2qt./LB Mash...

[Kaiser]

Doesn't the extract yield analysis of the malt pretty much indicate the maximum efficiency you can get from a malt? Maybe I don't understand the science correctly but if that is true than anything over that optimum value (whatever the analysis is) can't be done.

This all goes back to the concept of "good enough" which applies to mashing. In essence this means that malt has enough enzymes to convert far more than its own starch under optimal conditions. As a result conditions can still be suboptimal and still lead to a complete starch conversion.

In the congress mash the pH may not be optimal but that is compensated for by having a very fine crush which is made with a disc mill spaced only 0.2 mm appart (8 mil). And the mash is also quite thin (starts with about 2 qt/lb and ends with about 2.5 qt/l) and stirred.

In brewing we don't strive for the optimum for starch conversion. We target a desired fermentability and try to make sure that the efficiency is good enough. Luckily the conditions that that attenuation target requires can easily be within the range of "good enough" for max starch conversion.

Really light malts like pils have a distilled water mash pH of 5.7 and you need to add a lot of calcium or some acid to get it to 5.4 and below. I add about 70 ppm Ca to my Pilsner water and then use ~2-3% acid malt in the grist to get the pH to 5.3-5.4.

Kai

 

[menschmaschine]

Since temperature "regulates" enxyme activity, do certain pHs or range of pH favor alpha-amylase over beta or vice-versa? For example, and using single infusion mash temperature at the mid-point between beta and alpha rests, would a pH at the lower end of optimal range better stimulate alpha or beta activity over a pH at the upper end of the optimal range?

 

[Kaiser]

Yes, there is a slight difference between the optima for b and a-amylase. But the difference is very small (~0.2 units). Interestingly enough my experiments showed that the attenuation optimum is at a higher pH than the efficiency optimum which is the other way around from what is reported in the literature. But this is very much within the error of the results and the experiments were not designed to give results of the precision required for this.

But the effect of temperature is larger and as a result it is much easier to control attenuation through temperature than to control it through the pH.

Kai

 

[cactusgarrett]

I tried the thinner mash, to an extent, this weekend. Typically i use 1.25qt/lb and this time went with 1.75. 12.5lbs pilsner and 0.5lbs cara-pils. I used damn near 90% DI water and 5.2 stabilizer (and a pH check confirmed 5.2) - so i don't think my mash chemistry was too far off of "normal" to affect things.

Typically with 1.25 i get around 70% efficiency into the boiler, but this time hit only around 66% with 1.75. I, of course, had to cut back my double batch sparge volumes to smaller than i would have liked (~6.75qts each), but felt comfortable doing so based on Kai's comments on a higher quality first runnings.

Based on this info, i'm falling back on the idea that my sparging & lautering processes are where i'm losing efficiency, as opposed to conversion. If anyone's interested i can post gravities of the full process later, as i usually take readings of each running, as well as pre and post-boils.

 

[Kaiser]

If anyone's interested i can post gravities of the full process later, as i usually take readings of each running, as well as pre and post-boils.

I'd be interested in the numbers. The 4% drop can easily come from the reduced sparging, but I'm curious why the thinner mash didn't boost your conversion efficiency.

Kai

 

[The Pol]

I fly sparge.

 

[cactusgarrett]

The 4% drop can easily come from the reduced sparging, but I'm curious why the thinner mash didn't boost your conversion efficiency.

Kai

Yeah, i figured what i'd lose in sparging i'd gain back from the (what i thought was going to be) increase in conversion. I'll post the numbers later today when i can get to them.

 

[menschmaschine]

I used damn near 90% DI water and 5.2 stabilizer (and a pH check confirmed 5.2) - so i don't think my mash chemistry was too far off of "normal" to affect things.

Just curious, is this the first time you used 90% DI water?

 

[cactusgarrett]

I've done it before, as i've made a czech pils before. My local water is VERY hard so i used 1gal of local water and 9gal of DI water to match Pilzen's profile. Typical brews I use only around 5 or 6gal of DI and 3 or 4gal of city water.

 

[cactusgarrett]

I'd be interested in the numbers.

