Our original transaction endorsement policy required a member of each of the 4 organizations to endorse (sign) a chaincode invocation transaction. Now that we have added a new organization, we must update that policy to require a signature from a member of each of the 5 organizations. In the middleware folder, this new policy is defined in constants.js as follows:

var FIVE_ORG_MEMBERS_AND_ADMIN = [{ 
  role: { 
    name: 'member', 
    mspId: 'ExporterOrgMSP' 
  } 
}, { 
  role: { 
    name: 'member', 
    mspId: 'ExportingEntityOrgMSP' 
  } 
}, { 
  role: { 
    name: 'member', 
    mspId: 'ImporterOrgMSP' 
  } 
}, { 
  role: { 
    name: 'member', 
    mspId: 'CarrierOrgMSP' 
  } 
}, { 
  role: { 
    name: 'member', 
    mspId: 'RegulatorOrgMSP' 
  } 
}, { 
  role: { 
    name: 'admin', 
    mspId: 'TradeOrdererMSP' 
  } 
}]; 

var ALL_FIVE_ORG_MEMBERS = { 
  identities: FIVE_ORG_MEMBERS_AND_ADMIN, 
  policy: { 
    '5-of': [{ 'signed-by': 0 }, { 'signed-by': 1 }, { 'signed-by': 2 }, { 'signed-by': 3 }, { 'signed-by': 4 }] 
  } 
}; 

To switch the endorsement policy in our middleware, we just need to change the value of the TRANSACTION_ENDORSEMENT_POLICY variable in constants.js from ALL_FOUR_ORG_MEMBERS to ALL_FIVE_ORG_MEMBERS.