You could do it with contracts & law. Offer 10 year salaries-index-linked-at-a-minimum employment contracts. Employment contracts that specifically state the employer won't do things like outsource, (or if you're in USA won't do 'at will'). Employment contract that'll give 5 times the legal minimum of redundancy leave. Require that upper level management/directors don't get bonuses if there's been any pay freezes or pay cuts. Lots and lots of little things like that might be a way.
This will (obviously) restrict the business, and limit its resaleability. ("Come buy us out, you just have to pay 50 people for the next 8 years").