δ-Decalactone (DDL) is a chemical compound, classified as a lactone, that naturally occurs in fruit[1] and milk products[2] in traces.

It can be obtained from both chemical and biological sources.

[6] DDL has applications in food,[7] polymer,[8] and agricultural[9] industries to formulate important products.

The S-enantiomer has a nutty odor with a fruity undertone.

[10] The R-enantiomer is the main component of the warning stench of the North American porcupine.