Throughout the year I post new drink books to Alcademics, because I love drinking and books. Below is all of them put together so that you can make your holiday wish list for yourself or see them all together to pick presents for friends and family.
Know of a book I missed? Let me know and I'll add it.
Culture and Fun
You Suck At Drinking: Being a Complete Guide to Drinking for Any and All Situations in Your Life, Including But Not Limited to Office Holiday Parties, Weddings, Breakups and Other Sad Times, Outdoor Chores Like Deck-building, and While in Public, Legally and Illegally By Matthew Latkiewicz
Cocktails of the Movies: An Illustrated Guide to Cinematic Mixology by Will Francis , Stacey Marsh
Imbibe! From Absinthe Cocktail to Whiskey Smash, a Salute in Stories and Drinks to “Professor” Jerry Thomas, Pioneer of the American Bar (Updated and Revised Edition) By David Wondrich
Contraband Cocktails: How America Drank When It Wasn't Supposed To by Paul Dickson
Narrative Cocktail Books
The Cocktail Chronicles: Navigating the Cocktail Renaissance with Jigger, Shaker & Glass by Paul Clarke
Ten Cocktails: The Art of Convivial Drinking by Alice Lascelles
Cocktails from Specific Bars
The Dead Rabbit Drinks Manual: Secret Recipes and Barroom Tales from Two Belfast Boys Who Conquered the Cocktail World by Sean Muldoon, Jack McGarry, Ben Schaffer
Experimental Cocktail Club: Paris, London & New York by Romée de Goriainoff, Pierre-Charles Cros, Olivier Bon, Xavier Padavoni
Cuban Cocktails: 100 Classic and Modern Drinks by Ravi DeRossi, Jane Danger, Alla Lapushchik
Tujague's Cookbook: Creole Recipes and Lore in the New Orleans Grand Tradition by Poppy Tooker
I wrote a story for Popular Science on the science of barrel aging. The story was inspired by a trip to The Glenlivet where I tasted a 50-year-old whisky without any smoky qualities – but 50 years ago this and most whisky would have been at least lightly peated.
So I went into the article specifically looking for what happens with the smoke, but ended up writing about wood interactions as well.
To do the story, I read several wood science articles sent to me by Diageo whisky ambassador/smart-guy Ewan Morgan, spoke with Dr Bill Lumsden from Glenmorangie, interviewed Bryan Davis from Lost Spirits, and illustrated the story with a chart from Lew Bryson's excellent book Tasting Whisky.
Hopefully I didn't get anything wrong. Read it here.
If it were easy to make good whisky anywhere, it would be made everywhere. And if it were easy to make good single-malt whisky in four years, everyone would do it. But Kavalan makes some very well-respected juice in four years in the mostly-hot country of Taiwan.
On my trip to the Kavalan whisky distillery that you can read out here and here, I spent a lot of time asking questions about what the differences in production are between Kavalan and scotch whisky, and other places where they had to compensate for their unique aging environment. Here are a few observations:
Preparation
They know that that they'll only be aging their whisky for 4-7 years, most of it closer to 4. They also know that their climate is hot and humid, though there can be a temperature range during the year that will suck the whisky into and out of the barrels causing interaction. They also know there will be a significant evaporation rate (angels' share) so that's another reason not to leave it aging too long.
In short, they don't have much time to get it right. There is no "fix it in the barrel" mentality, as too long in the barrel will taste just as bad as too little time in the barrel. They've basically got one shot to get it right so they go into it with cautious perfectionism.
Ingredients
American oak barrels give less tannin absorption than do French oak. So their ex-sherry, port, etc. barrels must be made from American oak.
Like other top whisky producers, they fly over to Spain and Portugal to personally source the best barrels.
Yeast – They use an alcohol-producing yeast and a flavor-producing yeast. I am not sure if this has to do with climate at all, or is just a unique method. See fermentation below.
Process
Fermentation is temperature-controlled to ensure consistency in batches. It is a long fermentation using 2 different yeasts and an additionally long period for lactic fermentation. This contributes to the signature fruity flavor profile Kavalan is after. I am guessing that given the short amount of aging time, they want the fruit notes to be most forward and the grain notes (signaling too-young whisky) less prominent.
