Soft drinks are one of the most recognized parts of Western culture. Beginning as tonics for fatigue and anything else that might be the matter with a patient, they have evolved into sweet bubbly accompaniments to hamburgers and french fries and other widely recognized parts of Western culture.
Most soft drinks are characterized by carbonated water, sugar, and caffeine. Variations in soft drinks generally advertise either flavor differences, or the absence of one or more of the three main ingredients.
Colas were originally blends of extracts of the coca leaf and the cola nut, mixed with sugar water. The coca leaf is no longer used, but the cola nut remains in the recipes that are public, and reportedly is also still in the secret Coca-Cola recipe.
The cola nut comes from the Ivory Coast in Africa, primarily from two species of trees, Cola acuminata, and Cola nitida.
The main active ingredients in the cola nut are the alkaloids caffeine and theobromine ("food of the gods").
Colas stimulate digestive juices, and carbonated water speeds the digestion, and the combination of effects, along with the stimulant action of the two alkaloids, can make a difference to someone who is not feeling well.
The artificial sweetener aspartame is the low-calorie sweetener of choice at the time this is being written, having replaced cyclamates and saccharin as the favorites. The sweeteners neotame, acesulfame, and sucralose are sometimes used.
Acids are added to soft drinks for extra bite, and mouth feel. The primary acid used in colas is phosphoric acid, while the one used in citrus flavored drinks is usually citric acid.
Carbonated water (water that has the gas carbon dioxide dissolved in it under pressure) is also mildly acidic (it is chemically carbonic acid, H2CO3).
Caffeine is added as a stimulant, but it has a bitter taste that is a component in many soft drinks. is
Orange soda often contains glyceryl abietate, also known as "glycerol esters of wood rosin", and brominated vegetable oil. These help keep fatty flavors suspended in the liquid (density balancers and emulsifiers). Gums and modified food starches are also used for this purpose. Glyceryl abietate is also used in cosmetics, as the waxy substance in eyebrow pencils.
Sodium benzoate is used as a broad spectrum antimicrobial, inhibiting bacteria, molds, and yeasts. The high acid content of the soft drink is necessary for the preservative action. Sodium citrate buffers the acids, so the pH stays low (acidic). It also emulsifies any fats or fat-soluble compounds in the flavorings, keeping them in solution.
Potassium sorbate is added to inhibit yeasts and fungi.
Ascorbic acid (Vitamin C) is used as an anti-oxidant.
In colas, the color comes from caramel coloring (burnt sugar).
Red 40 and other colors are used in fruit flavored drinks such as orange soda.