pepper-upper

or pep·per up·per

[ pep-er-uhp-er ]
/ ˈpɛp ərˈʌp ər /

noun Informal.

something, as a food, beverage, or pill, that provides a quick but temporary period of energy and alertness.
something added to food to relieve blandness.
an experience that increases enthusiasm or zeal, as a pep talk.

Origin of pepper-upper

1935–40; pep up + -er1, suffixed pleonastically to both v. and particle