A History of Malt Extract

There is a problem with beer, at least to some number crunchers. The problem is that it is mainly water — 90% or more for most beers. If brewers could ship just an essence of beer, it would drastically increase profits by cutting packaging, storage and transport costs. The obvious alternative would be to produce a concentrated wort that could be cheaply transported, then diluted and fermented on site where it is to be drunk. In other words, what we inaccurately call “malt extract.”

We take the shipping of perishable goods — such as beer and food — for granted, but this was much more difficult in previous centuries, where transport was at best a horse-drawn cart on badly made roads. Even worse, beer was shipped in wooden barrels, adding significantly to the weight that had to be carried. Barrels were expensive and were often lost or stolen, further eating into the brewer’s profit. So it is not surprising that the idea of wort concentrate has a long history.

In the beginning

It could be argued that the first approach to a concentrated wort were the beer “loaves” thought to have been used by the Sumerians some 3,000 years or more ago, and later by the Egyptians. Preparations based on concentrated wort (and occasionally beer) were common in England by the 17th century. However, these were flavored with various roots and herbs and used as the basis of various patent medicines. In 1755, a chemist named Mr. P. Shaw proposed that the “surplus” water could be frozen out of beer. And brewers have told us that ice beer is a modern concept!

Endeavour, Resolution and Adventure

The organization with the greatest historical need for transporting beer over long distances was the British Navy. It’s been said that the effective sailing range of a naval ship was only as far as its stock of beer would take it. Provisioning beer was a logistics problem for the Navy when a ship was away from dock for a month or more. There would a centuries-long connection between malt extract and the Navy.

In the 18th century there was another reason for making a beer concentrate. On long voyages, scurvy was a real problem. Beer and wort were thought to be excellent anti-scorbutics, so if an extract could be made that would keep longer than the normal two months that beer lasted, this problem would be solved. Thus, the Admiralty were very interested when, in 1772, Henry Pelham (with the grand title of Secretary to the Commissioners of Victualling) said that he had made samples of two different malt extracts. One was a hopped malt extract from wort, and the other was an extract from beer. Both were produced by evaporation, but the first needed to be diluted and fermented with yeast, while the second only required dilution and standing a few days before it was ready to drink.

The Admiralty thought this was a wonderful idea and a chemist, H. Jackson, was set to work to produce these extracts in sizeable quantities. He used some deep boilers, which had been used to produce a kind of soup extract to be used on ships, to make the malt extract. Because of the time it took to boil off the water, they were very dark and had a burnt taste. Jackson made some beer from the extract and said it tasted like beer made with treacle. He manufactured 25 barrels of the hopped extract, and six half-barrels of the beer extract. These went with Captain Cook on his second voyage to the Far East (1772–1775), but the experiment was not a success.

The first problem was that both extracts started to ferment, even before dilution! A good deal of it was lost, as the escaping gas blew out the bungs of the cask. However, enough was saved to actually brew some beer, which raised the second problem. It had such a burnt and bitter taste that the crews of the ships (Resolution and Adventure) did not like it. A few years later, Captain Bligh took some of the extract with him on the ill-fated voyage of the Bounty. Could it be that the infamous mutiny was the result of Bligh cruelly forcing the men to drink beer made from the extract, rather than his more conventional harsh treatment of flogging and keel-hauling?

Captain Cook also made a spruce beer, using an infusion of spruce leaves along with molasses and one of the extracts (in 1:3 ratio), and then adding dried yeast for the fermentation. This must have been more successful, for it was made several times. I don’t know if there is any connection, but Cook came from Whitby in Yorkshire and a spruce beer is still sold there. This is known as Black Beer and some extract is used in its production, but no molasses.

Despite these rather discouraging results, the Admiralty persisted in looking at the benefits of malt extract and Cook took more with him on his third voyage in 1778. This was not, of course, a successful trip for Cook himself as he was killed in Hawaii. Captain King, who brought back the Discovery, was forthright in his praise for the project, attributing the very good health of his crew “in great measure to the beer we brewed.” This time the extract did not appear to have fermented in storage, so perhaps Jackson had refined his production technique by this time.

