Bitters
A bitters is an alcoholic beverage flavoured with herbal essences and has a bitter or bittersweet flavour. Numerous brands of bitters were formerly marketed as patent medicines, but are now considered to be digestives, rather than medicines. They commonly have an alcoholic strength of 45% ABV and are used as digestives and as flavouring in cocktails.







 
Angostura Bitters 

ALC/VOL = 45.6% Alcohol
A concentrated bitters made of water, alcohol, gentian root, and vegetable flavouring extracts. Produced in Trinidad and Tobago, the recipe was developed as a tonic by German Dr. Johann Gottlieb Benjamin Siegert, a Surgeon General in Simon Bolivar's army in Venezuela, who began to sell it in 1824. Angostura bitters are alleged to have restorative properties. It is the major flavour ingredient in "Lemon Lime and Bitters".
Creole Bitters 

ALC/VOL = 39% Alcohol
Creole Bitters are reminiscent of a style of bitters dating back to an era before cocktails even existed. Back then, bitters were made by doctors and apothecaries, primarily for the use in liquid tonics and then eventually as an ingredient in alcoholic beverages. Bitter, sweet and spicy. According to the traditional Creole style, fruity and floral aromas unite with the flavours of anise, caraway and fennel.
Orange Bitters 
 

ALC/VOL = 45% Alcohol
Orange bitters is a cocktail flavouring made from the peels of Seville oranges, cardamom, caraway seed, coriander and burnt sugar in an alcohol base. Fee Brothers of New York has been producing orange bitters for many years, but distribution was limited. Mixologist Gary Regan created an orange bitters in the 1990s to fulfil his needs for a "decent bottling of orange bitters". There are now a number of different brands on the market. There is also an Angostura Orange Bitters.
Peychaud's Bitters 

ALC/VOL = 35% Alcohol
Originally created around 1830 by Antoine Amédée Peychaud, a Creole apothecary from the French colony of Saint-Domingue, now Haiti, who settled in New Orleans, Louisiana, in 1795, is distributed by Sazerac. It is a gentian-based bitters, comparable to Angostura bitters, but with a lighter body, sweeter taste and more floral aroma. Peychaud's Bitters is an important component of the Sazerac cocktail.It is produced by the Buffalo Trace Distiller of Frankfort, Kentucky.
Whiskey Barrel Aged Bitters 

ALC/VOL = 17.5% Alcohol
Freshly emptied oak whiskey barrels from Tennessee, interiors charred and soaked with aged whiskey, are used by Fee Brothers to age this aromatic bitters. Savour the result of the mingling of these great flavours. This premium bitters is a strictly limited edition item and Fee Brothers bottle it only once a year in the spring. When it's gone it's gone (until next year anyway.)
Cranberry Bitters 

ALC/VOL = 17.5% Alcohol
Adding a tart sweetness to your favourite drinks, Cranberry Cocktail Bitters is new. One of the companies to produce this unique product is "Fee Brothers" in Rochester N.Y. Bitters is to cocktails as vanilla extract is to baked goods; you can improve dimension and overall flavour with just a touch, but without it, you’ll find the end result lacking. Try it in a Cosmopolitan Cocktail.
Peach Bitters
ALC/VOL = 19.5% Alcohol
Peach Bitters are a contemporary interpretation of a classic style of bitters. Fresh and fruity with a delicate peach nose, balanced with hints of almonds and backed up with spices and balanced bitter nuances. The natural aroma of fresh peaches dominates while it is completed by fresh citrus and unobtrusive spice flavors.Goes well in  Bellini cocktail, and aged spirits such as cognac and bourbon whiskey.
One of the companies to produce this unique product is "Fee Brothers" in Rochester N.Y.

Underberg 

ALC/VOL = 44% Alcohol
Is a digestive bitter produced in Germany, made of aromatic herbs from 43 countries. It is based on a secret and proprietary recipe, guarded by the Underberg family since the company was founded by Hubert Underberg-Albrecht in 1846. The herbs are distilled and the extracts are then matured for many months in barrels made of Slovenian oak.
Campari Bitters 

ALC/VOL = 25% Alcohol
An alcoholic apéritif obtained from the infusion of herbs and fruit (including chinotto and cascarilla) in alcohol and water. It is a bitter characterized by its dark red color. Campari is often used in cocktails and is commonly served with soda water, wine, or citrus juice. It is produced by the Campari Group, based in Italy. The history of Campari began in 1860 with its invention by Gaspare Campari in Novara, Italy. Unlike the more concentrated bitters, Campari is served as a normal 30ml measure.
Fernet Branca 

ALC/VOL = 45% Alcohol
A bitter, aromatic spirit, it is made from a number of herbs and spices which include myrrh, rhubarb, chamomile, cardamom, aloe, and saffron, with a base of grape distilled spirits, and coloured with caramel. Usually served as a digestive after a meal but may also be served with coffee. A mint-flavoured version of Fernet is also available. Because of its list of ingredients, a number of home remedies call for Fernet, including for the treatment of hangover. Fernet is served as a normal 30ml measures..