Blown malt (old style brown): making it at home

[Fuggledog]

Hi,

I've been spending quite a bit of time reading through Ron Pattinson's blog about the history of porter and stout, and of course G.W's research and theories on this topic. For quite a while I've really wanted to try making an 'authentic' porter (if such a thing exists), and given the changes in the nature of porter over the centuries I decided to make several different versions guided by historical recipes from Ron's site (with Kristen English's experimentation), The Durden Park circle published recipes, and Randy Mosher's excellent book 'Radical Brewing'. One point I keep getting stuck on however is what 'brown malt' was actually like to use as a brewing material, and how it could be replicated. It seems without this key ingredient, my attempts to make a 'true(ish)' porter (at least one from the 18th century) would be in vain. There seem to have been two types of historical brown malt. The first is the diastatic kind that could be used as 100% of the grist, was kilned over a hardwood or straw fire and that was sometimes called 'blown', 'snapped', 'high-dried' and porter malt. The second may also share some of these names, but possibly emerged in the 19th century when porter grists included pale malt along with brown and (after 1817?) black patent malt. I get the impression (can you tell I've done no real research on this topic myself - but rather an internet browse of other people's findings), that the second form of brown malt is more akin to the modern stuff.

Anyway, to cut a long story short I decided to have a go at making the old brown, diastatic, 'blown' malt at home. I thought maybe some other nutcases out there might be interested in the process and results of this experiment, so took a short video and some pictures as i went.

I used a firepit from B&Q, and a large metal vegatable strainer from Tesco's to hold the malt. I'd read from an engineering book I found on google books (written in the 19th century and describing malting processes), that blown malt was sometimes made on a mesh screen over a hard wood fire. The malt should be dry and in a state like pale ale malt (so i just used pale ale malt from the malt miller to start). There has been some discussion about the type of fuel for the fire. One author (G.W.?) suggested that to be authentic it really should be a hornbeam fire, so i ordered some hornbeam 'shorts' (after a bit of hunting online) from the 'Druid's wood' supplier. it was very expensive, but I'm glad i tried it. next time i'd just use oak, beech, or even dry sycamore (i have a lot of the latter lying around). The key point is to have a very hot fire, that generates as little smoke as possible (although to be honest the smoke aspect became irrelvant). a short blast of high intensity direct heat is the key. The malt should 'snap' or pop like pop-corn for it to be called blown malt. this process indicates that you aren't 'baking' the malt, but rather giving it a good 'fry' like a raw steak on a hot pan. The outer layer of the malt seperates from the inside as air between the two expands. Anyway a second key point is that this brief exposure to a very hot fire should keep the enzymes 'intact' within the kernal whilst the outer layer colours and develops toasty, roasty flavours. So to summarise i was looking to produce three effects: 'snapping'/popping malt over a hornbeam fire; a brown appearance to the malt; a malt that had enough diastatic potential that it could be used 100% of the grist.

Following I made sure the fire was burning well in the fire pit with the basket heating nicely, then poured the first batch of pale ale malt into the basket, making sure it was laying no thicker than 1/2-1 inch (this bit was from one of the old malting books re. blown malt). Then i watched and waited. If I had the fire buring properly, the malt soon began to pop, almost straight away. It was loud, unmistakable and quite exciting for a geek like me. This was accompanied by the unmistakeble aroma of 'popcorn' although with a more malty edge. Using a fish slice as a 'shovel' I turned the malt once it started to smoke. There was only a small window in which to turn the malt before it started to burn, smoke heavily then set alight. I could see from this experience why the maltsters found it so differcult to get insurance if they wanted to make blown malt. I really had to watch it like a hawk, then turn it like mad. The colour quickly developed. I found that some bits inevitably stuck, or burn't slightly, greating a bit of a mix of colour in the mass of malt (i.e. brown with some black/chocolate flecks). There was also some carbonisation of some of the malt, and a slight stickiness in places which seemed to tie in with historical accounts of the 'essences' of the malt coming out due to the heat. Once I'd completed one small batch I tipped it into a large bin, and began the process again untill I'd 'snapped' 9kg of malt. Once cool i bagged it to mellow. The house smelt strongly of toasted malted bread. There was no smokiness to the malt, despite the fumes from the fire going straight up into the malt bed. However my setup was very inefficient and not like a kiln (i had no 'walls' or sides to funnel the heat - and smoke - through the malt). I also tried to see how far I could push this technique to colour the malt, but there seemed to be natural barriers in the sense that the malt would go past a certain point then very quickly start to burn. I made the 'blown' malt as dark as I could do without burning it. It might be hard to see from the pics (below) but it is much darker than modern amber malt, but not as dark as modern brown.

