Use 'unsavoury' to describe food or smells that make you feel disgusted or sick. The unsavoury aroma from the trash can made me gag.
Pro Tip 2/3
Intensity Varies
'Unsavoury' can range from slightly unpleasant to extremely offensive, depending on what you're describing. The soup had a slightly unsavoury taste, like it was starting to spoil.
Pro Tip 3/3
Physical Reaction
People often use 'unsavoury' when something affects them physically, like bad taste causing a grimace. He made a face at the unsavoury smell coming from the fridge.