21 OCTOBER 2019
At WilCraft Can, we have heard stories about how other mobile canners completely fill the can with liquid, then they use the can end to push out the overflow. At WilCraft Can we know this should never be done in any liquid product, especially those liquids that are pressurized. Based on all our experience filling pressurized products, we know how critical having headspace is. In fact, the beverage cans are designed to have headspace in them. You may be wondering why a picture of bottles instead of cans. So you can see how all liquid products use headspace, and since we can't see through cans we get to show the importance of headspace with bottles.
12 oz beverage cans have 375 mL of total volume and the label claim is for 355 mL. The can manufacturers designed this extra 20 mL in the can for headspace above the liquid. Beverage cans should have 3-5% headspace for expansion so cans do not buckle. If your mobile canner is capping on liquid they don't understand pressurized packaging and they are putting you at risk for buckling or exploding cans when the liquid in the sealed can expands at elevated temperatures or when the carbon dioxide comes out of solution and has no where to go.
The link below from Brewing Industry Guide discusses the importance of headspace in the can:
We selected our Codi Canning line since it makes it extremely easy to insure we have headspace in our cans. By controlling our pressure differential and the throttle we can get very specific control of our product fill weights to make sure we have the right amount of headspace. Then we make sure to cap on foam to keep the total packaged oxygen in the can nice and low.
Call WilCraft Can to find out more about how we are truly a different mobile canner.