Halfpenny Brewery, Lechlade

Techniques

Crushing the grain

In order to allow hot water to get at the starches in the grains, the grain must be crushed. It should not be powdered into a flour, however, as this can lead to a big sticky mess that one cannot get any liquid back out of. Ideally then, each grain should be crushed into two or three pieces, hopefully without ripping up the husk too much, as doing so will allow too much tannin to get into the liquid.

Medieval brewers crushed their grain using the same kind of stone mill as used to make flour (sometimes water powered, sometimes a hand-mill, or quern). I cannot believe that these brewers allowed the mill to grind the grain all the way to flour - rather they would adjust the grinding plates further apart in order to crush rather than powder the grain.

My hand-mill is a purpose-built home-brewing device that uses a knurled steel roller to crush grain against a flat plate. I recently had the opportunity to use a friend's bread flour mill - which uses stone grinding plates - to crush grain for homebrewing (I forgot to bring mine). We discovered that when we adjusted the grinding plates to be much further apart than usual, this mill produced results similar to my homebrewing; giving a bit more flour, but not much.

About mashing

Mashing is the process of converting the starches in the grains into fermentable sugars, using the enzymes that are in the malted grain. After being crushed (lightly ground), the grain is mixed with hot water (so that the mixture ends up somewhere in the 145 - 158 F range), and held in this temperature range for an hour or three. During this time, the enzymes will convert almost all of the starches into simple sugars that the yeast can digest.

A starch molecule is made of a long chain of simple sugars all linked together. There are two enzymes that work together to break this long chain down into small pieces. Alpha-amylase cuts long starch chains into smaller pieces, still too large to be digestible to yeast. Beta-amylase cuts very small pieces, simple sugars suitable to yeast, off the ends of the starch chains. So the two working together do a very good job of breaking down the long starches into sugars. Beta-amylase is most active at somewhat higher temperatures than Alpha, but there is a fair overlap in their useful temperature ranges [Noonan Lager, pp. 88-89]. The most important thing about all this to the brewer is that the higher the temperature mash, the sweeter the resulting beer will be.

Infusion mashing

The infusion technique was the predominate method used by the English. This is a very simple technique: grains are crushed into few pieces (each) to expose the partially modified starch kernels. Then these are mixed with hot water to the consistency of medium-thick porridge at approximately between 148 and 156 degrees F. Then this is allowed to sit for between one and three hours. During this time, enzymes in the grain convert the starch into sugars. Finally, the liquid would be drained away from the grain solids.

Using an insulated vessel for the mash

Digbie writes, in "Scotch Ale from my Lady Holmbey":

Heat Spring-water; it must not boil, but be ready to boil, which you will know by leaping up in bubbles. Then pour it to the Malt; but by little and little, stirring them strongly together all the while they are mingling. When all the water is in, it must be so proportioned that it be very thick. Then cover the vessel well with a thick Mat made on purpose with a hole for the stick, and that with Coverlets and Blankets to keep in all the heat. After three or four hours, let it run out by the stick (putting new heated water upon the Malt, if you please, for small Ale or Beer) into a Hogshead with the head out. ...

I should also point out that the normal batch size was quite, quite large by modern homebrewing standards (though small compared to modern commercial practice). Water has a large thermal mass, which is to say that it holds heat pretty well. It is also not the best conductor of heat, so if one has, say, a Hogshead (approximately 64 gallons) of hot water, in an approximately cubic barrel, it can take a long time for it to cool down. Digbie, slightly later in the same recipe writes:

Then put it again into the Caldron, and boil it an hour or an hour and a half. Then put it into a Woodden-vessel to cool, which will require near forty hours for a hogshead.

In order to grow yeast successfully, Digbie's batch needs to cool to at least body temperature. So his sixty-some gallons of wort are cooling 114 degrees F. in 40 hours, or losing 2.85 degrees per hour.

So when scaling these recipes down to smaller sizes, it is quite reasonable to mash in an insulated vessel. Not only because Digbie instructs us to in his 17th. C. recipe, but also because the thermal mass and poor thermal conductance of the large amount of water in the original proportions tend to insulate the interior portion of the mash, and this can be effectively simulated by using an insulated vessel.