Heads and tails cuts are different: A tight heart cut (so less heads and tails overall), but a little bit more of the heads and way less of the tails. Most whiskies that will sit in barrels a long time include a fair portion of the tails, as they break down/interact with the wood/oxygen over time and turn into good stuff. At Kavalan they don't have that much time.
Larger barrels (ex-port and sherry) are stored mostly on the hotter top floor of the aging warehouse. Larger barrels take longer to age the whisky inside them, as there is less wood-to-liquid ratio of smaller bourbon barrels.
Cautious Rechar. They do rechar barrels but the whisky aged in them is used for the base-level single-malt and the 46% version of that, not for any of the (so much better) Solist bottlings. Which helps explain why I like the single-cask bourbon barrel bottling so much better than those other two.
The sherry barrels come off a real solera after 20 years or so, then they are seasoned with 20 years old oloroso before Kavalan gets them.
Budget
Kavalan is a small part of a huge company, so they have budget advantages that they have certainly used.
I have sipped so many failed experiments over the years, many from otherwise quality distillers. I hate it when otherwise-quality producers put their failed experiments into bottles and try to pass them off to consumers. At Kavalan they purchased I believe 8 hybrid pot-column stills when they first built the distillery, which that they stopped using after they found that they didn't produce good whisky. (Don't worry, I think they have found another use for them that we'll hear about later.) That was an expensive decision; clearly one of many.
They hired whisky doctor Jim Swan, who is certainly not cheap, to get things running and continually checking in. He was there during my visit distilling a peated malt.
They throw away (or rather, recycle into the next batch) a lot of heads and tails.
The shave-toast-rechar process used on the Vinho Barrique barrels is also quite precious and must be super expensive, as they have to rebuild all those barrels in the process. I don't know too much about this process but have heard it is done in the wine industry (probably minus the recharring).
Consistency/Computer Control
Computers control washing, fermentation, and distillation.
They test everything along the way.
So, I'm sure that's not quite everything they do at Kavalan to make good whisky quickly in a hot climate, but it's a lot of it. So you might not want to run right out and set up your distillery in Sumatra just yet.
This spring I had the unique pleasure of visiting the Kavalan single-malt whisky distillery in Yilan, Taiwan.
This is a long post, so get comfy if you want to read, or just scroll through the pictures.
The week previous to my visit, their Vinho Barrique Solist whisky won the World's Best Single Malt Whisky award from the Beverage Tasting Institute, so everyone was in a really good mood. I think we were the first American journalists invited to visit, so that was double awesome.
The young distillery already receives 1 million visitors per year, 30% of them foreign. It's free to visit and to get a whisky sample at the distillery, which also has a gift shop and a huge cafe.
Kavalan's History
Kavalan is located in the county of Yilan, not far from Taipei, and the name Kavalan is the name of the indigenous people of the region.
Our hosts for the trip were master blender, global brand ambassador, and director of global business development Ian Chang; and consultant whisky maker Dr. Jim Swan.
Kavalan whisky is just one small part of the multi-billion dollar King Car company. (King means "gold", so it's supposed to represent a golden car rolling in to the future.) This company and Kavalan whisky was founded by Mr. Lee Tien-Tsai, whose 50-year old son we met for an epic banquet later in the trip. The company has many different divisions including, in part, consumer products (Mr. Brown Coffee, cans, cleaners and insecticides, instant noodles), health supplements and biotech research, food safety analysis, horticultural research, and more.
The factory where Kavalan is located also produces bottled water (from the local mountains), yogurt, and tea beverages. There is also a small conference center on-site. The factory was established in 1995. Then the rather large distillery was built in 2005 – all in 9 months. The first drop of new make spirit was made on March 11, 2006 at 3:30 PM.
Kavalan is so far the only whisky made in Taiwan, though another company has recently announced plans to begin.
Water, Barley, Yeast, and Fermentation
The water comes from the nearby mountains, naturally filtered through the earth and comes out as spring water. Swan said the water is clean and pure and there is plenty of it. It has a nearly neutral pH, and 17-20 ppm Calcium, which is a little higher than in Scotland according to Chang, but overall it’s soft water.
As covered a bit in my Water Project here on Alcademics, Chang notes that calcium, zinc, and magnesium quantities in the water are important for fermentation. (The yeast needs these minerals.)