In 1778, Robert Thornton came up with an improved process, which he patented in that year. This used steam-heated double boilers and his product was a brittle, glass-like solid. This was stable on storage and the Admiralty loved it. According to the Commission-ers of Victualling, beer made from this new extract had “the genuine pure flavour of the malt and hops” and was “remarkably agreeable to the palate.”

We have to wonder about the accuracy of this statement. Thornton’s extract was probably less burnt than Jackson’s earlier effort, but it was still produced at atmospheric pressure, not under vacuum as extracts are today. It would have taken a very protracted boil to remove virtually all the water. At best, the product would have been highly caramelized.

Nevertheless, the Admiralty were sold on the idea and issued an order in 1779 that all ships on channel or foreign service should leave port with six months supply of the new extract — over three tons! According to the Commissioners, this would improve the health of the men without increasing the cost of supplying them with beer. Thornton, as the patentee, received this lucrative contract.

It was a grand scheme, but it didn’t work. Just two years later the Commissioners had to admit that the scheme had failed. Their report to the Admiralty claimed success for the extract as an anti-scorbutic medicine, but also stated that this was the only reason for which it would be allowed on naval ships. It seems the beer made from the extract was not acceptable to the sailors.

But the Admiralty were not so easily discouraged. They decided to have another shot when in 1796, Sir John Dalrymple presented them with a plan for brewing beer “on board.” The admiralty issued instructions that the ingredients and apparatus proposed by Dalrymple should be shipped to the West Indies so that a proper trial of the process could be carried out. One of his assistants was actually accredited with the rank of midshipman so that he could carry out the work. Sadly, there are no more details and it is not known what, if anything, the trial achieved. Just two years later, the Admiralty ordered a stop to issuance of malt extract as an anti-scorbutic, having found that lemon juice was more effective and much less expensive than extract.

Perhaps we should be aware that the problems might not have been wholly due to odd flavors from the extract. At that time there was a lack of understanding of the role of yeast in the process, unsanitary conditions on board and no means of controlling fermentation temperatures on a small ship rolling around in the South Pacific. In other words, the process may have been just as much to blame as the raw material. It would be 150 years before the Navy finally succeeded in brewing beer from malt extract on board ship.

Extract and the Porter Revolution

Around the time all of the above was happening, there had been an important change in brewing technology with the introduction of the hydrometer. For the first time, brewers knew what kind of yields they were getting from their malt. One thing they found out was that brown malt gave much less fermentable material than pale malt on an equivalent volume basis. Pale malt might cost more for the same volume, but it was actually cheaper to use than brown malt.

Brown malt had been the main staple in porter production, a beer that was then at the height of its popularity. This left the brewers with a problem — if they replaced all or most of the brown malt with pale malt, their porter just would not taste or look the same. To compensate for the change in base malt, they had tried all sorts of substitutes — including “burnt” malt or barley or burnt sugars. All sorts of other additives were also tried, some of them quite nasty. But the authorities reacted strongly to this. It was malt and hops that were taxed, not beer, and they did not want to lose out on a valuable source of revenue. Consequently, they introduced a whole raft of laws proscribing the use of anything other than malt and hops.

This made life difficult for the big porter brewers in London, who were also being pressed by big increases in the price of malt. The answer to their problem was blindingly simple; in 1802 Matthew Wood came up with a malt extract in syrup form that was intended for use as a porter coloring and flavoring agent. Exactly how Wood made his extract is not known. He had no roast malt available, so did its coloring and flavor properties simply arise through caramelization as a result of long boiling time during evaporation? Given that the extract was made from malt and that water removal must have been expensive, it is difficult to see that it would have saved brewers any money, as compared to using brown malt in the usual way. It therefore seems likely that he used only a portion of malt in the extract, and supplemented it with something giving a much stronger and more powerful flavor.