Unfortunately I don't have an Iodine to test the diastatic capacity of the malt, so I may have just spent a lot of time trashing some pale ale malt to make a wierd 'amber/brown' snapped malt. However i did crush a handful of the malt and mixed it with approximately 1L of 66C water in a thermos. It seemed to take a while (2 hours), but despite it being a very dilute mash (like drinking the last runnings on sparging), the wort was sweet after that period, tasting like watered down Horlicks, so i am very hopeful that some enzymes have survived (although i may need to do quite a long mash if i use this malt 100% of the grist). the flavour from this very preliminary test, was of a biscuity, toasty, malt accented wort with a roasty aspect that blended well. If i was mixing modern malts (although I don't know lot about the flavours of various malts), I'd guess something like a mix of munich, modern amber, modern brown and perhaps a touch of chocolate or black patent malt. As expected, there certainly wasn't any of the caramelly sweetness you'd get from crystal malts, but the 'malt profile' was very prominent. Is that something you'd get from one of the special Belgian malts like melanodin?

I'd really welcome anyone's thoughts on this report, and I'll certainly report back once I have some iodine and have actually started brewing with this malt. If the enzymes are there however, I'll be pleased as it does seem to have a lot of the qualities attributed to the old blown malt.

some pics below:

The hornbeam (later had to add a lot of sycamore)



The setup:



Pale ale malt ready in basket:



close up of malt during snapping:



Just about finished:



Blown malt cooling:



Detail of colour. Note that this looks very similar to its original colour in this picture. 'In the flesh' there is quite a clear difference in colour:



The final batch which i pushed as far as possible (actually set it alight), then rescued:



Next time I'm going to try making it in a 'kiln' with a upturned galvinised bin with the bottom cut off to form a 'chimney' which should help to funnel the heat. Will be interesting to see if this makes the malt smoky too (at the moment I can't detect any 'woodyness' or 'smokiness' although that might come out once the malt has had time to rest. the aroma has changed quite a lot already in 24 hours from 'toasted malty bread' to a much more complex aroma: sort of like a coffee, toasted pop-corn, malt smell. Sorry that probably isn't very helpful. completely different to the other malts I've sniffed! (i.e. choc, brown, amber, patent). I keep wondering if there are some belgian malts that have some of these characteristics?

cheers,

Ben

[Tom_D]

Excellent work sir! Having read the durden park book, I've often wondered about the original brown malt, it is a real curiosity. Keep us updated, I'm intrigued about how this will turn out.

[gregorach]

Fascinating... Do keep us apprised of how it turns out. Maybe even one to write up for Brewer's Contact.

Of course, to really do the job properly you'd need to source an 18th variety of barley and grow it without modern fertilisers to get the right nitrogen / amino acid content.

[Graham]

Here is something that I made earlier - sorry about the length of it

Old-time malt
Old-time malts, being those in use prior to about the early Victorian period, were quite different from modern malts. Old-time malts came in pale, amber and brown varieties, which are familiar names to modern brewers, but they are similar in name only. Their method of manufacture and therefore their characteristics were significantly different from the modern counterparts. These pre-1800 malts were generally dried in a small oven or kiln that had not changed much since Celtic times. Indeed, a medieval-style ‘keyhole’ grain-drying oven or kiln, situated in the aptly-named village of Kilnsey, North Yorkshire, was still in use by a local publican brewer as late as 1845.

These malts were dried over a local fuel, usually a hardwood of some sort, at relatively high temperatures for relatively short periods of time compared to later practice. The difference between pale, amber and brown malts was the kilning temperature and time the malt spent on the kiln. Brown malt was kilned for four to eight hours, amber malt for eight to twelve hours at a lower temperature, and pale malt for twelve to twenty-four hours at an even lower temperature; usually at the shorter end of these time ranges. These were very short times in comparison to modern, or mid-Victorian, pale ‘ale’ malt, which spent about five days on the kiln.

Unlike modern malts, old-time malts were not given much of a gentle drying phase before the ‘finishing’ stage of kilning. The malted grain was finished at a fairly high temperature while the interior of the grain was still moist. This implies that a degree of stewing would have taken place within the grain, which would produce sugars and amino acids similar to mashing, or similar to crystal malt. The moist interior of the grain would activate the diastatic enzymes which would then produce sugars from the starch while the temperature was between 60° and 70°C. Towards the end of the kilning process the temperature was raised to finishing temperature and, after the grain had dried out, the higher temperature would cause the sugars to react with amino acids, a condition known as the Maillard reaction. The Maillard reaction is a flavour-forming and colouring reaction that causes rich, malty flavours to be produced and an enhanced degree of colouring to be imparted. Because unused precursors to the Maillard reaction are present in the finished malt, significant additional darkening can also occur in the copper during the wort boil.