The mountains not far from the distillery provide the water used for Kavalan.
They use untreated water for fermentation, and then reverse osmosis-filtered water for barrel proofing and bottle proofing, starting with same water source. (Many other distilleries like those in Kentucky use municipal water for the watering to bottle strength from barrel strength.)
The 2-row malted barley comes from Scotland. When it arrives it is ground in a malt mill, then mashed and fermented just like scotch whisky.
Washing is when hot water is poured on top of the ground-up barley to rinse out the fermentable sugars and leave behind the husks (which would burn against the side of the still). The barley is washed three times in the mash tun.
The copper mash tun was made in Scotland. It takes a 4 ton mash 8 hours each. There are three washes: 65 Celsius for the first, 85C for the second, and 90C for the third wash. The water from the third wash goes into the first wash of the next batch rather than into the next barley wash. This is the same process and more or less the same temperatures used in Scotland, according to Chang.
Fermentation takes place in stainless steel tanks called washbacks. These are temperature controlled to ensure consistency.
Fermentation is a bit different at Kavalan. They use two strains of yeast, both "dry-pitched" (added dry rather than wet). One is a "core fermenter" that produces lots of alcohol from the grains. This ferments for about 10 hours.
The second yeast they called a "fruit producer," meaning the fermentation with this yeast brings out a lot of fruit notes to the fermented barley. They let this ferment for about 20 hours, after which most of the yeast die.
The yeast then undergoes mostly lactic fermentation for an additional 30 hours, so that it's 60 hours total. "We need that long to get the fruit," said Swan.
Fermentation here is temperature controlled for a slow gradient of heat rise. It begins at 18C and ends at 34C. The beer is between 8-8.5% ABV after fermentation, which is slightly high compared to Scotland.
Distillation
Initially they were using hybrid stills – discontinuous stills with pot stills on the bottom and a short column on top. These are no longer used for whisky production.
Stills no longer used for whisky at Kavalan.
In 2006 they brought in 2 pot stills (a set of wash and spirit stills), and then 2 more stills in 2008. They have three more pair of stills coming.
Today they produce 9 million bottles of Kavalan per year. Wow.
Chang told me that since they know with the hot climate their whisky will not age long in barrels, they have to make adjustments to the heads/tails cuts over what one might do in Scotland. They make a tighter cut overall (less heads and tails), do keep in a little bit more of the heads than is typical, and less tails.
They use less tails because they know they won’t be aging it for very long, and tails take longer to purify as they interact with the wood in a barrel.
As it typical they recycle feints and foreshots into the next batch's second distillation.
Their pot ales (stuff at the bottom of the still that's not alcohol) are treated to neutrality then released into water system.
The spent grains from the barley mostly go to pig farmers as they don’t have a lot of cattle on Taiwan.
The spirit comes off the still around 65% ABV and is diluted to 59.5 – 59.9 % before going into the barrel. (This is the flash point for whisky, according to Chang.) Swan says that this makes no flavor difference to the whiskey as opposed to the standard 63% barrel fill proof in Scotland.
Because of demand they run their stills then 24/7/365. As mentioned, more are on the way.
Aging in a Hot Climate
Between October and March they have cold winds coming from Siberia that bring precipitation and humidity along with the breeze. In fact, the average temperature ranges from 58F (14.4C) in January to 83F (28.4C) in July. So it's not like the region is always the same temperature. However the humidity is always high: 89-94% humidity all year round.
Chang says that the sub-tropical climate of the reason accelerates maturation but it's bad for the angel's share – lots of evaporation. It was either Chang or Swan who said, "Subtropical heat is like sandpaper – it sands away all the rough edges into a soft and round crystal ball of whisky.”
After a particularly hot summer they noticed their angel's share was as high as 18%, but normally it’s 10-12%.
Barrels and Warehousing
They age all their whisky in American oak, which Swan says is better in hot weather because it has less tannins than European oak.
The barrels are stored in a 5-storey warehouse. All the barrels are palletized (stand on their ends rather than their sides) except the large puncheons on the top floor.
The bottom and top floors have high ceilings. The bottom floor's ceiling height was because they thought they were going to put big vats there but then didn’t. The top floor have high ceilings because the sun hits the roof and they want to minimize that heat.
On the 5th floor it gets up to 42 degrees Celsius, while on the ground floor it’s 27 degrees at the same time.
