You can get salt in Family Island for completing orders from the merchant and shaman. There may be some salt in the gifts that are given out for completing a chain of orders. You can use salt to cook food.
Note: you have a VERY small chance of getting salt for collecting starfishes.
![](https://d2duuy9yo5pldo.cloudfront.net/melsoft-games/c356aa2d-2401-4a09-9b22-fc73e196c3f2-2t.png)