4-Mercapto-4-methyl-2-pentanone is a highly potent organosulfur compound used as a key ingredient in flavors and fragrances. It exhibits an intense, diffusive aroma with prominent sulfurous, blackcurrant (cassis), and tropical fruit notes, accompanied by green, fruity, and subtle meaty or roasted undertones. In the food industry, it is widely employed to recreate authentic blackcurrant, passionfruit, and other exotic fruit flavors in beverages, confectionery, snacks, and processed foods. In perfumery, it is valued for mimicking the natural scent of blackcurrant buds and is incorporated into fine fragrances, particularly in fruity, chypre, and oriental compositions. Its extremely low odor threshold allows usage in trace concentrations, often in combination with other sulfur compounds to develop complex fruity or savory profiles in both liquid and dry applications.