Successful infusion mashing without a thermometer

Of course, neither the thermometer nor hydrometer were invented by 1600. So I had to find a way to get the mash temperature right without resorting to the the modern technique of directly measuring it.

Digbie tells us that "When all the water is in, it must be so proportioned that it be very thick." In addition, William Harrison, in describing how his wife makes beer, writes:

... The first liquor which is full eightie gallons according to the proportion of our furnace, she maketh boiling hot, and then powreth it softlie into the malt, where it resteth (but without stirring) untill hir second liquor be almost ready to boile. ...
[Misc-4]

I tried this on a very small test batch of two pounds of grain, in a small insulated cooler, with boiling water. At the time I found that adding 3 cups of boiling water made the grain both a bit too cool, at around 145 degrees F., and too dry, with some grain still dry. 4 cups, however, left the grain just a tad too high, at 160, and was very thick.

Later, Eric Rhude reported on the medieval brewer's mailing list that just ladling the water in a bit at a time worked fine for him [Rhude].

So for these batches, I tried pouring in the boiling water over a height of some two feet, a quart at a time, for a total of 6 quarts worth (including about 1 1/2 quart to cover the false bottom described below). And then in order to let the enzymes have some chance at being too cool in some places, and too hot in others, I didn't stir it up until half an hour after initially starting the mash. And then I let it sit a good long time to let the enzymes do their work.

I'm delighted to report that this worked great. Though I do not have a thermometer, I do have my fingers. After stirring up the batch, it was sufficiently hot that I could stand to dip my finger-tips into it for only a second or so. In a completely different context and use, Norm Thagard and Nelson Pass reported that an object that is 50 deg. C is very hot, and 55 deg. C. is untouchable [Thagard]. I have found that my fingers will put up with a bit more heat, so that 65 deg. C, or 149 deg. F, is almost too hot to touch.

Aside from burning my fingers, the runnings from the malt were sweet and sticky, and after removing the liquid, the grain had visibly lost some starch.

To simulate the mash tun described in Digbie (above), I used a 10-gallon Rubbermaid-brand water cooler to mash in, with a Phil's Phalse Bottom(tm), a false bottom. This is a slightly downward-dished piece of plastic with a huge number of small holes in it, and an elbow that directs a siphon tube into the space trapped between the false bottom and the actual bottom of the cooler. This has the effect of holding the grain away from the inlet to the siphon tube, and allows liquid to be easily removed. This is essentially like a permanently installed colander.

No Recirculation

In modern brewing, it is customary to recirculate the first bit of liquid in order to make a filter bed out of the grain close to the false bottom, so that the liquid that is drawn off is fairly clear. There is, however, no evidence of this practice in any period references that I am aware of. In the absence of evidence, I chose not to recirculate any of the wort in making these batches.

No Sparging

Sparging is the technique of adding additional hot water to a draining bed of grain in order to rinse more sugar out the grain. It is commonly done in modern brewing, but there is ample evidence that this is a post-period innovation. The Oxford English Dictionary lists the first use of the term sparge, when referring to brewing, at 1839, and then again at 1885 [OED, v. 16, p. 117]. Further evidence of the importance of this innovation can be found in Noonan's book Scotch Ale. Noonan quotes W. H. Roberts, a Scottish brewer, writing in 1847:

The process of sparging is, in my opinion, decidedly preferable to a second mash for ale worts, and has ever been considered in this light by the whole of Scottish brewers.
[Noonan Scotch Ale, pp. 90]

I can attest from experience that sparging is definitely an innovation, allowing a much greater extraction rate from the grain. All evidence that I have seen, however, indicates that it is a much more modern innovation, and not appropriate to even Elizabethan-era recreation. As discussed above, however, not using this technique has a profound effect on the quantities of grain required to produce a given strength of ale or beer. By using modern temperature control on the mash and sparging, I need less than half the amount of grain that is required by the older techniques. But then I also get a more modern-tasting result.

