I oftentimes ship a sauce only sold in my area to family at different elevations. The problem is that the bottle it’s sold in isn’t very secure and many times it’ll break in transit and leak everywhere.
What should I look for when shopping for bottles/containers to use for shipping?
Why not just replace it with a cap that isn’t a flip-top? Screw it on tight, squeeze the bottle slightly before putting the cap on so there’s a slight negative pressure. That would be my first thing to try.