Holiday weekend or not, summertime means grilling time. A waft of burning hickory or charcoal from a smoky barbecue grill is enough to make anyone’s mouth water—though, curiously, the smoke itself isn’t something we can actually taste, as the receptors on human taste buds don’t respond to smoke, at least on their own. Taste is formed by texture, flavor, and scent combined, and, as sensory scientist Marcia Pelchat once explained to The Independent, “Most of the flavor of smoke is smell.” Because scent is processed through the limbic system, the sensation also persists in our long-term memory, which may explain why a smoky aroma can elicit more memories than the meal itself. And as any BBQ lover knows, the sweet, smoky scent is bound to linger and cling to every fiber of the shirt on your back.