The most popular of the three basic malts was brown malt. It would have been the most flavoursome malt due to the Maillard reaction, but it was also the cheapest. However, its popularity and low cost was probably because, in the days prior to fungicides and insecticides, brown malt had superior keeping qualities during storage. The higher kilning temperature would kill parasitic pests; the lower moisture content, the hardened husks and the deliberate smoking would have helped to keep parasites from re-establishing themselves. Pale malt, on the other hand, probably had to be turned into beer not long after the harvest of the grain.

Brown malt was probably little different to medieval or even Celtic malt, and it survived in a small way until the 1950s. It was deliberately smoked by laying hardwood faggots on the fire towards the end of kilning, which, apart from quickly raising the temperature, smoked profusely. Brown malt, smoked over hornbeam, was favoured for early London porters. Smoking was a typical food preservative process of the day, but the type of fuel used affected the flavour.

Whereas brown malt spent just a few hours on the kiln, less than eight hours, the lighter malts, amber and pale, were kilned for a longer period at a lower temperature. This resulted in lower Maillard reactions therefore producing less colour and flavour than the brown. Amber can be considered to be a mid-way point between pale and brown. Smokiness would still be apparent in the amber, but not to the same degree of smokiness as with the brown.

Smokiness was kept to a minimum for pale malt; indeed, in later years smokiness in pale malt was considered a fault, but the kilning techniques of the time and the fuel usually employed; wood, peat, or turf, ensured that a degree of smokiness was inevitable. Truly smokeless pale malt required a smokeless fuel in the kiln; charcoal, Welch-coal (anthracite), or coke. It takes eight tons of trees to make one ton of charcoal, and demand for charcoal often outstripped supply, so the stuff was very expensive. Suitable anthracite coal was only available from Pembrokeshire at the time, and was shipped from Wales by sea. Coke made from the coal of the northern coalfields could be suitable as long as it was low in sulphur, but the coke-making process was not invented until about 1650, and coke was not produced on an industrial scale until well after Abraham Darby’s blast furnaces appeared in the early 1700s. Even so, the weight of the stuff and the state of the roads made cross-country transportation by cart uneconomical. Again, the stuff was transported around the coast by sea.

Coal and coke was impractically expensive for brewers that were not situated close to a port, a navigable river or a canal, but there was nothing that could be called a national canal network until the 1790s. Even for those brewers situated within economic cartage range of a port or a river, transport costs were high, and the transport chain usually required several transhipments along the way. Between 1667 and 1889, any coal entering a fifteen-mile radius of London was taxed by the city of London even if it was destined to go elsewhere. So any coal that entered the south-east of England via the Thames was even more expensive.

[mysterio]

hardwood faggots

Did anyone else snigger at this, no, just me, never mind.

[Fuggledog]

Many thanks for the feedback and thoughts, I really appreciate it, thanks guys.

Also thank you Mr Wheeler for the detailed response regarding the history and character of these old style malts. I got the sense from your reply that to follow more closely with the old-style snapped malt I'd need to malt some of my own barley so that I could dry it (kiln it?) over the fire for a longer period (say four hours), then increase the heat. I'm guessing that if I made a kiln, rather than an open fire, and had the malt suspended over the fire for this period there might be a more smoky flavour? Certainly I lost a lot of heat (and some smoke) from the 'sides' of the fire. I've also read seeminly conflicting reports about the dampness of the malt prior to it being subjected to 'the flare' of the fire. There was a bloke from somewhere in Scandinavia on the historic brewing forum (http://www.pbm.com/mailman/listinfo/hist-brewing) who steamed his malt prior to the fire to 'rehydrate' it, so I could try that, or perhaps soak it in cold water for an hour prior to the fire? Any thoughts would be welcome. I think the bloke in question reported that his blown malt was like a smoked Belgian special B - so this sounds a bit like the old brown malt you describe above perhaps? I think Mr Pattinson speculated that damp grain would make the enzymes more suceptible to damage via stewing, than if the malt was allowed to dry first before 'frying' but i must confess to being out of my depth re. the biological and chemical processes involved. Perhaps I should try both methods and report back? Making a kiln big enough to dry 8kg or so of malt at a time might be tricky but could be worth the effort to find out what this malt was actually like.

re. the smokiness I found that the hornbeam produced a lot of heat, but not actually much smoke. it was quite a 'clean burning' fuel. then again if the only exit for the smoke is through the malt, and it sits there for 4 hours minimum, I guess it would be more smokey. incidentally, the place where i bought the hornbeam described it as a wood that was traditionally used in smithies due to its intense heat. An intense heat was definately needed to snap the malt as otherwise it just seemed to slowly bake, even when placed directly over the fire.

