13.1 -INTRODUCTION TO DISTILLED ALCOHOLIC BEVERAGES (SPIRITS)

13.2 Steps of Distillation

13.3 Styles of Spirit
13.4 Types of Stills

13.1 Introduction

The process of distillation is used for making liquor of high alcoholic strength from liquors of lower alcoholic strength. The original Latin verb 'Distillaire' means "To trickle down" like raindrops or condensed steam on glass coffee spots.

During distillation, a base liquor containing alcohol is heated till alcohol becomes steam or vapor because alcohol boils at a lower temperature than water. It is possible to vaporize all the alcohol from the base liquor leaving mostly water behind.

The vapor is trapped and cooled so that it condenses back to a liquid stage. The resulting liquor has a higher concentration of alcohol. This process gives us a higher concentration of alcohol. Distillation sounds easy and so it is, if you are making industrial grade alcohol. However, producing a safe and good tasting alcoholic beverage is much more delicate and complex.

13.2 Steps of Distillation

Spirits are made in specially designed machine called 'Still'. As base liquid in the still warms up, the first vapor formed is of Methyl Alcohol. This type of alcohol is used in fuels & anti freeze agents. It is illegal as well as harmful for human consumption.

Modern distillation process first removes all the Methyl Alcohol. Ethyl alcohol- the alcohol in the spirit you drink begins to vaporize along with the water. The vaporized mixture is carefully collected by rapid condensation until the later stages of condensation, when it becomes more water than alcohol. Ideally distillers must redistill the base liquor at least once & sometimes twice or thrice.

Besides alcohol or water, base liquor contains many aromatic or flavoring substances called "Congeners". These add richness and complexity to a finished spirit. It is a challenge to distiller to capture them without including any undesirable impurity. If the a spirit is to have a neutral taste as in the case of Vodka & Gin, the condensed vapor called "Distillate" must be redistilled or rectified after collection. Rectification is simply a technical term for repeated distillation that removes all traces of flavorings from the spirits.

13.3 Styles of Spirit

To classify the varied spirits of the world, one should consider that whether the spirit has its own intrinsic flavour or it is a neutral spirit with added flavor from fermented juice of grape or any fruit. The basic wine has multitude of flavour. Many of which remain the spirit after distillation. In addition the young spirit is transferred to wooden cask for ageing & wood lend colour & flavour to the finished product. On the other hand Gin is made from the rectification & spirits can be distilled from a variety of waste material including grapes, potatoes & molasses. After rectification the gin has no flavour except for the taste of alcoholic content. At this stage distillers add herbs such as 'Junipers' or 'Coriander' to give gin its distinctive character.

13.4 Types of Stills

There two basic types of stills and they are as follows:

13.4.1 Pot Still

Fig. Pot Distillation

The pot still is the traditional tool of the distiller. Its basic design has changed a little since the days when the medieval monks distilled the spirits for the medicinal purposes, usually made up of copper in an onion shape. Even today the pot can be heated by a fire burning below. More often it is enriched by gas operating warming coil. The heated liquor inside the still vaporizes & passes through a condenser where the spirit is liquefied & collected. The process is slow as only small quantities are made at a time in each pot still. Today pot stills are used for high priced spirits known for their special rich flavors. This includes Malt Whiskies from Scotland, Cognac from France, Irish whiskies & most dark rums. They may also be used for the rectification in making Gins or other white spirits.

13.4.2 Patent Still

It is also known as continuous still or coffee still after Aneas Coffey, an Irish man, who invented it. It can be used continuously day & night without constant attention as required by pot still. Steady stream of liquor enters the still at the top of the copper column where it is heated to steam and vaporized. The distillate then passes through condensing pipes.

In another column, it is vaporized by steam and rectified. Specially designed plates inside the column ensure that the correct amount of drinkable elements is collected.The advantages of this system are many- large quantities of spirits are produced at a relatively lower cost. In addition, the patent still is more successful of purifying alcohol than the pot still. Modern drinkers prefer light type of drink- a specialty of the patent still.

The patent still consists of 2 columns each about 18 meters high. One column is called the analyzer, whose role is to separate the constituent parts. The other column is rectifier which raises the strength of spirit and also purifies it and condenses the alcoholic vapors. Each column is sub-divided horizontally into chambers by perforated copper plates which have a drip pipe leading to the chamber underneath. Both columns are preheated by steam and the fermented liquid or wash enters at the top of the rectifier and gradually descends through it inside a pipe.

By the time the wash reaches the bottom of the rectifier, it is almost at the boiling point. It is then pumped into the analyzer where it gradually makes its way downwards through perforated plates and bubble caps. As it descends, it is met by a current of raw steam which has been injected under pressure into the bottom of the analyzer. On contact, the steam boils the wash and produces alcoholic vapors. These vapors rise and are channeled by a pipe into the bottom of the rectifier. The spent wash is removed at the bottom of the analyzer.

Meanwhile inside the rectifier, the alcoholic vapors pass through a series of perforated plates. As they rise, at certain points they meet the cold wash being carried down the rectifier by the wash coil. Partial condensation takes place-the vapors getting cooler and the wash, on its way to analyzer, getting hotter. When the spirit vapors reach two third of the way up in the rectifier, they hit a cold spiral plate or water frame and precipitate. The first liquid to emerge- the Heads or Foreshots- is removed and sent back to the analyzer because it is pungent and needs further refining. The comparative pure spirit which follows is guided into a spirit receiver. This will be deionized water and matured for a short time before being treated (or flavored as in case of gin) according to style.

Introduction to Distilled Beverages

Beverages Service
Paperback
January 2020 Edition
Author:
Dr. Deepa Prasad Venkatraman
Ulhas Chaudhari

Food & Beverage Services Practical & Techniques
Paperback
January 2020 Edition
Author:
Dr. Deepa Prasad Venkatraman
Ulhas Chaudhari