Okay, this is a common complaint and the most typically underlying cause is tonsil stones lodged in the crevices of the palatine tonsil tissue. When turning the head, compression of the tissues causes an expression of the sulfurous by-product caused by bacteria and can be activated on the taste buds or by virtue of the fact that it produces odor. Realize that the ability to taste requires the olfactory sense to be intact, or in other words you can taste the sulfur because it produces an odor.
A visit to your local dentist or doctor can palpate the affected tonsil region to discover and dislodge the stones.
Best regards,
Rutheford Rane, MD (ret.)