You should keep a supplier list as part of your SFBB documentation. This is found in the Records section of the document which can be accessed via the Process Documentation widget found in the Control Centre.
For your delivery checklists on the Memo you can populate the check with your supplier names via the What tab of the Configuration widget found in the Control Centre. There are templates available for Frozen, Chilled and Ambient deliveries with fields for supplier names ready for you to fill in. Copy, edit and add to these as you wish or create your own delivery checklist.
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