I have some iodine coming in the post, so will report back on the capacity of the malt to self-convert. if it does I'll consider this 'prototype' blown malt a partial success, but still keen to try new approaches for great authenticity.

thanks again for your thoughts and contributions, much appreciated,

cheers,

ben

[Graham]

Thank you Mr Wheeler for the detailed response

Actually I cut and pasted it from something else that I had written.

My kingdom for a Tardis.

One thing that stands out about old-time brown malt is the very short time that it spent on the kiln, just four hours according to William Ellis in 1736. When one considers that modern malts, or at least modern malts before computer control and dehumidified-air dryers, spent four or five days on the kiln, it brings brown malt into some sort of perspective. There is a hell of a difference between 4 hours and 120 hours.

Malt of the Victorian era was very gradually dried at low heat before the hot finishing stage. It started off at just above ambient temperature and the temperature was raised daily until the grain had dried thoroughly, only then was the temperature raised to kilning or finishing temperature proper for the last two or three hours.

That sort of thing cannot happen in just four hours. It seems that brown malt was thrown onto a relatively hot kiln while the grain was wet. From this I surmise that a certain amount of stewing, or mashing, went on inside the grain, which produced abundant sugars and amino-acids, which then reacted in the Maillard fashion to produce the colour and flavour. This is somewhat similar to crystal malt. I guess that to replicate this you would have to allow pale malt to absorb water prior to using it. Unfortunately, brown malt was in its heyday before thermometers were invented, so the very few contemporary descriptions that I have seen give no idea of the temperatures involved. Probably fairly critical.

Then there is the question as to what was meant by "blown" malt. It could have meant "popped", like popcorn, as in snap malt, but on the other hand the damp brown malt swelled somewhat when it was shoved on the kiln and this swelling could be what was meant by blown. We know that standard brown malt was diastatic, because it was used at 100% in early beers. I have my doubts as to whether snap malt would retain its diastatic power.

The smokiness is interesting. I suppose the degree of smokiness would depend upon the greeness, dryness or maturity of the wood. Perhaps the London brewers preferred hornbeam because it was clean burning. I may have to modify my views about the smokiness of porter. However, other woods were used in other parts of the country, and I know beech gives a strong smoky tang, because I've tried that.

[Fuggledog]

Mr Wheeler,

thanks again for this very interesting and useful feedback. I was actually wondering if you'd be interested in collaborating in some 'experimental' malting of snapped and or brown malts, perhaps trying out some of these combinations, and if possible making beers from them? I'd also be very, very interested to learn from your own experiments with kilning with beech etc. I think I read somewhere that you'd tried this on several occassions, changing some of the variables. would it be ok for me to discuss this with you further?

I was thinking about making a makeshift 'kiln', so that I could try the proper 4 hour drying process. I think you're probably right that there would be more of a smoky flavour if the malt was on the kiln for this time. Also the aroma of hornbeam on the fire is very pleasant, quite mellow and unobtrusive. i think there is a lot of scope for us to work together on trying out some of these ideas. would you be interested? of course i don't share your expertise but i'm very happy to potter about in making some of these malts.

I thought your comment on the appearance of the blown malt, and the reasons contributing to it vis-a-vis snapped malt very interesting. I did notice that the 'snapped' malt (or pseudo snapped malt) i made didn't noticably 'swell up'. So perhaps snapped and brown were different as you suggested? Or blown, snapped and brown were all categories of a general high dried 'brown' category?

in the meantime, if i was to start with modern pale ale malt as a short-cut (well perhaps not a short cut as it sounds very different from where you'd start with brown malt), how long do you think i'd need to soak it to rehydrate it enough to the point where i could approximate a green, wet malt ready for the kiln? perhaps i need to investigate malting from scratch (although from the little i've read on the subject that is a massive pain in the ass and very differcult to get right). Either way though, i'd really like to give this a go.

many thanks,

Ben

[Graham]

I don't really have much "expertise" in this matter. My early experiments were done years ago, and I was just interested in smoking. it was before the days that I had formulated my ideas that something akin to the crystal malt process must have been going on within the grain of brown malt; the Maillard reaction and all that jazz.

