Jump to content

Recipes for sweet mash and sour mash

This topic has been inactive for at least 365 days, and is now closed. Please feel free to start a new thread on the subject! 

Recommended Posts


M'Harry's remark about letting the solids filter to the bottom does not really imply unfiltered distillation so much as a filtration that was not efficient and still let a lot of solid matter in the still. It could be a filtering as crude as simply taking a bucket to fill the still leaving most of the solids behind. I am still curious about the "Mash Filter" Taylor bought for the rebuilding of the OFC distillery in 1870.

Mike Veach

Link to post
Share on other sites

Could be Mike, although he is constantly warning against the risk of the "grain" burning and singieng in the still. Mash is quite thick so maybe he did a kind of rough filtration although he does not mention it.

I will quote later the part where I think he is referring to a sour mash system, which he only mentions once. His main concern in the book is mashing and in most of the discussions under specifc heads like half corn and half rye, he refers only to "water" being added both to scald (hydrolize) and to cool off. Also, his remarks indicate that sour mash is a kind of innovation, it is not the regular way, is the tenor of the remarks. Maybe this passage is evidence that it was slowly entering distilling. I can't tell though what his backset mixture is, it seems to be a mixture of slop, water and yeast only but maybe I am not reading it right. Anyway more to come.


Link to post
Share on other sites
On the point of slops being a starter, certainly a ferment will kill most yeast as will a boil. However there is residual fermentable sugar in any beer, slops or backset and there would have been more in the old days when fermentation and distillation were less efficient than today.

I infer that wild yeasts started to work on that sugar immediately (as Roger explained too) and that the acid environment of the slops favoured the "good" wild yeasts.

This is a fascinating subject and one that is near and dear. I wish I had time to research this myself in M'Harry (as well as Byrn's Complete Practical Distiller, which was published in 1875 and so after sour mash was established). I happily have both of these in the high quality reprints from Glenn Raudins, which I again highly recommend, as I know Gary does.

Anyway, a few comments. Distillation temperatures will absolutely kill dead any yeast, but fermentation, even at higher alcohol such as 8% (typical of modern distiller's beer, will not. I have often reused yeast from fermentations; although it is better not to use yeast from high alcohol batches, it will work.

So, if slops are unheated fermentation solids strained out from undistilled ferments, they should have lots of viable yeast.

As I think I have posted before, the reason that sour mash is important in Kentucky but not in Scotland is that Kentucky's famous limestone water is alkaline, and it needs the balancing acidity of sour mash to achieve the proper mash pH of 5.3-5.6. Scotland's waters are typically soft and with low alkalinity, so a sweet mash will settle down into the proper mash pH without any additional acid. (The mash pH is important for the activity of the amylase enzymes which convert the starches to fermentable sugars.)

I seem to remember reading in some historic distilling source that wicker baskets were pushed down into the fermented mash and the more or less clear beer was bailed out into the still. I can imagine that the remaining solids were considered the slop. This would certainly turn sour with any time at all, especially if they were resued serially.

I have made a mash of malted barley, corn and rye and allowed it to ferment spontaneously. It smelled pretty funky, but it fermented, and I can imagine this being a useful fermentation. And certainly low pH (high acidity) will kill off many bacteria while leaving yeasts OK. This is the basis of what brewers call an "acid wash," in which they wash their brewers' yeast with (typically) phosphoric acid to kill spoilage bacteria.


Link to post
Share on other sites

Jeff, thanks.

Here is part of M'Harry from chapter VII on "To Make Four Gallons From The Bushel":

"Mash your grains in the method that you find will yield you most whiskey - the day before you intend mashing, have a clean hogshead set in a convenient part of the distillery; when your singling still is run off, take the head off and fill her up with clean water, let her stand half an hour, to let the thick part settle to the bottom, which it will do when settled, dip out with a gallon or pail, and fill the clean hogshead half-full, let the hogshead stand until it cools a little, so that when you fill it up with cool water, it will be about milk-warm, then yeast it off with the yeast for making 4 gallons to the bushel, then cover it close, and let it work or ferment until the day following, when you are going to cool off; when the cold water is running into your hogshead of mashed stuff, take the one-third of this hogshead to every hogshead (the above being calculated for three hogsheads) to be mashed every day, stirring the hogsheads well before you yeast them off. This process is simple, and I flatter myself will be found worthy of the trouble".

Comments, Jeff or others?


Link to post
Share on other sites

Based on seeing the restored GW distillery in Mt. Vernon and reading these accounts, it seems apparent that pots were both solid (no drain) and fixed (e.g., buried in sand) and that anything which needed to be done inside the pot was done by removing the head. Although this seems like it would be very labor intensive, labor probably was more plentiful than just about anything else.

Presumably one of the reasons a "commercial" distillery like Washington's had 5 stills was because of the cool-down and clean-out cycle that inevitably followed each distillation, particularly the beer run.

A solid copper pot would eventually wear out, the sand would break through, and the whole thing would be torn out and replaced.

Sorry, I know you guys are wrestling with the sour mash question, but it got me thinking about this other stuff.

The same accounts that credit Crow with the introduction of sour mash also credit him with introducing (though not, just to be clear, inventing) the sachrometer and introducing hygene practices, such as thoroughly cleaning the mash tubs and fermenters between batches. It is also claimed that he was the first to sell only aged whiskey. Whether or not all of these individual claims are true, it is perhaps true that he was the first to apply all of these practices systematically.

The result, the accounts tell us, was that his product was consistent and consistently good, so much so that discerning drinkers asked for it by name.

While it's possible that not all of the above is true, it seems equally unlikely that all of it is false.

Link to post
Share on other sites


Thanks so much for posting these recipes. Absolutely fascinating!

Other enthusiasts:

There's a lot to ponder here. A few quick things I notice right off the bat:

The first recipe has the option of not using slop or backset of any kind, and seems to me very much like it might be derived from a beer (i.e. lager, ale, etc.) recipe. It seems like it would taste "sweet" during the mashing.

What is slop??? My guess is this: slop is what you feed the pigs. I'll have to look around for a recipe for pig slop... it's possible that the remains of a distillation run might not be nutritionally sufficient, so there might be added grains... thus the slop might be capable of supporting living yeast. Or maybe no added grains, but the original fermentation didn't use all the starches/sugars, and so as the slop sits around for a few days it continues to ferment. According the the second recipe, slop can be "very hot". Hmmm. Harder and harder to figure.

The use of wheat OR rye as an adjuct grain: how curious! This leads me to all kinds of elaborate theories.

The second recipe: the mash would certainly taste sour! Why do you wait so long with the corn meal? I guess you're letting the starches dissolve. In this recipe: rye is the only option, not wheat. Whew! At least that lets me keep the Tim Dellinger Theory of Rye as an Adjuct Grain intact.

My feeling is that the second recipe is very much a sourdough-style recipe, with yeast and bacteria fighting it out and reaching equilibrium and doing all kinds of interesting things. The first recipe you pray that bacteria never take hold; in the second you acknowledge and leverage the presence of the bacteria.

It's possible that today's sour mash process bears more resemblance to the first recipe than the second.

Tim Dellinger

Link to post
Share on other sites
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.