I believe they are using one of two warehouses onsite currently, each has the capacity to hold 60,000 casks.
They do not rotate casks, but they put different sizes of casks on different floors. On the top floor are stored sherry butts (500L) and port pipes (600L). The bigger the cask, the slower the maturation, they say. The first through fourth floors hold mostly the ex-bourbon casks.
Rechar Barrels
As you'll read in the next post for specific whiskies, sometimes they rechar barrels at Kavalan. They are used in certain expressions as noted in the next post.
Because this post is already 2 billion words long, I'll save until tomorrow a post about how all these processes come together to make the bottles of Kavalan you see on the shelf.
In 2014 I visited the Bunnahabhain (boo-nuh-ha-bin) distillery on the island of Islay off the western coast of Scotland. Bunnahabhain is the northernmost distillery on Islay (home to whiskies including Laphroaig, Bowmore, and Ardbeg) with the Paps of Jura just across the water. They call Bunnahabhain "the welcoming taste of Islay" because unlike those other scotch whiskies, Bunnahabhain is mostly not smoky and heavy.
Not So Smoky
It wasn't always that way. Until 1963, according to Distillery Manager Andrew Brown, Bunnahabhain made smoky Islay-style whisky. In olden days, they used to malt the barley on-site, but now the old malt hall holds barrel aging facilities.
Now they use unpeated barley (less than 2 ppm phenol) for most of their whisky except special editions. Those take place during only a few weeks during one period of the year. In 2014 the were doing 9 weeks of peated malt distilling, using barley with a phenol level of 35-40 parts per million. Malted barley is delivered to the island and ground on-site.
It is then washed with hot water to wash out (and keep) the fermentable sugars and leave behind the solids. The mash tun holds 50,000 liters.
While most scotch whiskies (at least most that I've visited) wash the barley three times, with the last wash going to the next batch, at Bunnahabhain they wash it four times with the last two washes going to the next batch. Not sure why.
If I got this right, the barley contains 20% fermentable sugars going into the wash, and sugars are washed out (to go to fermentation) at each step:
64 Celsius water brings the sugar content down to 15%
80 Celsius water bring it down to 5%
90 Celsius water for both the second and third washes brings it down to basically zero.
Fermenting and Distilling
The sugary liquid is now ready for fermentation, which is done is one of six wash-backs. The liquid ferments for either 48 hours (on Mondays and Tuesdays so they can distill the fermented beer later in the week) or 110 hours (on Wednesdays, Thursdays, and Fridays, as these will be distilled the next week after the weekend). Brown said this doesn't make a change in the final spirit's flavor after distillation, but they do blend together the spirit made from the two different fermentation times before barreling anyway.
Bunnahabhain is the only distillery on the island to use pure spring water for fermentation. Much of the water for other distilleries starts at one place on Islay and runs over peat bogs on the way down to the distillery, but Bunnahabhain pipes their water 2 miles from the spring so it doesn't run through peat.
The stills here are the tallest on Islay, all packed into a little still room. Two of the stills are quite old, while the other two were added in 1963 along with other equipment when the distillery changed format from Islay-style to unpeated scotch.
When they distill peated whisky during those few weeks of the year, they take different heads and tails cuts on the second distillation as opposed to when they're distilling unpeated whisky.
Water used to bring the newly-distilled whisky down to barrel proof is the same spring water used in distillation but run through a 5 micron particle filter and then a UV light filter.
All of the single-malt whisky made by Bunnahabhain is aged on Islay. They have 21,000 casks aging locally in 6 dunnage and 1 racking warehouses. Whisky for the blends ages on the mainland.
The whisky is bottled on the mainland outside of Glasgow, using the same water that Deanston does (demineralized municipal water).
Bunnahabhain sells about half of the whisky they make to other brands for use in blends. Of the remaining half, 10-20 percent of it is sold as Bunnahabhain single-malt, while the rest goes to their own blends. The parent company Burn Stewart produces Scottish Leader and Black Barrel blends.
Quick Tastes
I visited the distillery during Feis Ile (more on that later), which didn't give a lot of time for quiet contemplation, but here are a few notes on what I tasted.