So I didn't sparge; I simply drained out the liquid that was in my mash.

A second running

The general mashing technique used by English brewers in the Elizabethan period was double (or triple) infusion mashing. In this, after the first infusion as been done (as described above) and the liquor has been drained off, a second batch of hot water is added to the grains, which are again allowed to steep. The second batch of liquor is then drained off and fermented. For very potent beers or ales, a third running would be performed in the same way.

These second and third mashings are mostly useless for enzyme activity - the enzymes have mostly quit by the time the first mashing is over. But not all of the sugars will be collected in the first running. These second mashings serve to rinse more sugar out of the grain, giving weaker beers or ales for the effort. This helps improve the over-all efficiency, but not as much as sparging. Adding together the combined amount of sugar I got out of the grains from both runnings of the second batch, I still only got about two-thirds of the efficiency that I would have using modern techniques. This is an important point to keep in mind even for recreations of late-period beers: The efficiency of the process is lower; the efficiency of an individual running is much lower.

I have no justification for using a double-infusion technique on a pre-Elizabethan ale, other than that doing so does not change the results of the first running one bit, and there is still a substantial amount of sugar still trapped in the grains after running off the first batch; it would be a same to waste this by throwing it out. So for the second recipe, I did a second infusion as well, and made an ordinary ale out of this.

No Post-mash Boil

This is the important difference between medieval English ale brewing technique, and both beer brewing and Elizabethan ale brewing: medieval English ale was not boiled after the wort was strained from the grains.

Judith Bennett reports that many people brewed ale for sale, at least in more rural communities:

Commercial brewing was very widespread, especially in the countryside. In Brigstock before the plague, more than 300 women -- about one-third of the women who lived on the manor -- brewed ale for sale. In Alrewas (Staffordshire) during the 1330s and 1340s, between 52 and 76 brewers sold ale each year (in a village with about 120 households). In Wakefield (Yorkshire) between 1348 and 1350, 185 women -- accounting for almost one-third of all women -- brewed for sale. ...
[Bennett, pp. 18--19]

She also writes that getting the ale to market before it spoiled was a very great and continuing concern [Bennett, pp. 45 & 85].

Bennett suggests that the longevity of beer, especially in comparison to that of ale, is due to the addition of hops. Hops clearly help -- the alpha acids in hops that give beer its bitterness also have a preservative effect [Smith pp. 24--25].

However, I do not believe that is the complete story. It is worth noting that Digbie, in "Scotch Ale from my Lady Holmbey", concludes:

It will be fit to broach after a year; and be very clear and sweet and pleasant, and will continue a year longer drawing; and the last glass full be as pure and as quick as the first.

Note that this is indeed an ale recipe -- no hops were added. Also, he is not making the ale at a much greater strength than the earlier ale we are interested in (at least, not the stronger ones). Yet Digbie's ale lasts between one and two years, and is described as clear. I can also attest to the clarity of ale that is made according to Digbie's methods. After making the Debatable Brewer's Ale for Fish, we found that the ale was clear, and that it has lasted well for at least six months. Now clearly some of this is due to modern sanitation, but Digbie did not have the benefit of antibacterial agents such as Iodophor(tm) or even Bleach, and yet was able to make ale that lasted a year or two.

Further evidence of this difference can be found in Smith's book on the history of Beer:

... Overall it was a thickish liquid, low in alcohol from the incomplete ferment. One person from the 1200s described it as "for muddy, foddy, fulsome, puddle, stinking; for all of these ale is the only drinking." It was also well described in rhyme about a notorious Cornish ale cited by Andrew Boorde in 1540.

Ich am a Cornishman, ale I can brew
It will make one cacke, also to spew.
It is thick and smokey and also it is thin
It is like wash as pigs had wrestled there in

[Smith, p. 24]

Clearly this was cloudy stuff. Also, ale spoilage was a real concern at the time.

I suggest that besides the hops, one particular aspect of adding the hops significantly increases the keeping time of beer or ale: the post-mash boil.

