Possible Clues:

• Umami detectors
• They may be excited by dinner
• They perform sensationally in oral assessments
• They're on the tip of your tongue
• Dreadful dust beats creating sensational organs
• With them you relish acceptable risks, backing in small amounts
• They are on the tip of your tongue
• Parts of body designed to receive smacks
• They help distinguish the beginnings of 17-, 32-, 38- and 44-Across
• Wherein response is, in a sense, at the tip of one's tongue