Paprika is the most popular cloud based ipad app, last I checked. Which was a while back. I don't know how easy it is to share recipes across multiple accounts/logins. You'd have to buy a license for every device, including your desktop where you'll likely be entering the content.
Evernote would work just fine as well and it would be my preference. It has good collaboration tools so you could even use mulitple accounts, which will become important in a minute.
Evernote is free for two device installs on the same account. But, it's easy to share content with other accounts, even on the free service.
I'd set it up like this.
Install desktop software where you already have your recipes. This is free. You have one other free app install for this account. i'd probably put it on your personal device, not a corporate ipad station.
Each ipad station will have it's own evernote account, one you will create for each device. You'll need separate email addresses for each of these devices. Any of the free email account services will be fine. This will also be advantageous for each ipad to have for its itunes account anyway. Keep a record of which device has which email and their passwords. This is a valuable record, so keep it safe and secure. You should permanently mark each ipad for theft and general security anyway and this same marker will be how you identify the ipad and its accounts.
Create a notebook in your "master' evernote account. You can copy and paste content into each recipe Note. in the notebook. You even incorporate Office documents or PDFs if you prefer. Share the notebook with each ipad account, via their evernote email login. Now the notebook of recipes and whatever else is available at each of those ipads. You can include prep notes, cleaning checklists and whatever else.
If you wanted, you could create a "stack" of notebooks. Each notebook in the stack could be organized by station and contain recipes and instructions for that station. You could then share the whole stack, where it's simpler at the station to find the information for just their station in their specific notebook.
You can also access evernote via the web and login to your content. This doesn't count as in installed device.
I like evernote enough that I pay for their premium service even though I don't use it to that ffull extent. I want to support the company and keep the service afloat. Google Keep or Microsoft OneNote are similar free apps. If you prefer those for whatever reason, the same ideas should transfer there as well.
Evernote will offer encryption by the end of this month if you're worried about your content being hacked.
You might want to lock down the ipads to a degree. Require the password to be entered for using itunes so they can't install apps. Same for email on each device Don't give your workers this password. Removee the web browser so they can't access entertainment or email sites and share your content away. I'm certtain there are more options available to corporate lock down an ipad, but I don't know the qpple world to give you better advice.