Still, get a meter! Strips are crap.
Your sauce will tint the test strip PLUS it is not highly accurate. The colors are already close. No way I would use any for sharing my recipes.
If your electrode was stored dry for years, it is toast. There's plenty of decent meters out there for this as a hobby.
To keep this from going in circles I would just say I recommend a meter. Strips are a ballpark measurement for your own use/recipe tinkering. Best of luck!