The solubility of aspartame in water is dependent on pH and temperature, the maximum solubility is reached at pH 2.2 (20 mg/mL at 25oC) and the minimum solubility at pH 5.2 (pHi) is 13.5 mg/mL at 25oC.
Flavoring agent sweeter than sugar, metabolized as phenylalanine and aspartic acid. [PubChem]
Indication
Used as a diet supplement and sugar substitute.
Pharmacology
Aspartame (L-alpha-aspartyl-L-phenylalanine methyl ester) is a low-calorie sweetener used to sweeten a wide variety of low- and reduced-calorie foods and beverages, including low-calorie tabletop sweeteners. Aspartame is composed of two amino acids, aspartic acid and phenylalanine, as the methyl ester. Aspartic acid and phenylalanine are also found naturally in protein containing foods, including meats, grains and dairy products. Methyl esters are also found naturally in many foods such as fruits and vegetable and their juices. Upon digestion, aspartame breaks down into three components (aspartic acid, phenylalanine and methanol), which are then absorbed into the blood and used in normal body processes. Neither aspartame nor its components accumulates in the body. These components are used in the body in the same ways as when they are derived from common foods.
Toxicity
Mild gastrointestinal side effects including diarrhea have been reported.
Affected Organisms
Humans and other mammals
Biotransformation
Approximately 10% of aspartame (by weight) is broken down into methanol in the small intestine. Most of the methanol is absorbed and quickly converted into formaldehyde. Approximately 50% of aspartame (by weight) is broken down into phenylalanine. Approximately 40% of aspartame (by mass) is broken down into aspartic acid.
Absorption
Absorbed in the small intestine, aspartame is metabolized and absorbed very quickly.
Half Life
At room temperature, aspartame is most stable at pH 4.3, where its half-life is nearly 300 days. At pH 7 however, its half-life is only a few days.