Okay, here are the specifics:

12.5lb pilner malt
0.5lb cara-pils
1.75qt/lb (22.75qt strike)
153F sacc rest for 60min
2 sparges of 2.5gal each (to reach 170F)
1st runnings = 1.060
2nd runnings = 1.037
3rd runnings = 1.022
pre-boil = 1.045 (1.053 target for 70%)
7gal boil, 5.5gal final vol (90min boil)

Let me know if you're interested in any other details.


garrett

 

[Kaiser]

Okay, here are the specifics:

12.5lb pilner malt
0.5lb cara-pils
1.75qt/lb (22.75qt strike)
153F sacc rest for 60min
2 sparges of 2.5gal each (to reach 170F)
1st runnings = 1.060
2nd runnings = 1.037
3rd runnings = 1.022
pre-boil = 1.045 (1.053 target for 70%)
7gal boil, 5.5gal final vol (90min boil)

Let me know if you're interested in any other details.


garrett

Your 100% conversion first wort gravity would have been around 1.073. You got only 1.060. This makes for a conversion efficiency of 60/73 = 82% which is a bit low. 18% of the starch didn't convert in the mash.

But your pre-boil numbers don't make sense. 7 gal @ 1.045 is 7*45 / (12.5 *36 pppg) = 70%. But you say that you got only 66%.

70% eff. into kettle and 82% conversion efficiency means that your lauter efficiency was about 85%. This is what I would expect from batch sparging 12 lb of grain twice.

So your problem is that your thin mash doesn't convert as well as your thick mash. I have been claiming that the opposite should be true. Odd how this didn't work for you. Was the recipe the same as the recipes that you mashed thick?

Kai

 

[JVD_X]

Your 100% conversion first wort gravity would have been around 1.073.

Kai - how is that calculated?

 

[Kaiser]

Kai - how is that calculated?

You'll have to use the plato scale, which is basically the weight % of the extract in the wort. And it works best when working with metric:

13 lb = 5.85 kg malt which has ~80% extract: 4.68 kg

He is using 22.75 qt = 21.5 l = 21.5 kg water

If all that extract is dissolved in all that water the wort strength in Plato will be:

100% * 4.68 / (4.68 + 21.5) = 21.1 %Plato

or 1.084 SG

Ooops, this doesn't really match up with my table and with what I said before. Let me run the numbers again and see if I have a bug in my table.

Kai

 

[JVD_X]

You'll have to use the plato scale, which is basically the weight % of the extract in the wort. And it works best when working with metric:

13 lb = 5.85 kg malt which has ~80% extract: 4.68 kg

He is using 22.75 qt = 21.5 l = 21.5 kg water

If all that extract is dissolved in all that water the wort strength in Plato will be:

100% * 4.68 / (4.68 + 21.5) = 21.1 %Plato

or 1.084 SG

Ooops, this doesn't really match up with my table and with what I said before. Let me run the numbers again and see if I have a bug in my table.

Kai

Yep - I got 1.082 in beersmith with 100% conversion.

 

[Kaiser]

Let's try again:

13 lb = 5.90 kg; at 80% extract potential this is 4.72 kg of extract

22.75 qt = 21.53 l = 21.53 kg water

So the weight percentage of the extract dissolved in that water is:

100% * 4.72 / (4.72 + 21.53) = 18.0 %Plato

This is 1.074 SG

My table is correct. JVD_X, if you do this with Beersmith you cannot use 22.75 qt as the resulting volume since the dissolved extract actually expands the volume of the water. That's why this calculation cannot be done as easily with the pppg based method. The expansion is about 0.075 gal/lb of dissolved extract. In this case 0.78 gal. This brings the total wort volume on the mash tun to 6.46 gal. With 36 pppg and 13 lb I get a gravity potential of 72 points.

No change necessary to my other posts.

Kai

 

[JVD_X]

Let's try again:

13 lb = 5.90 kg; at 80% extract potential this is 4.72 kg of extract

22.75 qt = 21.53 l = 21.53 kg water

So the weight percentage of the extract dissolved in that water is:

100% * 4.72 / (4.72 + 21.53) = 18.0 %Plato

This is 1.074 SG

My table is correct. JVD_X, if you do this with Beersmith you cannot use 22.75 qt as the resulting volume since the dissolved extract actually expands the volume of the water. That's why this calculation cannot be done as easily with the pppg based method.

No change necessary to my other posts.

Kai

But - the grain absorbs about 1.9 gallons of water or so (@ 0.15 gallons per pound) that reduces your water to 14.33 kilograms.

so 100% * 4.72 / (4.72 + 14.33) or 24.7 plato or 1.105

Again - I probably don't understand the science.

