taster
noun
[ ˈteɪstə ]
• a person employed to test food or drink for quality by tasting it.
• "a tea taster"
• a small quantity or brief experience of something, intended as a sample.
• "the song is a taster for the band's new LP"
Origin:
late Middle English: in early use from Anglo-Norman French tastour, from Old French taster ‘to taste’; later from taste + -er1.