In those days I had one of those American-style cylindrical, enclosed smoker / barbecue things. This was ideal because you can control the airflow which is important for both regulating the temperature and causing the wood to smoke. The wood smokes most profusely when it is starved of air. My first attempt failed because I bought some kind of aromatic wood chips from the garden centre from which I bought the smoker. Might have been okay on a kipper, but certainly too overpowering for malt. In the end I sourced some local beech off-cuts, and this was much better, and quite strong, but still not hornbeam.

I believe that the reported swelling of brown malt was due to the moisture within the grain expanding, maybe even turning to steam. Also, of course, in snapped malt the grain must swell just before it pops, although that probably happens too fast to see it.

I agree that blown and snapped are categories of high-dried brown. Brown malt should be held distinct from snap malt and perhaps blown malt. Brown malt came in various grades depending upon how "highly dried" it was. The anonymous author of Every Man his own Brewer, writing in 1768, tells us the length of time that he expected for a beer to fine depending upon the colour of the malt used: Pale yellow...two months ; Bright yellow...four months ; Amber...four months ; Brown...four months ; Middling Brown...six months ; High Brown...twelve months ; Dark brown...eighteen months ; Brown With Black Specks...two years. Brown with black specks? Try asking for that at your local home brew shop! Nevertheless, that shows that there were several grades of brown malt.

Ordinary brown malt, not high-dried, didn't snap, except by accident, it was considered a fault. There was a phase of some maltsters using perforated cast-iron plates for their drying floor, sometimes a wire mesh. However, because the furnace of the kiln was rarely extinguished, just damped down, these metal plates got very hot, and when the grain was first thrown onto the floor, a proportion of it snapped. A batch of malt with too many popped corns was rejected. The best malt was dried on horsehair mats.

Very high-dried brown malt seemed to have had a brief period of use in porter, probably for colouring. However, it was not used alone, but in conjunction with other malts. It probably became popular when pale and amber malts were beginning to replace some of the brown malt in porter, and high-dried malt was used in small amounts an attempt to maintain colour. This could well have snapped during production, certainly maltsters had a habit of burning down their malthouses while making the stuff, so things must have been pretty hot.

Of course, much of this is interpretation. Without a tardis, better historical references, or lots of experiments we will never know.

[Zapp Brannigan]

What a fascinating read

[Fuggledog]

As Zapp said: this is a really fascinating read, thank you so much for your contribution Mr Wheeler, this is both very interesting and helpful.

I'm now quite 'fired up' as it were to try making a variety of these different forms of brown malt. I could test the diastatic ability of them, and perhaps make a few different beers for comparison. if you were interested Mr Wheeler i could also send some to you in the post to sample yourself? the smell from this first batch is wonderful, but I'll have to wait until tomorrow to see if I've 'killed' all the enzymes. I really like the idea of the blown malt and the potential crystal malt like flavours. that will have to be my next batch. Then again I'd really like to try and make the ordinary brown malt you described for beers using it as 100% of the grist. I'm not sure how dark that would be - the diastatic amber from Belgium looks really pale, so i assume a quick hot kiln would be necessary like the snapped malt (but without the snapping or with minimal snapping) to get more colour than diastatic amber without killing the enzymes. I did observe that when i didn't have the fire hot enough, the malt didn't snap but 'baked'. I guess the problem would be balancing between a more modern brown/amber malt that is baked, and one of these older style malts that use a short heat without snapping or blowing. from my 1 attempt at the snapped malt its not clear in my mind how that would work, but I'll give it a go.

in the meantime I'm hoping that the snapped malt i have here has retained enough enzymes to self-convert. it looks very promising as a malt for pseudo old-style porters. I guess 'pseudo' is the right word as we'll probably never know the 'truth' as you mentioned, but i think these practical experiments might be useful for interpreting descriptions in the old texts. [Edit: it did retain enough enzymes to self-convert! Started a new thread with pics].

re. burning down malt houses - i can very much believe that after seeing what happened with the snapped malt. one description i read had a small team of people frantically turning the malt as it snapped. i found i had just seconds to turn it before it smouldered then caught alight!

kind regards,

Ben

[Trefoyl]

Interesting article about the revival of a Victorian Malt:
http://zythophile.wordpress.com/2013/04 ... er-styles/

[seymour]

Bump. Because this is just too cool.