Three basic materials are needed for production of whiskey:water,grain,yeast.
In order for the whiskey to develop its typical taste,other components,such as the wood of barrel and peat,also play a role.In Scotland each distillery uses its own water,usually from a nearby spring.The mineral and peat content,the hardness of the water or microorganisms determine the particular character of the water.It is also assumed that the water picks up a particular aromatic touch from the typical Scottish heather and passes it on to the whisky.The most important material for the manufacturing process is barley.Malted barley is the main source of flavours for the single malt whiskies.Corn,rye or wheat are also used in other products such as in Bourbon.Before you can distill a whisky from the basic grain,it must first be malted.Malting the grains is the most important steps in whisky production.
Grain is germinated ; in such a controlled manner that the germination stopped just at the right moment.According to long-standing tradition the barley is soaked in water in large vats,so-called steeps.The water is exchanged two or three times during the soaking.During this process oxygen is added over a period of several hours,which helps the grain to absorb the water more quickly.This can take from one to three days,depending on the size of the grain.When the barley has a water content of around 45% after soaking,it is laid out on the malting floors.Depending on the temperature,it begins to germinate after somewhere between 4 and 9 days and growth hormones released in the grain promote the production and release of enzymes.These destroy the seed coats and give the grain the strength to ensure that it develops roots.and leaf sprouts.The enzymes-alpha and beta amylased-are needed to convert the starch into sugar when mashed.A lot of heat is generated as the barley germinates,so it has to be cooled.The maltsters use malt shovels and rakes to turn the grain regularly.This way,the heat is evenly distributed.When the grain has opened and the sprout reach about 3/4 of the length of the grain,the germination process is interrupted.The grain,which is now referred to as green malt,is spread evenly on a floor and dried above a kiln-oven.The dry stops germination and eliminates bacteria and mould.The taste of the barley now assumes a malty note and a certain sweetness.If you add peat to the dry fire,the malt develops a smoky taste.The amount of peat is calculated in parts per million phenol.Lightly peated malt contains 2-10 parts per million,heavily peated malt 50-60 parts per million phenol .After curing,the barley has a water content of 4 to 5%.The traditional pagoda roof,a typical feature of distilleries in Scotland ensures optimal air flow to the kiln.Immediately before mashing,the malted barley is ground to grist,so that it opens and the sugar content can be extracted.
Then,in the mash tun,it is mixed with water at a temperature of 62 to 65 degrees celsius.The mash is strried constantly using a rotating rake.Now the beta amylases are activated and convert.the starch into various sugars,which are then dissolved in the water.Sugar types include maltose,glucose,maltotriose and dextrin.The conditions under which the enzyme works affect its activity.In order to shorten the processing time,the brewer ensures the best possible conditions in the mash.After 30 minutes,the liquid is drained through the perforated bottom of the mash tun and collected.The mash is mixed with water a second time,this time at 70to 75 degrees celsius.The liquid is drained off and collected.The mash is now heated for a third time with a water temperature of 80 degrees.However,the sugare content is much lower than in the previous steps,and therefore this mash is not used for the subsequent fermentation but it is cooled to 64 degrees celsius and used for the next step in the mashing process.The sugary liquid is cooled down to 16 to 20 degrees celsius and the resulting wort is pumped into the fermentation tank,the so called washback,where it is mixed with yeast.The yeast cells ferment the sugar into alcohol and carbon dioxide.The entire fermentation process takes up to 4 days.The beer-like wash has an alcohol content of 8 to 11% and can now be distilled for the first time.To initiate the distillation process,the wash is heated in the first copper still the "wash"still.Copper is the ideal material for this because it is excellent heat conductor and can also be easily formed.What's more,it eliminates unwanted sulphur compounds.
The pot-still consists of three parts:the kettle,the goose neck or lyne-arm and finally the cooler.The size and shape of the still has an influence on the taste of the whisky.Alcoholic vapors rise in the neck of the still,because alcohol evaporates at a lower temperature than water.The water is left in the still.In the shell-and-Tube heat exchanger,the alcohol vapours are cooled and condense again.The result is known as low wine,and has an alcohol content of 20 to 25%.The distillation process is now repeated in a second,small copper still,the so-called spirit still.This usually takes around 8 hours.In this step,the alcohol-and with it the majority of the flavourings and aromatic substances-is separated form the water,and concentrated,resulting in a fine distillant with an alcohol content of 65 to 70 percent by volume.This distillant is separated by the distiller in the spirit safe into foreshot,middle cut and feints.The foreshot contains residues from the previous burning process,(as well as volatile toxic methanol.The middle cut or heart flows through a meter which is later used to determine how much spirit tax should be levied.In the feints,fusel oils are extracted,as they have a negative effect on the taste and can even be harmful.Now the fine distillant is pumped into the spirit receiver.
The new make spirit is partially mixed with water and filled into oak barrels for final storage.After numerous trials and experiments,two types of wood have become the accepted standard material used for the storage and maturing of whisky,American white oak and European oak.Nowadays,whiskey barrels are made form Japanese oak.Years of aging in and oak barrel can account for 60-80 percent of the taste.Of course the ingredients in the raw whiskey,which is still very spicy after distillation,also give it its distinct flavour.However,it is only through storage that the whisky gets its final round and unique taste.By law,Scottish whisky must be matured in the barrel for at least 3 years.AS the wood breathes,between 1.5 and 2 percent of the liquid gold evaporates annually,which is called the Angels'Share.For the darker types of whisky,the distilleries prefer barrels in which sherry or port was previously stored.Used American bourbon barrels are used for lighter whiskies.Rum and Barolo barrels can also influence the taste of the whisky.The flavour and aroma is influenced not only by the wood of the barrel and the individual distillation process,but also by the surrounding climate and environment.Whiskies from the island of islay,for example,get their very individual barrels are regularly refurbished in individual character from the salty sea air.Used barrels are regularly refurbished in cooperages,so that the barrels are used several times over,some for decades.
Naturally a whisky will absorb less flavour if it is matured in,for instance,a sherry barrel that has been used several times before.Thus all these various factors intertwine over the years to create a distinctive whisky in each individual barrel.
