How is data entry in private and consortium blockchains trusted

Suppose we have a consortium blockchain like Food Trust IBM for supply chain. How can we be sure that the data entered to the blockchain by different parties is trusted. I mean, some companies may say that its fruits are grown organically, while it is not true. Or some other company might say that it received something on Monday, while the truth is it received it on Sunday. Does the blockchain itself have an algorithm to prevent these kinds of issues, or there must be some other solution like using IoT sensors?