and the formula for the volume of a cylinder, one can get fairly accurate volumetric data.

Be sure to adjust for temperature expansion. That's only 2.5-4%, but every little bit of pencil sharpening counts when troubleshooting your system/process.
Must be my Canadian math but he's off by over 25%. without measurement error his OG could be 1.025 just by the math mistake alone. Add some estimation volume error and you get to his SG pretty fast.
 

hawkwing

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Care to share your math?
I googled his original recipe and it’s said OG 1.041. I looked up 1.040 on an SG chart and it’s 108g/L sugar. So if your grain is supposed to give you that but you are using (1.5-1.1)/1.5=26.7% less grain. You’ll have 1.1 us gal = 4.16 L you’ll have 4.16 L * 108 g/L = 450 g then divide that but the actual batch size of 1.5 gal which is 5.68 L gives 79.2 g/L. Looking that up on the SG chart gives between 1.025 and 1.030.
 

IslandLizard

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Of course I couldn’t get any gravity, nothing in there to convert to sugar!
15 oz of (American) 2-row can easily convert its own weight in additional non-diastatic adjuncts. Very likely quite a bit more, as its DP is in the 80-110°Lintner range, depending on the maltster and barley used.

As long as the average grist DP is above 35°Lintner, it should completely convert. But it may need some extra time when it's in the lower range.
 

hawkwing

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If you guys dropped the freedom units for metric you wouldn’t have this problem. Lol so easy to make mistakes with units. A decimal system is way better. Although even in Canada I can’t think of my height and weight in anything but feet and inches and pounds and have it mean something to me. And most recipes are still in cups and spoons.
 

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If you guys dropped the freedom units for metric you wouldn’t have this problem. Lol so easy to make mistakes with units. A decimal system is way better. Although even in Canada I can’t think of my height and weight in anything but feet and inches and pounds and have it mean something to me. And most recipes are still in cups and spoons.

You should see my brew day spreadsheet. Imperial and metric all mixed up. The height of the wort in mm, spits out a volume in gallons. Grain weight in pounds, hops & salts in grams.
 

IslandLizard

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If you guys dropped the freedom units for metric you wouldn’t have this problem. Lol so easy to make mistakes with units. A decimal system is way better. Although even in Canada I can’t think of my height and weight in anything but feet and inches and pounds and have it mean something to me. And most recipes are still in cups and spoons.
I'm not arguing that, but use the system and methods you're most comfortable with and stick with it.

There's also the sense of "feedback" one should respect. For example, when you mix your grain into the strike water and it looks quite a bit thinner (or thicker) than previous batches, a bell should start ringing in the brain that something is different and perhaps off. So don't ignore such warnings.

A refractometer is a very useful instrument for quick gravity checks during a brewing day, and also to check on fermentation progress, as it only takes one or two drops, not a measuring tube 1/2 to 3/4 full of wort/beer. That counts even more so with small(er) batches.

Another issue with small batches is that even small deviations in ingredients (and environment) can have a much larger impact compared to larger batches. For example, the recipe scaled down to 1 gallon needs 2 oz of some crystal or specialty malt, but a (small) weighing error of only 0.5-1 oz will change that recipe balance much more than the same amount (of error) would have in a 5 gallon batch.
 

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If your pale 2-row was mid-weighed were the rest of the grains also shorted?

This could very easily account for what you’re experiencing.
 
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Another issue with small batches is that even small deviations in ingredients (and environment) can have a much larger impact compared to larger batches. For example, the recipe scaled down to 1 gallon needs 2 oz of some crystal or specialty malt, but a (small) weighing error of only 0.5-1 oz will change that recipe balance much more than the same amount (of error) would have in a 5 gallon batch.
With the right scale(s), this isn't an issue. :mug:
 

bracconiere

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Looking that up on the SG chart gives between 1.025 and 1.030.
If the mash went well with full conversion, that still should have given you 15/24 * 32 points/gal = 20 points in 1 gallon, or a gravity of 1.020, after the boil. Not 1.010.


sorry i meant to quote those in the opposite order....
 

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One of the best ways to keep a (small) mash pot warm is putting it inside a warmed up but turned off oven.
Wrapping insulation (thick blanket, sleeping bag, etc.) around the pot (including the bottom and lid), helps keeping the mash temps too.

At 142-145F conversion will take place but it takes much longer. Alpha Amylase (chopping starch chains into smaller pieces) becomes inactive below 140F. View attachment 781613
A 170 degree oven works too. I usually get my strike water to 160, mash in, cover and let the temp drop to 148 (takes 15-30 min), then pop it in the oven for the rest of the time. Temp might raise a degree or two.
 
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