Ethyl (S)-3-hydroxybutanoate, also known as (S)-乳酸乙酯, is an ester formed by the condensation of ethanol and (S)-3-羟基丁酸. It is commonly used as a flavoring and fragrance agent in the food and cosmetics industries due to its fruity and sweet aroma and taste. Additionally, its potential use as a starting material for synthesizing various organic compounds, including pharmaceuticals and agrochemicals, has been investigated.