Tod osier
WKR
That's helpful. You may be right. I think the binding agent is an issue that missing.
For most sausages, nothing additional is needed to get a good bind, it is the proteins in the meat, itself. One common problem that leads to a poor bind is over mixing when the batch is too warm and the fat melts and smears all over the protein (called breaking and ends up with a mealy and crumbly sausage). The ground meat should be super cold (not fully frozen) and when mixed, it should get stringy and sticky - that is the bind and it is ready to stuff.