Although new to the sport, I am finding that I like snuff quite a bit and have begun ordering larger quantities of a few blends that I really cotton to. As a pipe smoker, I am familiar with storing tobacco in Mason jars. My technique for pipe tobacco cellaring to ensure a positive seal on jars is to fill with tobacco (leaving a little headspace at the top), popping the jars into a preheated oven for 5 minutes (425* F/215* C), removing the heated jars and screwing on the lids. I've found this a foolproof way to ensure a good seal as the lids are sucked down, creating a vacuum as the jars (and tobacco) cool.
What is your method for producing a good seal on Mason jars of snuff? My assumption is the exposure to heat may be more detrimental to snuffs than pipe tobacco as most pipe tobacco is quite moist, so it can weather the 5 minutes at high temp to no ill effect. Do you just screw the lid on at room temp, store and eventually the tobacco eats up the oxygen inside, creating a pressure differential that pulls the lid down, or are you using heat treatment (whether oven, hot water bath, etc)?
Thanks for your help.