Thanks for your question. This is Ethereum contract.
In order to prevent false reviews, we have a peer-review system in which users can check the validity of the post based on criteria like the existence of the restaurant, the address of the restaurant, whether the dish exists on the menu, etc. Once the post is validated, it will be posted on the blockchain and the poster will get tokens for successfully submitting a valid post. Also, to encourage quality content, users, whose posts receive the most likes and "pins" in a payment period, will be rewarded with extra MUN tokens. That way, not only users are rewarded for submitting valid content, they are also rewarded for contributing QUALITY content; content that the community finds useful.

You can find more details regarding how to prevent false and fake reviews on page 12 in our white paper at https://s3.amazonaws.com/munchee-docs/Munchee+White+Paper.pdf. Thanks!