Bunnahabhain 12 year old: A mix (not a finish) of whisky aged in ex-bourbon and ex-sherry casks. It has a lot of nutty flavors, dried fruits, and a whisp of smoke.
18 year old: Aged in ex-sherry barrels. It is softer yet spicier than the 12 year, and richer due to that sherry influence. My tasting notes, which you should know by now don't make sense to anyone but me, describe it as "rosemary stems and velour tracksuit in dark green."
25 year old: First and second-fill ex-sherry casks. Rich, lovely, wood-soaked and showing the good qualities of age.
Toiteach: From peated barley aged in bourbon and sherry casks. Young canned peaches and ash, a touch of hospital, interesting and well-made.
Helmsman's Dram (a special edition for the festival): Aged 9 years in ex-bourbon then 1 year in a Marsala cask. Seemed Marsala-influenced (old wood tastes), "chicken jerky and chocolate covered salty raisins."
Westering Home (also a festival edition): 10 years in ex-bourbon casks then 6 years in cognac casks then 1 year in Sauternes. To me it tastes like Bunnahabhain with a touch of wine and spice.
It was a great day on Islay and my third visit to the island, yet I can't wait to go back again.
The Deanston distillery is located just a half an hour's drive north of Glasgow, Scotland (and not far from Edinburgh either), near the town of Stirling alongside the River Teith. It's just barely in the Highlands and has that honey-forward flavor I associate with the lower Highland area.
In addition to producing single malt scotch whiskies, Deanston is the "spiritual home" of the Scottish Leader blended scotch brand. The distillery is open to the public for tours.
The River Teith is the source not only of water for distillation, it is the power source of the distillery. River water flows into the distillery and passes through a hydro-electric station. They use only 25% of the power generated to supply the distillery (they say it is the only self-powered distillery in Scotland), and sell the rest of it back to the national power grid.
Previously the water powered a huge water wheel to accomplish the same thing. The distillery was originally built as a cotton mill. Here's a brief overview of the history:
1785 The Deanston Cotton Mill opened. The cotton mill employed and housed a whole town (the houses are still a few hundred yards away), printed their own currency, and offered schools and other services for the workers.
1965 The mill closed.
1967 The mill reopened as a distillery. The weaving shed became the barrel warehouse.
1974 The first Deanston single malt was released
1982 The distillery closed in the bad whisky economy that was about to turn around
1991 The distillery reopened in the good whisky economy from the 1980s
2000 Deanston received certification to produce organic whisky
2008 Deanston begins bottling only non-chill-filtered single-malts
Making Whisky at Deanston
For Deanston's single malts they use all un-peated barley (less than 2ppm phenol), and soft river water that flows over granite (so no peat in there either).
Their malt mill is a Porteus mill, which is so sturdy they've only had to recalibrate it twice since the 1960s. Unfortunately for the company they made their machines so well they went out of business as people didn't tend to need to buy new ones. The mill grinds the malted barley but does not separate out the husks.
They have a rare, huge open-top mash tun that holds 11 tons of barley/water though they do 9-ton mashes. Mashing is where the ground barley is washed with hot water to release sugars and leave behind the solids. As is typical, they wash the grains three times with different temperature waters:
64 Celsius water: Gets the enzymes out of the barley without destroying them, along with some sugars. (These enzymes will help break up the larger sugars so they can be fermented by yeast.) The sugary/enzyme water goes toward fermentation.
78 Celsius water: To remove the majority of the sugars. The sugary water goes toward fermentation.
88 Celsius water: To remove last bits of sugar. The sugary water goes into the next mash (the next batch) rather than into fermentation.
There are 8 washbacks, 60,000 liter steel (not stainless) tanks. Yeast is added to the sugary water for fermentation. Yeast comes in liquid form via tanker. Yeast is combined with the wort (sugar water) at about 19-20 degrees Celsius. During fermentation, the liquid naturally heats up then cools at the lend.
They do a long fermentation- 100 hours- that includes a secondary fermentation to bring in fruity, green-apple notes.
Distillation and Aging
Then it's time for distillation. At Deanston they have 4 stills – 2 wash stills (first distillation) and 2 spirit stills (second distillation).
The first distillation in a 15,000 liter still brings the fermented beer from 8% ABV up to 23-25%. They don't make any heads/tails cuts in the first distillation. The second distillation in a 14,000 liter still takes the spirit up to an average of 68% ABV.
