I utilized a Quality plan when I was working in the bakery industry and I found that it helped to reduce food waste and it assisted the operators with understanding the adjustments they would need to make on their equipment based on what they were seeing during quality checks and when to escalate an issue. While many food companies do not fully utilize a quality plan because it is not a regulatory requirement, I think its the missing link to any successful management system.
Just like a HACCP or Food safety plan, a quality plan is a predictive system, preparing your for the known and foreseeable quality threats. I have worked many places where they collect quality data but then they do not really do anything with that data. The plan will make those checks meaningful.
I like using the Fishbone diagram approach for determining quality threats. BRCG has a good guidance here. https://images.templ...se-Analysis.pdf It discusses more root cause analysis but the same concept can be used for understanding how your product quality may be impacted at each processing step.