There are two obvious ways in which he could have done this, and the first would have been to add something like molasses. And, indeed, he did later offer an extract made from molasses. The second is a little more sinister — perhaps he was adding one or more of the proscribed adulterants. This is merely supposition, and there is no direct evidence that Wood did doctor his extract. He did successfully sell it to various brewers, but at this time there had been a huge increase in the use of adulterants, as the price of malt and hops rose still further. That meant that the Excise clamped down heavily on the use of added chemicals, and also on Wood’s coloring agent, prosecuting several brewers who had used it. But Wood, many country brewers and some of the lesser country brewers pushed Parliament to relax the rules on coloring additives after 1807. They were opposed by a few of the big London porter brewers, such as Whitbread. But even they gave up in 1810, when malt prices were set to rise still further. Finally, in 1811, coloring made entirely from muscovado sugar was permitted. The bill permitting sugar addition was repealed in 1816. Only a year later, Daniel Wheeler patented a process for making high-coloured malt by means of roasting it in a cylinder. All the porter brewers soon adopted his patent malt, which later became known as black malt and Wood’s agent disappeared from the market.


Cook’s High Seas Ale (Historical reconstruction)

Modern extracts are of a much higher quality and give a very different flavor than the extract Cook had. Given the reception this beer received from Cook’s sailors, you might think it is not worth the effort to try to exactly duplicate this beer. I haven’t tried to do so myself, but if you do want to have a go, here is a possible approach.

Ingredients (5 gallons/19 L)

6.6 lb. (3 kg.) plain amber malt extract (or extract designed for mild ale)
5 oz. (142 g) pale dry malt extract
6.3 AAU Goldings hops (1.25 oz./36 g of 5.0 % alpha acid)
Whitbread dry yeast
1 cup corn sugar (for priming)

Step by Step

Dissolve the malt extracts in 3 gallons (11 L) warm water, stirring well to ensure the extracts dissolve properly. Bring to a boil, add the bittering hops, and boil one hour. Strain, or siphon off from the hops, and add cold water sufficient to obtain the starting gravity. Now, using a shallow pan (such as is used for making maple syrup), boil over an open wood fire, until the volume has been reduced to about 0.5 gallon (1.9 L). Remove from heat, and carefully wash extract into a fermenter with cold water. Adjust wort volume with cold water to target gravity of 1.045, and cool to about 70 °F (21 °C). Pitch with yeast starter, and allow to ferment. By 5–7 days, final gravity should have been reached; rack into a glass fermenter. One to two weeks later, rack again, prime with corn sugar, and rack into keg or bottles. The beer should be ready to drink after conditioning for a week or so.

Captain Cook’s Spruce Beer

The recipe below is pretty much as Cook quoted it in his journal, except that I have adjusted it to give five gallons of finished beer. Note the use of tea to moderate the spruce flavor.

Ingredients (5 gallons/19 L)

a few handfuls of spruce leaves
an equivalent amount of tea leaves
0.5 lbs. (0.23 kg) molasses
2.6 lbs. (1.2 kg) liquid malt extract
dried ale yeast

Step by Step

“Take a few handfuls of spruce leaves or small branches, and add the same amount of tea. Boil with 3 gallons (11 L) of water for 3–4 hours, and strain the liquor from the leaves or branches. To this decoction add 1/2 lb. molasses (0.23kg) and 2.6 lb (1.2 kg) malt extract, and bring the mixture just to a boil. Adjust the volume to 5 gallons (19 L) with cold water, and add dried yeast. In a few days the beer will be fit to drink.”

A more convenient approach is to use essence of spruce (available from some homebrew suppliers), at the rate of up to 5 teaspoons per 5 gallons (19 L). This seems a very long boil, and I would recommend no more than an hour. I calculate this to give an OG of only 1.024!

I have not attempted to brew this beer (I don’t particularly like the flavor of spruce!), but if I did, I should add more malt extract to balance the strong spruce flavor. I would recommend using another 3.3 (1.5 kg) lb of amber malt extract, giving an original gravity of about 1.045.

Porter Coloring Agent

This is pretty much a guess as to how Wood might have made his “porter coloring,” so I cannot claim it to be original. For health reasons it does not include any of the head-retaining and flavor additives Wood might have added.


1.0 lb. (0.45 kg) blackstrap molasses
2.0 lbs. (0.9 kg) amber malt extract

Step by Step

Dissolve extract and molasses in 2 gallons (7.6 L) of hot water, and bring to a boil, stirring well to ensure their full dispersion. Boil vigorously until the mixture has reached a volume of 1–2 quarts (~1–2 L). Cool and store in a sealed, sterilized jar. Use the porter coloring agent as required to add “porter” color and flavor to a base beer made primarly from pale malted barley (or light malt extract).

Issue: October 2004