Alanine is a non-essential amino acid with the formula C3H7NO2 that serves as a building block for proteins and plays key roles in metabolism. It participates in the glucose-alanine cycle, facilitating nitrogen transport from peripheral tissues to the liver for gluconeogenesis. The L-enantiomer is the biologically active form found in proteins, while the D-form occurs in bacterial cell walls. Alanine contributes to energy production via the citric acid cycle and supports immune function. In food applications, it acts as a flavor enhancer due to its sweet taste profile and is used in nutritional supplements and processed foods. Its polar yet small side chain allows high water solubility while remaining insoluble in lipids.