 

[Kaiser]

But - the grain absorbs about 1.9 gallons of water or so (@ 0.15 gallons per pound) that reduces your water to 14.33 kilograms.

so 100% * 4.72 / (4.72 + 14.33) or 24.7 plato or 1.105

Again - I probably don't understand the science.

The "water" absorbed by the grain is actually wort and has the same gravity as the rest. Maybe some water that actually penetrates into the husks is just water, but that doesn't amount to 0.15 gal/lb.

Kai

 

[cactusgarrett]

But your pre-boil numbers don't make sense. 7 gal @ 1.045 is 7*45 / (12.5 *36 pppg) = 70%. But you say that you got only 66%.

I was just going by what Beersmith gave me for my Efficicency into Boiler based on the numbers i plugged in. I didn't hand calc anything.

...about 85%. This is what I would expect from batch sparging 12 lb of grain twice... So your problem is that your thin mash doesn't convert as well as your thick mash.

What do you recommend i do in the future, then, if bumping to 1.75qt/lb didn't show an increase (taking into account loss of sparge efficicency)?

 

[Kaiser]

I was just going by what Beersmith gave me for my Efficicency into Boiler based on the numbers i plugged in. I didn't hand calc anything.

Beersmith is right and I was wrong. I forgot to compensate for the expansion of the wort at boiling temps. It is 4% lager than at room temp and thus the efficiency appears 4% higher. 66% is correct and I also get this when I multiply the 7 gal with 0.96.

What do you recommend i do in the future, then, if bumping to 1.75qt/lb didn't show an increase (taking into account loss of sparge efficicency)?

This brings us back to looking at the parameters in the mash and the most promising would be a finer crush, given that your pH is in an acceptable range. Do you have control over the crush?

Aside from that, do you check for iodine negative wort at the end of the mash? How long do you mash for and at what temp?


Kai

 

[slimer]

So Kai, I was trying to figure this out yesterday. If you have the Lintner of the malts in a mash, is there a formula that you can plug in to know how long you need to convert the starches?

This is the example I was trying to figure out. They are presented in percentage of the mash and degrees Lintner
40% of (Wheat Malt @ 74 deg Lint)
30% of (Vienna Malt @ 50 deg Lint)
20% of (15% Flaked Wheat & 5% Honey Malt @ 0 deg Lint)
10% Honey (Not in Mash)

My main fear is that if I do a 122 deg Protein Rest for 20 Mins and a 60 Min Sacc Rest at 150, the Vienna and the Wheat malts do not have enough diastic power to convert the Flaked Wheat and the Honey Malts.

This is at 1.5 qt/lb, but with my new system, I would probably be increasing the ratio.

I found this formula, but I don't know how it/if applies.

 

[cactusgarrett]

This brings us back to looking at the parameters in the mash and the most promising would be a finer crush, given that your pH is in an acceptable range. Do you have control over the crush?

Sort of, and no. I use my LHBS's mill, but i double crush EVERYTHING. Doing this, I've never gotten above 72 or 73%.

Aside from that, do you check for iodine negative wort at the end of the mash? How long do you mash for and at what temp?

I have never checked for conversion via iodine test. I guess it would be worth investigating, huh? I sacc rest for at LEAST 60min around 154F (give or take a couple degrees depending on style) for every batch. Are you thinking i should be resting for longer?

 

[Kaiser]

So Kai, I was trying to figure this out yesterday. If you have the Lintner of the malts in a mash, is there a formula that you can plug in to know how long you need to convert the starches?

No. At least none that I know of and even if there was one it would be full of parameters that you would have difficulties to measure precisely enough. Because of that we can only turn to science for guidance in what to expect qualitatively by to get quantitive numbers we need to turn to experience.

Home brewers are unique in the fact that they want to brew a lof of different styles and want to be able to make their best shot with the first batch. So they expect to calculate a lot upfront. It may work with color and to some extend with hop bitterness, but attenuation and level of conversion speed are things that we have to dial in.

This is the example I was trying to figure out. They are presented in percentage of the mash and degrees Lintner
40% of (Wheat Malt @ 74 deg Lint)
30% of (Vienna Malt @ 50 deg Lint)
20% of (15% Flaked Wheat & 5% Honey Malt @ 0 deg Lint)
10% Honey (Not in Mash)

My main fear is that if I do a 122 deg Protein Rest for 20 Mins and a 60 Min Sacc Rest at 150, the Vienna and the Wheat malts do not have enough diastic power to convert the Flaked Wheat and the Honey Malts.

