I thought I knew what caused a (1) gallon glass container of maple syrup to explore last June but a friend is convinced it was another cause. Here's what happened.
Last June I bought (2) gallons of maple syrup in glass containers. One I immediately put in the refrigerator and started using and the other in an entrance closet on the tile floor. I noticed that both gallons were filled right to the top with no air space but didn't realize what that could mean.
A few weeks later with the ambience temperature in the house at 78 degrees F, we heard an explosion and checked the closet. The gallon glass container had exploded into many pieces and much of the syrup was on the floor.
I have been thinking that the syrup was cold-packed at a temperature lower than 78 degrees F and that the 78 degrees F temp on the floor of our closet was enough to cause the syrup to expand and cause the explosion. A friend believes that this temperature change would not have caused the syrup to explode and that the syrup was likely NOT boiled down enough and continued to "ferment" causing it to expand in the glass gallon container I received it in.
I would appreciate thoughts on whether temperature changes and/or continued fermentation or some other reason explains the explosion.