"The making of Malt; by Sir Robert Moray. Phil. Trans. N° 142. p. 1069.
MALT is made in Scotland of no other grain than barley, of which there are two kinds; one with four rows of grains on the ear, the other with two; the former is the more commonly used, but the latter makes the best malt: The more recently barley hath been threshed, it makes the better rnalt 1 but if it has been threshed six weeks, or upwards, it does not make good malt, unless it be kept in one equal temper; whereof it easily fails, especially if kept up against a wall, for that which lies in the middle of the heap is freshest, that on the outsides and top is over dry, and that next the wall shoots, and that at bottom rots; so that some grains do not come well, as they call it, that is, they never attain to that right mellow temper, malt should have, and thus they spoil all the rest; and some grains come well; some not at all, some half, and some too much; the best way to preserve threshed barley long in good temper is not to separate the chaff from it; but as long as it is unthreshed, it is always good: Brewers use to keep their barley in large rooms on boarded floors, laid about a foot deep, and turned at intervals with shovels: Barley that has been overheated in the stacks or barns before it be separated from the straw, will never prove good for malt, nor any other use; but tho' it heat a little after it is threshed and kept in the chaff, it will not be the worse, but rather the better for it; for then it will come the sooner, and more equally; a mixture of barley that grows on several grounds, never proves good malt, because it comes not equally; so that the best barley to make malt of, is that which grows in one field, and is kept and threshed together: Take then good barley newly threshed, and well purged from the chaff, and put eight bolls of it, that is, about six English quarters, into a stone trough; where let it infuse till the water be of a bright reddish colour, which will be in about three days, more or fewer, according to the moistness or dryness, smallness or bigness of the grain, and according to the season of the year or temper of the weather; in summer malt never makes well; in winter it will require a longer infusion than in spring or autumn: One may know when it is sufficiently steeped by other marks than the colour of the water; as the excessive swelling of the grain, or its too great softness when over steeped; being, when in the right temper, like that barley prepared to make broth of; when the barley is sufficiently steeped, take it out of the trough, and lay it on heaps, and so let the water drain from it; then in two or three hours turn it over with a shovel, and lay it in a new heap about 20 or 24 inches deep; and this they call the coming heap, and in the right managing of this heap lies the greatest skill; and in this heap it will lie 40 hours, more or fewer, according to the fore-mentioned qualities of the grain, &c. before it come to the right temper of malt; whilst it lies in this heap, it is to be carefully looked to after the first 15 or 16 hours; for about that time the grain will begin to put forth the root, which when they have equally and fully done, the malt must within an hour after be turned over with a shovel, otherwise the grains will begin to put forth the blade or spire also, which by all means must be prevented; for hereby the malt will be utterly spoiled, both as to its pleasantness of taste and its strength; if all the malt should not come equally, because that which lies in the middle being warmest will usually come first, let it be turned over, that the outmost malt may lie inmost, and so leave it till all come alike: As soon as the malt is sufficiently come, turn it over, and spread it to a depth not exceeding five or six inches, and by the time it is all spread out, turn it over and over three or four times, after this turn it once in four Or five hours, making the heap thicker by degrees, and continuing to do so constantly for the space of 48 hours at least; this frequent turning it, cools, dries, and deadens the grain, whereby it becomes mellow, melts easily in brewing, and then separates entirely from the husk; after which throw up the malt into a heap, as high as you can; where let it lie till it grow as hot as your hand can bear it, which usually happens in about 30 hours; and this compleats the sweetness and mellowness of the malt; after the malt is sufficiently heated, spread it to cool, and turn it over again in six or eight hours after; then dry it upon a kiln, and after one fire, which must serve for 24 hours, give it another more flow, and a third if needful; for if the malt be not thoroughly dried, it cannot be well ground, neither will it dissolve well in the brewing, and the ale it makes will be red, bitter, and will not keep: The best fuel is peat, the next charcoal made of pit-coal or cinders, heath, broom, and furzes are naught; if there be not enough of one kind, burn the best first, for that gives the strongest impression as to the taste."
"Memoirs of the Royal Society: being a new abridgment of the Philosophical Transactions, Volume 2", 1739, pages 134 - 135. (This article was probably written between 1660 and 1673 - the Royal Society was founded in 1660 and Sir Robert Moray died in 1673.)
I'll let the author off for using bolls. The article was written before the Act of Union of 1707. Though he doesn't quite get the conversion right: 8 bolls are really 5.77793056 English quarters. I know. I'm a nit-picking bastard.
They only malted barley in Scotland? What about bigg (or bygg)? That was still big (sorry, I couldn't restrain myself) in Scotland until the early 19th century. OK, it's a type of barley, but there was a differentiation made between the two, even in law. (The tax on bigg malt was lower than that on barley malt because, well, it wasn't as good.) Or is bigg what he means by four-row barley? Mmm . . . . The Oxford Companion to Beer says that bigg is six-row . . . and . . . "Beer brewed from bere barley [same thing as bigg] has a distinctive, pleasant, smoky flavor with a slightly bitter aftertaste." Intriguing. Except no source is given for the stuff about the smoky flavour. That bigg has six rows I have been able to confirm in one of the references given.*
Not being an expert on malting, I've no idea how standard/weird/unusual the practice described is. Steeping, germination, kilning - sounds pretty normal to me. But, like I said, I'm no malting expert.
I'm sure you know why I've reproduced this: because it specifically mentions peat as a fuel. Not just that, it says it's the best fuel. Not the cheapest or the most convenient, but the best. Followed by "charcoal made of pit-coal" which must be coke. Heath, broom and furzes (what the hell is that?) are rubbish. That's all low-quality fuel, likely to create lots of smoke.
Notice what's missing from that list? Wood. Slightly surprising, that. Or had Scotland been deforested by then?
The implication of the text is that peat and coke are the best fuels because they flavour the malt the least. Anyone know if the claim that the malt picks up most flavour at the start of the kilning process is true. I can see the logic in it. As the grain gets drier and harder I can believe it would absorb less smoke.
There you have it: evidence that peat was used in malting in Scotland. Sorry, I should be more specific: peat was used in kilning malt that was to be used in brewing. The references to beer and brewing in the text are important because a large proportion of Scottish malt was used in distilling, not brewing.
* "5085. Bigg, byg, or barley big, is a variety of winter barley known by always having six rows of grains, by the grains being smaller and the rind thicker, and by its being earlier than the parent variety. Professor Martyn says, he has frequently counted forty-two grains on one ear of bigg, when common or long-eared barley had only twenty-two."
"An encyclopædia of agriculture, Part III, Book VI" by John Claudius Loudon, 1831, page 823. (http://www.archive.org/stream/encyclopdiaofa02loud/encyclopdiaofa02loud_djvu.txt)