First corn mash

[dragonfrog]

Making my first corn mash - an (almost) all grain sort of thing.

Day 0

I did a yeast starter with:

1.5 tbsp boiled yeast slurry (dregs from racking a batch of wine)
90 mL sugar wash backset
150 mL water
a pinch of yeast nutrient (the kind that's a mix of DAP and yeast hulls)
3 tbsp dextrose
an 11 g packet of Danstar "Nottingham" dry ale yeast

After about 1.5 hours I mixed up the same thing again minus the yeast, and pitched the first batch of starter into that. That second step got about 2.5 hours before I pitched it into the full batch of mash.

I cooked up, in about 12 L of water (city tap water, filtered through one of those faucet filters):

2.7 kg corn (1.5 kg was flaked corn, and 1.2 kg was polenta-type cornmeal)
250 g whole rye flour
250 g whole wheat flour
6 g (1 tbsp) calcium carbonate (ground eggshells)

Once this was a really thick porridge, I cooled it by adding about:

2.5 L of sugar backset (next time of course I'll use corn backset)

When it was down to 67 C, I mixed in:

800 g crushed 2-row barley malt
3 crushed tablets Beano

It was really cool to see the porridge thin so quickly - I'd made one all-grain beer before, but that barley mash didn't thin nearly this fast or dramatically.

After about 1.5 hours I aerated the mash a bit by pouring back & forth between my fermenter and cook pot a few times. Once it was in the fermenter, I had room to add the rest of the ingredients:

1.1 kg dextrose
2.6 L backset (the last of what I had)
2.5 L water (to get up to 20 L of total liquid)

The wash was pretty close to a good fermenting temperature (Ian Smiley says to make sure the wash is 38 C or under), and I wanted to go to bed, so I tossed in half a tray of icecubes, stirred the mash until they were melted, and pitched the yeast starter.

Adding dextrose seems to be considered a lesser evil in the homebrew scene than white sugar, as it is corn sugar and is supposed to ferment out cleaner, with less off flavours than white sugar. Since this is to be a mostly corn whiskey, adding corn sugar seemed like the "cleanest" cheat.

I measured the starting gravity at 1.072, but that was with all the grain crud floating in it, so I don't know how closely that would reflect the SG of the mash if I had sparged it. When I ran the recipe through qbrew, it estimated the SG at 1.069; that was a nice sanity check.

This mash is about 25% backset, and that not even corn backset. I think I'll use a bit more in future batches, once the backset I have is the real deal - My favourite whiskeys are in the Jim Beam lineup, and I've read that they use in the neighbourhood of 33 - 40% backset.

Day 1

Mash was fizzing away merrily by morning. Took it out to the garage, as the house stays pretty cool even on hot days, and the garage is generally a couple of degrees warmer.

[Kentucky shinner]

let us know how it finishes out.

[dragonfrog]

This is fun!

Day 4

Stripping run today. It was still fermenting a little, but it was time to run it. Final SG measured at 1.024 (qbrew had estimated a final gravity of 1.019, so not too far off).

Drained the beer through a nylon sparge bag in a 20L pail fitted with a spigot. What a mess! The bag kept getting clogged right in front of the spigot and needing to be pulled clear, shaken about, replaced, the sides scraped with a big spoon... How do people do this normally? Perhaps adding a false bottom to the pail would help. In the end I recovered probably 17 or 18 L of very murky beer in the fermenter, and what felt like another 500 mL and maybe 1/4 lb of spent grain on my shirt. It smelled very nice in the garage.

The still took about 2 hours to come to a boil (it's on a fairly anemic electric hotplate) and then ran for about 2.5 hours. At the end the output was down to slowly dripping distillate at about 25% ABV; I might have run it a little longer, but I don't think there was much left to recover.

I ended up with two 40 oz bottles of low wines, the first at 54% and the second about 35%. I took a few samples of the output starting when the first bottle was half full - there's a lot of flavour in there! It's very raw and rough, but it does seem like hiding somewhere in there is the potential for a nice bourbon...


I started the next generation of mash, with about the same proportions of ingredients, but about 1/3 backset, and using a few litres of spent grain slop from the last batch as the yeast starter.

[olddog]

I ended up with two 40 oz bottles of low wines,

there's a lot of flavour in there! It's very raw and rough

I'm guessing that you did not make any cuts,


OD

[dragonfrog]

That's right OD - I didn't even throw out foreshots. That's why I didn't taste the contents of the bottle, just the output of the still, as all the methanol from the whole batch would be in that first half bottle...

I intend to get about 4 beer stripping runs in, then do a spirit run. I think I'll probably use the approach suggested on this site of collecting in small containers and deciding on the cuts after the fact, as I'm too worried I'd mess up the cuts if I was trying to do them on the fly.

[dragonfrog]

I've run the second generation, which gave about the same yield as last time, and did a sugar wash on the spent grains, with backset from the grain mash. But, that second all-grain mash was the last run my extreme ghetto still had in it - so I had to put a stop to things and build a new still, and the sugar wash sat kind of a long time before I could run it. I don't think it was going to vinegar though, at least not much.

Now I've got a 2" Boka with about a 4' packable column height, and a little liebig to cool the output. Cost me a bit more than I anticipated, as I couldn't buy less than 12' of 2" copper pipe. For the corn slop sugar wash I ran it in pot still mode and with the column unpacked. I was a bit nervous that the condenser wouldn't be enough to knock down all the vapours, and I'd get vapour leakage out the open top of the column, but I didn't smell any alcohol - yay! success!

