The selling environment has been tough in recent years for most packaged foods companies, and J.M. Smucker's (NYSE: SJM) latest operating results showed it isn't immune to the wider challenges its segment faces. On Thursday, the owner of Jif, Crisco, and other popular consumer brands posted flat sales to end its fiscal 2018, with profits coming in below management's targets.Executives issued a conservative outlook for fiscal 2019, which began May 1, that suggests its struggles will continue for at least another year.