# How to measure the temperature of liquid in sealed container

• Pyotr

#### Pyotr

I am not a scientist or particularly good with math or formulas. I have been curious about this for a while, and would appreciate anyone clarifying/correcting me.

I have a stainless steel container that can be heated up to 75 degrees celcius/165 degrees Fahrenheit in a bain marie. It can hold one liter of liquid (that is the maximum fill line) although I have not measured the total volume of the container. I can get that later today.

I am aware that heating a sealed container with a mix of liquid and air, and perhaps if it is 100% liquid or 100% air, will explode if done at a high enough temperature. I would like to avoid this. :)

My understanding is that when you heat a sealed container, for the sake of the argument let's say it's 50% water and 50% gas, that the pressure increases. I am also under the impression that as the pressure increases, the temperature of the liquid and gas within the canister increases as well.

What I want to know is this: If I put this canister in a bain marie at a consistent 165 degrees, what is the temperature within the container over time? I'm assuming that as the pressure builds within the container, the temperature is going up, so even if the outside of the container and the water in the bain marie is a consistent 165 degrees, the temperature within is going higher and higher with the pressure.

To explain the practical purpose of this, I'm trying to make flavored vodkas with rasberries, strawberries, etc. I'd like to be able to heat the vodka and fruit in the sealed container to something like 225 or 250 degrees Fahrenheit for a set time, without exceeding the external temperature of 165 degrees. The problem is I have no idea what the internal temperature is. I can adjust the balance of liquid and gas within the container up or down, to whatever is optimal.

Any help is appreciated - and if any of my assumptions/facts are wrong I apologize.

If I put this canister in a bain marie at a consistent 165 degrees, what is the temperature within the container over time?
165 degrees F exactly. That is the equilibrium temperature, and if you start lower it will never go above that.
I am also under the impression that as the pressure increases, the temperature of the liquid and gas within the canister increases as well.
This is only an additional effect if you increase the pressure by reducing the volume, otherwise it is taken into account already.

so what temperature will it reach?

so what temperature will it reach?
165F exactly.

You're describing something circular/backwards: you are raising the pressure by raising the temperature, which is not the same as raising the temperature by raising the pressure.