Measuring Internal Product Temperature without Destroying Packaging

I work at company that bottles mainly citrus juice. We are currently pointing infrared thermometers on the outside of the container, but is this sufficient?

We do not want to have to throw away one gallon bottle of juice each load to check a product temperature.

We do not want to open bulk product (drums and totes) after we have sealed them. 

I was looking for other's opinions on how check the product temperature at shipping without compromising the packaging to comply with the SQF requirement to record core product temperature at regular intervals during loading. 

If you can get to the center of the pallet you can use a temperature recording thermometer that is a box.  You turn it on and set it in the pallet then when you go to ship it you recover it and connect it to a computer and you can get a temperature chart.  It's better than hitting the outside with an IR thermometer.

Is In-line temperature monitoring during filling not enough?  eg, if you have a max temp of 5 deg C and you fill at 3 deg C and the filling temp is monitored and recorded, and that happens in controlled temp room, AND you validate via trials your temps do not go up by eg 1 deg C, is that not enough? 

That is the type of process I typically see when filling large containers with product (eg juice, tomato paste, fruit pastes).

IR temp gun is not acceptable due to inaccuracy issues.