In brewing a beer, after the wort has been run off the grain, it is put in a big pot and boiled some more and hops are added. The heat of the boil is necessary to dissolve the hop alpha acids into solution effectively. But the other thing that happens early in the boil is that many of the proteins are cooked (and later fall out of solution). When this process of cooking the proteins culminates, the wort will foam up aggressively, and the brewer must be careful not to let the wort boil out of the pot, all over, and make a big mess.

I submit that if the post-mash boil is not done, then these proteins will stay in solution in the ale, and give extra nourishment not only to the drinker, but also to some types of bacteria that might like to infect the drink. Since medieval ale apparently spoiled easily, it probably wasn't boiled the second time after the mash.

That the ale wort was not boiled is stated by Bennett, who then adds into the cost of brewing beer an increase for the cost of fuel [Bennett, pp. 86--87].

This argument against a post-mash boil is, however, speculative. Part of the point of brewing these batches was to see if the now customary second boil was necessary, or if good ale could be produced without this step. So far, the results seem to back the historical evidence: the first batch was quite cloudy and tasted very much like liquid bread on the third day after being made. Despite this, it was quite drinkable and refreshing. Despite modern care with sanitation, it started to sour on the fourth day, and was fully sour before it started to really clear. (It ended up about as sour as Rodenbach Red Ale; not as sour as Rodenbach Grand Cru, and not even close to as sour as Cantillon Gueuze.)

Cooling

Digbie describes slow-cooling (in a large vat, for some 40 hours). Markham describes a quicker cooling technique involving pouring the hot wort into a shallow open vat. The problem with the open vat method is that in exposing the wort to a lot of air, one is almost sure to inoculate the wort with who-knows-what type of undesirable organisms [De Keersmaecker]. This works great for some Belgians, who deliberately inoculate their beer, lambic, with whatever happens to be floating by in the air that day. Unfortunately, I live in the wrong micro-climate to try such things. So I opted to let the wort cool by just sitting, closed, over night.

Fermenting

After the wort is cool, a modern home-brewer would pitch in the yeast, make sure the wort is well aerated, and put on a blow-off tube or fermentation lock. Digbie and Markham suggest some sort of blow-off technique.

On the other hand, many professional brewers, using equipment that is now considered antiquated, ferment in large open vats.

For these batches, I opted for sort of a compromise, and used 3- or 4-gallon plastic fermenters, either with a lid that does not quite seal or with a plastic bubble-lock. I kept them closed to prevent possible infection, though that doesn't seem to matter with the addition of the Lambic dregs.

Implications for recreational brewers

To the modern brewer, the quantities of grain described in these sources seem extraordinarily large. However, the process is so inefficient that large quantities of grain are required to produce ale of adequate strength using these older techniques. The upshot of this is two-fold. First, if one is trying to recreate an all-grain beer or ale, one should plan on using a lot of grain. Second, if one is attempting to adapt an (Elizabethan) English beer recipe to the use of modern malt extract, one should keep firmly in mind the low efficiency of the boiling water infusion mash technique. So whereas a modern extract brewer would use 2/3 of the malt extract (by weight) as in a modern all-grain recipe, they should use approximately 3/8 as much extract as grain in the original recipe. (They should also keep in mind that virtually all period recipes measure the grain by dry volume rather than by weight, and convert appropriately.)

I hasten to caution that an extract-based recreation of a late-period English beer won't be as accurate as an all-grain recreation using appropriately period mashing techniques. The mash used is much thicker and hotter than used in commercial brewing (and thus malt extract production). As a result, the beer will have a much different character: the period all-grain beer will be sweeter and have much more "body" due to the high temperature of the mash. Still, the recreation of such a beer won't be bad, merely not as good as it could be.

On the other hand, I do not think that one can properly recreate a medieval ale using modern malt extract. Unlike the mash process used in this recipe, the extract will have been boiled as part of the manufacturing process. This boiling will cook out many proteins that are suspended in the wort, and as a result greatly change the character of the ale. So while an extract-based ale will be ale in the sense that it contains no hops, it wouldn't be particularly medieval in character.