Taste And Smell

One of the basic rules of taste testing
is that testers shouldn’t wear perfumes or any other scent.  

Why? 
Because people can only detect 5 taste sensations
(sweet, sour, bitter, salty and umami)
through their tongues. 
All other “tastes” are due to smell.  

A bad smell will make a product taste bad.  
A floral scented room will give a wine a floral taste. 
And since smell is so important,
testers have to be able to smell the product itself 
(even in soft drinks,
smell is a factor in the purchase decision).