Mash thickness

[Gillman]

Good article by Chuck Cowdery in the current Malt Advocate on the nature of continuous distillation and its role specifically in the manufacture of bourbon. A representative of Vendome (the renowned still manufacturer in Louisville) is quoted that in the last 45 years, the amount of water in mashes has fallen by approximately half (from 44 gallons per bushel originally to mid-20's currently).

This is done to economise on energy costs (it costs less evidently to heat less water).

It seems a still can vaporise the thicker mashes just as well, or maybe the extra cost to do so efficiently is much less than to process a mash holding 44 gallons per bushel.

I find this interesting and I wonder if the taste of new spirit is different when made in the newer way.

Gary

[MGades]

I hesitate to comment because I haven't read the article (is it the Third Quarter 2007?), but what is the relationship between the concentration of the mash and the content of the beer? (Isn't it the Beer and not the Mash that is introduced into the still?)

Since distiller's beer is now about 10% ABV, does this mean that the beer used to be about 5% ABV 45 years ago when there was 2x as much water in the mash?

[cowdery]

I can't comment on Gary's taste question, I don't know. Contrary to the PR departments that like to portray the distilleries as never-changing, they are in fact always trying to "tweak" the process. My assumption is that they reduced the ratio of water to grain gradually and didn't find a negative affect on taste.

I can perhaps clarify a little bit for MGades. With American whiskey, the mash goes into the fermenters and ultimately into the still intact, i. e., containing grain solids, so the mash is the beer. Nothing changes except the addition of yeast and the conversion of sugar into alcohol, but the water:solids ratio does not change. I guess it makes sense, logically, that a thicker beer would have a higher ABV.

Remember, the whole object of the exercise is to concentrate the amount of alcohol by eliminating water. If you can eliminate some of the water by never introducing it in the first place, that's efficient. The main energy "cost" in the operation of a distillery is in boiling water, so less water to boil, less cost.

Yes, it's in the Third Quarter 2007 issue. Cover headline is "Judged by the Cover."

[jeff]

Not completely related to whiskey, but here is some information on mash thickness as it relates to beer:

The grist/water ratio is another factor influencing the performance of the mash. A thinner mash of >2 quarts of water per pound of grain dilutes the relative concentration of the enzymes, slowing the conversion, but ultimately leads to a more fermentable mash because the enzymes are not inhibited by a high concentration of sugars. A stiff mash of <1.25 quarts of water per pound is better for protein breakdown, and results in a faster overall starch conversion, but the resultant sugars are less fermentable and will result in a sweeter, maltier beer. A thicker mash is more gentle to the enzymes because of the lower heat capacity of grain compared to water. A thick mash is better for multi-rest mashes because the enzymes are not denatured as quickly by a rise in temperature.

That is taken from John Palmer's How to Brew, an excellent resource for home brewers. If the above is at all applicable to whiskey "beer", then it would seem counterintuitive for the distillers to mash thicker, as a thinner mash would produce greater yields.

[Gillman]

Good point, Jeff.

Could special enzymes be added to a thick bourbon mash which would resist the inhibitory quality noted by Palmer? Home brewers (at any rate) wouldn't do this, but commercial brewers, and distillers, do so on occasion I understand.

Could the new makes (and therefore the aged ones) made by either process taste the same? Seems unlikely, but how they might differ I cannot say...

Gary

[barturtle]

Not completely related to whiskey, but here is some information on mash thickness as it relates to beer:



That is taken from John Palmer's How to Brew, an excellent resource for home brewers. If the above is at all applicable to whiskey "beer", then it would seem counterintuitive for the distillers to mash thicker, as a thinner mash would produce greater yields.

This is my first thought, too. As using less water would mean that the starches would reach stasis (the same amount in the water as in the grain) at a level that would leave more in the grain that would never get fermented, this is wasteful.

This lossy stasis level would also present itself in the oils and such that are extracted during the mashing process.

The question is then how much difference in total starch/oils/other good stuff is lost...Some quick thoughts (without any evidence to back them up) tells me that to take the remaining fermentable/other materials from say 4% to 2% would require twice the water...at some point this doubling of water(an exponential curve) has to hit a point of diminshing returns...where the point at which the losses in the beer start to show up in the minimal amounts of flavoring agents that make it through the still, I can't say...but I'm betting one of the labs at the distilleries has a good idea.

[cowdery]

Some distillers do use synthesized enzymes but Jack Daniel's, for one, makes a thick mash and does not use enzymes.

Wouldn't the fact that American whiskey mashes are cooked affect the statis level and allow the starch to be almost completely dissolved, regardless of the water content? Wouldn't this fact also make the comparison to beer mashes irrelevant?

[barturtle]

Wouldn't the fact that American whiskey mashes are cooked affect the statis level and allow the starch to be almost completely dissolved, regardless of the water content? Wouldn't this fact also make the comparison to beer mashes irrelevant?

I see where you are coming from with this...imagine cooking pasta with very little water...the water won't be able to take away enough starch and will thicken into a nasty mess...a little more water and while you might not have a mess in the pot, the pasta itself will still be starchy and stick together...a lot more water and you have well cooked, non-sticky pasta.

In this illustration the middle condition is the problem I think could be ran into; the water and the pasta has reached the point where both contain the same amount of starch...lets call this 20% starch...if it took 1 gallon to dissolve that much starch out of the pasta(and at this point the pasta has 20% starch too), then it would take 2 gallons to take it to 10%...4 to 5%, 8 to 2.5%...change this formula to thousands of gallons for the volumes used in a distillery and you start to see an issue in how much water you can use and how much it takes to reclaim the hidden percentages in the grain.

The starch would only be dissolved to the point at which both the grain and the water have the same amounts in them...IIRC water weighs 8lbs/gal Jeff's thinner mash of 2 quarts per pound of grain means that it's a weight ratio of 1/4 grain/water...halve the water and you might not have enough to dissolve enough starch out and would then be wasting lots of fermentable material....but you'd have a great glue for doing paper mache.

Of course, I could be completely wrong about all of this...well, not the using plenty of water to make pasta part...but maybe the mashing stuff...

[Gillman]

Cooking just solubilises the starches, so I am not sure the analogy with beer mashes isn't a suitable one. In the end, you still have a given amount of starchy material to convert just as with a full barley malt mash, the only difference with distillers' mashes is they contain some unmalted materials (some brewers' mashes do, too, e.g. for Guinness).

I would think enough water is added even to a thick mash to ensure all the sugars are converted from the starch and run into solution. Probably in other words we are speaking relatively and the alcohol yield is the same in both cases, just more dilute with a thin mash.

Gary

[barturtle]

I would think enough water is added even to a thick mash to ensure all the sugars are converted from the starch and run into solution. Probably in other words we are speaking relatively and the alcohol yield is the same in both cases, just more dilute with a thin mash.

Gary

Ah, and that reminds me of one more thing...even if you are using enough water to capture the starch from the grain, are you using enough water to let the yeast eat it all before the alcohol reaches the point where it kills off the yeast?