What are the functions of emulsifier in soft drinks?

The function of an emulsifier is to enable, and maintain, a uniform dispersion of oil droplets within the aqueous phase.

The small size of the droplets (1-2 um) means that the system tends to instability since the potential energy increases with total interfacial energy, which is the driving force of coalescence.

Emulsifiers are used to minimize the total interfacial energy and act by adsorbing at the oil-water interface in an oriented manner.

Concentrated emulsions are used to impart both cloud (neutral emulsion) and flavor (flavored emulsion) characteristics to the drink and are usually formulated to be used at a rate of about 0.1%.

The beverage emulsions diluted several hundred to several thousand times to provide flavor, color and a cloudy appearance for the beverage. A beverage emulsion must be stable in both the concentrate and diluted forms.

Brominated Vegetable Oil is an example of emulsifier and clouding agent used in soft drinks. It keeps flavor in oils in suspension and gives a cloudy appearance to citrus-flavored soft drinks.
What are the functions of emulsifier in soft drinks?

Food Additive: Acidulants

Food Additive: Acidulants
From the root word, acid, in acidulants, one can conclude that this class of compounds tends to lower pH of any food in which the compounds are incorporated. They also enhance desirable flavors, and in many cases, such as in pickled products, are the major taste component. Vinegar (acetic acid) is added to relishes, chili sauce, ketchup and condiments as a flavor component and to aid in the preservation of these products. Since the microbial spoilage of food is inhibited as the pH of a food is lowered, acidulants are used for that purpose in many cases. Many acidulants occur naturally in foods (e.g., citric acid in citrus fruits, malic acid in apples, acetic acid – the major component of vinegar). Tartaric acid is widely used to lend tartness and enhance flavor. Citric acid is widely used in carbonated soft drinks. Phosphoric acid is one of the very few inorganic acids used as an acidulants in foods. Citric acid accounts for 60% of all acidulants used in foods.

In addition to their preservative and flavor enhancing effects, acidulants are used to improve gelling properties and texture. Acidulants are also used as cleaners of dairy equipment.

Acidulants may be used in the manufacturer of processed cheese and cheese spread for the purpose of emulsifications as well as to provide a desirable tartness.

Acid salts may be added to soft drinks to provide a buffering action to prevent excess tartness. In some cases, acid salts are used to inhibit mold growth.
Food Additive: Acidulants