The lyne arm/swan's neck of the still tilts slightly upwards at an angle, which also helps produce a lighter, fruitier style of Highland whisky.
During distillation, they manually adjust the stills to prevent over-foaming – the distiller looks into the windows of the stills and cuts down the temperature if it's foaming all over the place. They boil the spirit at a relatively low temperature to increase reflux/copper contact, which also helps produce a light spirit.
New make spirit goes into barrels at 63.5% ABV. The water used to reduce the spirit to barrel proof is river water that has been treated with a UV filter to ensure nothing grows in it. The barrels, 50,000 or so of them for their single-malts, are stored in the former weaving shed – a unique aging facility in Scotland.
This building has a ceiling (unfortunately difficult to photograph) similar to sherry bodegas with tall cathedral-style arches and central poles that collect water from the roof down through their middles. The high ceilings were to maintain consistent temperature year-round (better for the sewing equipment) and were covered with grass.
There is only a 5-6% temperature change in the warehouse during the year, which gives them less than a 2% evaporation rate (angels' share).
To bring the whiskies down to bottle strength, they use municipal water that has been demineralized on-site using a resin bed filtration system. They do not chill filter their whiskies, but they run them through a paper filter before bottling at room temp.
Deanston Whiskies
12 Year – The flagship product, with tastes of biscuit and ginger spice. All the whiskies have a honey note.
Virgin Oak – No age statement whisky aged in ex-bourbon casks of various ages, then finished in virgin oak casks from Kentucky for 9-12 weeks. My host and brand ambassador for the Burn Stewart Distillers whiskies, Dr. Kirstie McCallum, calls the Virgin Oak a "summer whisky."
Spanish Oak – Aged 10 years in ex-bourbon casks then 9 years in ex-Spanish brandy barrels, with dried fruits and nutty sherry notes.
Sherry Cask – I think this was a limited edition, aged for 10 years in ex-Oloroso sherry barrels
1974 – Aged 37 years in ex-Oloroso sherry casks, yet it still comes in at 50.3% ABV (showing their super low angels' share). It has rancio, ashy, high vinegar notes of super old sherry.
My trip was hosted by the parent company, Burn Stewart Distillers, who also own Bunnahabhain, Tobermory, Ledaig, Scottish Leader, and Black Bottle. I also visited Bunnahabhain and will write about that more in another post.
By the way, Deanston was my 100th distillery visit!
A few years back I wrote a long feature about the Blood and Sand cocktail, made with scotch, cherry brandy, orange juice, and vermouth.
It was written for the German magazine Mixology, but recently they have put the story online in the original English.
For the story I covered the origins of the drink as best as I could find them, and many variations of the drink. There is a large discussion of the best type of orange juice to use, alternates to sweet vermouth and Cherry Heering, and how to find out if your flamed orange peel is spitting wax and pesticides onto your drink.
This has been a great year for cocktails and spirits books- tons have come out, and the majority are written by well-respected bartenders and other experts. I haven't had time to read the majority of them, unfortunately, but below is a list of all the ones I know about.
Notable Cocktail and Spirits Books Published in 2014:
Whisky Books:
Whiskey Distilled: A Populist Guide to the Water of Life by Heather Greene
The Spirit of Gin: A Stirring Miscellany of the New Gin Revival by Matt Teacher
Distilled: From absinthe & brandy to vodka & whisky, the world's finest artisan spirits unearthed, explained & enjoyed by Neil Ridley and Joel Harrison
In the process of making many types of alcohol enzymes are used, but I didn't know very much about them. So I decided to do some reading and share what I've learned. Or what I think I've learned anyway.
Enzymes are used in spirits production before fermentation. They are used to expose fermentable sugars in base ingredients so that they can be fermented by yeast. For example, a raw potato with yeast added to it won't produce potato beer (or not much of it). But when heated and with enzymes added then it will.
Let's review spirits production:
The base ingredient is prepared for fermentation. This can be as simple as crushing a grape or stalk of sugar cane, but many other raw ingredients must be prepared by methods such as malting (barley), baking (agave), heating in water (many things, called 'mashing' in whisky), and/or adding enzymes.
The ingredient now has its fermentable sugars exposed, so yeast can do its job and convert these sugars into alcohol.
