We make a famous hot sauce, but we are having a problem properly sealing the bottles for shipping. We tried to shipped the sauce to friends and family, but after a 3 to 4 day trip, the sauce gets to them and explodes, with half the sauce bursting out as soon as bottle is open. Any advice on how to keep my hot sauce from expanding during travel and exploding out of the bottle?
The sauce is fermenting.
Fermenting things give off CO2. That might not be bad for a hot sauce. But as long as it is going on the flavor is going to be changing. Also as regards exploding, Co2 in a sealed space will build up pressure.
You can kill your hot sauce before you seal the bottle. I would can them in a hot water bath - traditional canning. Then they will stop fermenting. They will be safe to seal up and ship.