L-Cysteine is a semi-essential amino acid containing a thiol (sulfhydryl) functional group that makes it uniquely reactive among the standard amino acids. It is naturally found in high-protein foods such as poultry, eggs, dairy, and garlic. In the food industry, L-Cysteine is extensively used as a dough conditioner in baking, where it reduces disulfide bonds in gluten to improve dough handling and extensibility.
Modern food-grade L-Cysteine is predominantly produced through microbial fermentation. It replaces earlier methods that used animal-derived sources. Its role as a flavor precursor in Maillard reactions also makes it valuable in savory flavoring and processed meat applications.