The result is a beer/wine with a low percentage of alcohol.
The beer/wine is concentrated through distillation.
What Are Enzymes?
Catalysts that perform and speed up chemical reactions. They are present in biological cells. They do a lot of work in nature.
They convert molecules into other molecules. An example of this is the enzyme lactase, which breaks a lactose down into two glucose molecules. People who are lactose-intolerant do not produce the enzyme lactase so they can't process lactose.
Enzymes aren't fuel for reactions – they're not consumed by the reaction they catalyze.
Enzyme activity can be affected by environmental things like temperature, pH, and pressure. (For most fermentable materials, the mash of hot water and raw material is heated to very specific temperatures so that the enzymes will work.)
The enzymes are B,C,and D in this illustration. The material A is broken up. Source.
Common Uses for Enzymes
Some easy-to-understand cases where enzymes are used:
In meat tenderizers that break down proteins into smaller proteins, making it easier to chew.
In stain removers to break down fats or proteins on clothing.
In digestion. From Wikipedia, "An important function of enzymes is in the digestive systems of animals. Enzymes break down large molecules (starch or proteins) into smaller ones, so they can be absorbed by the intestines. Starch molecules, for example, are too large to be absorbed from the intestine, but enzymes hydrolyze the starch chains into smaller molecules, which can then be absorbed."
Enzymes in Beer Production
The website HomeBrewTalk.com has a great, detailed chapter on enzymes in fermentation. They lay out how grains for beer are often mashed (heated with water) to two different temperatures.
Mashing is the process in which the milled grain is mixed with water. This activates enzymes that were already present in the barley seed or have been formed during the malting process. These enzymes work best in particular temperature and pH ranges. By varying the temperature of the mash, the brewer has control over the enzyme activity.
In barley starch makes up 63% – 65% of the dry weight. Starch is a polysaccharide (very large chains of glucose) which is insoluble in water. Brewer's yeast, however, can only ferment monosaccharides (glucose, fructose), disaccharides (maltose, sucrose) and trisaccharides (matotriose).
In order for that starch to be converted into water soluble sugars (fermentable and unfermentable), two processes need to happen. First the starch is gelatenized to become water soluble. For starch found in barley and malt this happens above 140ºF (60ºC). Secondly the activity of the amylase enzymes break the long chained starch molecules into shorter chains.
Enzymes in Scotch Whiskey
The malting process in scotch whiskey is a process to expose enzymes. To make malted barley, the dried grains are soaked in water so that the seeds just start to sprout, then the grain is dried to halt the process. Then when the grain is later mashed (has hot water added to it), the enzymes will convert the starches in the grains into fermentable sugars.
According to Ian Wisniewski in Michael Jackson's Whiskey,
"Growth hormones released by the grain also trigger the creation and release of enzymes that begin breaking down the cell walls and protein layers, in order to access the starch… The enzymes collectively termed 'diastase,' include alpha-amylase and beta-amylase (the latter is already present in barley). These enzymes are essential for the subsequent conversion of starch into fermentable sugars during the subsequent process of mashing."
Enzymes Used in Many Spirits
In other spirits, enzymes are added, which saves the malting step or speeds the natural reaction with enzymes naturally present. This is true in bourbon (from corn), in other spirits from grain (like vodka), and for potato vodka.
Most bourbon mashbills (recipes) contain a certain portion of malted barley. This is because the malted barley provides the rest of the batch with enzymes needed to break down the material into simpler sugars. However, in modern times many (if not all) major bourbon producers also add enzymes to the corn, wheat/rye, and malted barley mashbill to speed things up.
A good overview of the chemistry of this and list of enzymes available for purchase can be found on this IM biotech company site.
From the few potato vodka distilleries that I have visited, it seems that adding enzymes is standard in the process of preparing potatoes for fermentation. So I used this project as an excuse to learn more about enzymes.
If you think about a raw vs. cooked potatoes, they get a bit sweeter after you cook them so we can guess that heat helps break down the starch into sugars- at least partially. Enzymes help with the rest.
Karlsson's uses "virgin new potatoes" to produce their vodka. These are very small, skinless potatoes that are full of flavor that translates into the final spirit.
In a post for PopularScience.com I wrote about a technology being employed to toast wine and now whiskey barrels with infrared light. 
