Salt can be ingested with many different kinds of food, improving the taste. Human can survive for quite a while without salt, but that is neither healthy nor enjoyable.
The survivor needs salt. Salt gives certain comestible more morale bonus. Salt can be a type of vitamin. The problem is that we need a good UI. Making a salted version for every recipe, or requiring the player to manually feed their character daily salt, is not reasonable.
How can we make salt play a role without it annoying us? I suggest that the player character checks for nearby salt when they eats, and then automatically takes a little bit with their food. Eating food with salt adds +1 to enjoyability. Prolonged lack of salt gives certain status effects.
Similarly, the player character checks for nearby soy sauce, black pepper, cinnamon, vinegar, chili powder, sugar, maple syrup, sugar beet syrup, mayonnaise, horse radish, mustard, ketchup, red sauce, blueberry jam, strawberry jam, garlic, lemon, etc when they eats, and then automatically takes a little bit with their food. Eating food with condiment adds +1 to enjoyability. A survivor with a well-stocked kitchen can get more than +10 bonus( it may need to be capped).
Thus, the various spice and condiment becomes more useful, when they can be automatically consumed and then benefit the survivor.