By providing transparency, auditability, and traceability throughout the food supply chain.
Or in other words it prevents fraud via a tamper-proof system for data collection and monitoring. If the input data is falsified and people to get sick, it’s just a matter of plugging in the QR code for the contaminated product and within seconds you know the identity of the participant who authored the product and where it came from. The identities of all participants are already known before hand by the Membership Service Provider.
Think of it like as if someone signed a malicious commit with their GPG key containing their name and address but with additional tamper-proofing pushed to an immutable repo, it’s not going to be very hard to trace back and slap a fine on whoever is responsible; effectively greatly reducing the Oracle problem.