I think I got a fair bit more alcohol and/or sugars out the the spent grains, as there was more alcohol in the output than the sugar I put in should have accounted for - I got a 40 oz bottle at 56% and a 750 ml bottle at 37%, out of only 1.38 kg of sugar added to that wash. The taste seemed pretty good, so I think I'll keep doing those sugar washes on the spent grains.

With the grains I've got on hand I'll be able to do two more of the kinda all-grain batches. With two more sugar washes on those grains, that should be enough for a good spirit run...

[rad14701]

The amount of spirits you collect is dependent on several factors...

First is the %ABV of the wash... You used 1.38kg of sugar, but with how much water...??? And then you'll have some marginal amount of additional %ABV from the grains, even if reused...

You also have to factor in the constantly reducing %ABV of your spirits as you run in pot still mode... It's easier to calculate the expected amount of neutral spirits when running a reflux column but there is a pot still calculator on the parent site as well...

Where and how accurately you make your cuts, as well as the amount of heat and take off rate, also comes into play...

[dragonfrog]

I was just talking about the straight amount of ethanol - 1.18 L (40 oz) * 56% = .66 L; .75 L * 37% = .27 L, so about .83 L of alcohol, which is about .65 kg (.789 g/L, sez wikipedia)

So, using the rule of thumb that sugar goes to 1/2 alcohol, 1/2 CO2 by mass, 1.38 kg sugar should give .69 kg alcohol. If I hadn't gotten some left over sugar or booze from the spent grain, that would meant I stripped the spent wash down to 40 g, or 50 mL, of alcohol. I had about 12 L of water in there, so that would have meant stripping down to like 0.4% in the spent wash.

I quit when my output was around 20% ABV. According to the pot still calculator on the parent site, that would mean the spent wash was close to 2.5% ABV, which would imply I left behind an extra 300 mL of alcohol. Now, I think that calculation is somewhat bogus - my output started at about 70% from a wash somewhere in the neighbourhood of 7%, so I must be getting a bit more than a single plate of distillation.

The amount I left behind then is somewhere between minimum .4% (50 mL) and maximum 2.5% (300 mL). Anything over the minimum would be what was recovered from the first fermentation on those grains.

[Samohon]

Off to a great start with an all grain dragonfrog.

Keep us posted...

[rad14701]

It's tough to get much less than 2 plates, even with a simple pot still unless you run pretty hard... Boiler head space accounts for one plate and the column and/or lyne arm counts for another...

[dragonfrog]

Finally did a spirit run!

In all, I brewed and stripped seven batches of beer - four all-grain batches, and on the last three of those I refermented the trubs with 2.2 kg of corn sugar.

The low wines came out to about 18-20 litres at 40%. On my puny little 1 kW burner, it took me about 8 hours to complete the run, not counting upward of 4 hours heatup time (I shut down the run on the Saturday, went to bed, and started up again on the Sunday). I collected in 450 mL beer bottles, and filled 24 of them by the time I shut the run down with the output at about 22% ABV.

I went with the "non-linear" cuts method outlined in http://homedistiller.org/forum/viewtopi ... 0&start=15" onclick="window.open(this.href);return false;" rel="nofollow

At first, I was really worried because everything seemed to taste so harsh - I was afraid that the hearts were bleeding right into the tails or something, and I would have no heads cut to make. In the end, I started finding the specific off-flavours people describe as heads and tails, and used that as a guide, not whether what I was tasting actually tasted good itself. It was weird though - the low wines were pretty rough, but still had a nice corn-y taste, and hints of a pleasant whiskey waiting to come out. What I was getting ready to call my finished whiskey, ready to age was just rough, rough, rough.

I ended up ended up keeping as my final hearts, bottles 9-15. In the end, the promised alchemy seems to have happened - the hearts cuts mixed together were way smoother than each one on its own.

Based on copious watering, sipping, and spitting, I ended up blending in some of a number of bottles from the tails that had tastes that weren't too bitter and seemed like they might complement the existing mixture. I used about:
2/5 of bottle 17
3/5 of 20
1/5 of 21
1/5 of 23

I didn't go as far into tails on the stripping runs as I might have - I shut them off once the output was below 20%, because I generally was staying up late already just to get to that point - so, I suspect the tail end of my spirit run probably wasn't as tails-y as some folks'. Still, I'm a bit worried I might have come up with a mix that's too heavy on tails. Time will tell, I guess.

Adding one 450 mL bottle of water brought the whole thing to 70% ABV, and just enough to fill a glass gallon jug with some headspace for oack chips. I'm using those barbecue chips made of used whiskey casks for oaking with.

In the end I kept as my aging cut, about 1 gallon (3.8 L) at 70% = 2.6 L of ethanol, - 32 to 36% of what was in the low wines. I understand that's considered fairly normal. Now a question arises - what to do with the other 2/3 of the output, all those heads and tails?

[Kentucky shinner]

Hey man congrats on your success. Save your heads and tails. pour them into a container together if you want. when you get enough to charge your boiler with them watered down to about 40% ABV, run em. I think you will really like what you get from this. This is called a feints run. Im fixing to do one tomorrow myself.
KS