This is at 1.5 qt/lb, but with my new system, I would probably be increasing the ratio.

There are rules of thumb about the average diastatic power of an infusion mash. I don’t know exactly what the number is, but you might be pushing it with your 35 Linter mash. Either add ~20% 2-row or make sure you keep checking for conversion and keep the 2-row at hand to throw it in if the mash doesn’t want to get iodine negative.

Doughing in at low temps helps the enzymes as they can hydrate before they hit the more stressful higher temps.

Kai

 

[slimer]

There are rules of thumb about the average diastatic power of an infusion mash. I don’t know exactly what the number is, but you might be pushing it with your 35 Linter mash. Either add ~20% 2-row or make sure you keep checking for conversion and keep the 2-row at hand to throw it in if the mash doesn’t want to get iodine negative.

Doughing in at low temps helps the enzymes as they can hydrate before they hit the more stressful higher temps.

Kai

35 Lintner? I got ~49 Lintner. Since the honey isn't in the mash wouldn't the calculation be (4/9)*74 + (3/9)*50 = 48.67 Lintner?

I have never done the iodine test, so I wouldn't know what to compare it with. I have watched your decoction video and have seen you do it, but have no practical experience.

 

[Kaiser]

35 Lintner? I got ~49 Lintner. Since the honey isn't in the mash wouldn't the calculation be (4/9)*74 + (3/9)*50 = 48.67 Lintner?

You are correct. I typed the wrong numbers into the calculator.

I have never done the iodine test, so I wouldn't know what to compare it with. I have watched your decoction video and have seen you do it, but have no practical experience.

There is some info here: http://braukaiser.com/wiki/index.php?title=Starch_Test

While you may get away without the test when making an all barley beer, once you are pushing the disastatic power, you should use this test to make sure that you don’t get starch or very long dextrines into the kettle.

Kai

 

[slimer]

Thanks. My nerdiness got the best of me yesterday and I was wandering around confused.

 

[Coastarine]

I tried a 1.5qt/lb mash today up from my usual 1.25. I saw slightly lower than average efficiency. I'll probably keep doing what I used to do.

 

[The Pol]

I tried a 1.5qt/lb mash today up from my usual 1.25. I saw slightly lower than average efficiency. I'll probably keep doing what I used to do.

As stated before... if you have near 80% eff. you will probably see no increase, maybe a decrease. If your MASH efficiency is lacking you will see an increase. Doing a thinner mash you will most likely hurt your lauter efficiency through the use of less sparge water. SO if your MASH eff. is already great, you will see no increase, maybe a decrease due to the loss of lauter eff. If your mash eff. is lacking, you will see an increase due to the fact that this method improves the mash eff. only.

Clear it up?

 

[Coastarine]

As stated before... if you have near 80% eff. you will probably see no increase, maybe a decrease. If your MASH efficiency is lacking you will see an increase. Doing a thinner mash you will most likely hurt your lauter efficiency through the use of less sparge water. SO if your MASH eff. is already great, you will see no increase, maybe a decrease due to the loss of lauter eff. If your mash eff. is lacking, you will see an increase due to the fact that this method improves the mash eff. only.

Clear it up?

I broo beer real good.

Yeah, thanks.

 

[KerryD]

Probably a dumb question, but I've been thinking about it after following this thread and seeing the diagram of where the desired wort lies when mixed with water.

If you were using this method and let's say you were more or less hybrid sparging... why wouldn't you use an extra half gallon of water in the sparge and stop the runoff when you reached your desired preboil volume?

For all practical purposes wouldn't you have pushed through a more desirable wort?

 

[pinarphan]

I'm making the switch to all grain after 10 years! I've spent the last couple of weeks cramming info into my head and one source was archived brewing network shows. In 2006 the Sunday show did an interview with Denny Conn and he has an interesting method. (dennybrew) He wants the first run off to be half of the total boil volume and the sparge to be half. So he mashes at 1.25/lb but then 10-15 minutes before the end of the mash he adds boiling water to bring the mash up to the 50% volume (absorption calculation necessary) . Lets it sit for 10 or 15 and then does the first run off. Next he sparges with 185 degree water with the second volume equal to 50% of the desired final volume.

I'm thinking of trying this for my first batch later this week.

I'm doing a Brown Ale with a 21lb grain bill and am shooting for a 12 gallon boil volume. I have a 14 gallon mash tun.