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.
The largest segment of the soft drink industry is the colas.
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
The main active ingredients in the cola nut are the alkaloids
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.
Sugar has been largely replaced by
high fructose corn syrup,
largely because the latter is not price controlled, and is a
little bit sweeter, so less is needed.
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,
sucralose are sometimes used.
Acids are added to soft drinks for extra bite, and mouth feel.
The primary acid used in colas is
while the one used in citrus flavored drinks is usually
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.
Orange soda often contains
glyceryl abietate, also known as "glycerol esters of wood rosin",
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
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.