Hampton Creek, a prominent start-up that is trying to bring tech industry panache to the world of mayonnaise, ranch dressing and other food products, has come under scrutiny by regulators for its business practices.

The Securities and Exchange Commission has opened a preliminary inquiry into Hampton Creek, according to a person briefed on the situation who asked not to be named because it had not been announced publicly.

The S.E.C. inquiry is a response to a recent report from Bloomberg News that described an organized effort by Hampton Creek to buy large quantities of its Just Mayo product — a mayonnaise that uses a plant-based ingredient instead of eggs — by sending undercover contractors into stores.

Kevin J. Callahan, a spokesman for the S.E.C., declined to comment. Bloomberg earlier reported the S.E.C. inquiry. Hampton Creek’s chief executive, Joshua Tetrick, said he had heard from the S.E.C. about the informal inquiry but declined to give further details.