Product Conditions and Minimizing Do2 Pickup

Control of DO during packaging is a fundamental component of quality canning but the management of DO is not isolated to the packaging process. Best practices on the cellaring and production side should be able to mitigate any O2 pickup from production and transfers, and be able to deliver a product with relatively low starting numbers in tank on canning day. Accurate product preparation regarding temp and carb greatly helps optimize our fills and minimize pick-up during filling.

Here are some areas to focus on in the cellar to ensure low DO before packaging:

• When transferring from the tank be sure tanks, hoses, and pumps have been adequately sparged.
• Any time ingredients are added post-fermentation, such as hops. sugar or other adjunct additions, precautions should be taken to remove O2 from the ingredient or method of introduction.
• Make up water or Batching water for a formulated product should be de-aerated before use

Excess Oxygen trapped into a can along with product will cause the liquid to oxidize. Depending on the product profile there effect on the liquid could be minimal, but it can extend to degradation of the color and sensory of the product, or in extreme cases, trigger corrosion events and leaking inventory.

IHC canning tech’s have been instructed on a variety of filling techniques to prevent and reduce O2 pickup during the filling process. When it comes to carbonated products, much of our methodology in our approach stems from the conditions of the liquid we are filling. We will often use the term “cap on foam” to describe the product conditions we wish to see on filled cans.

• By controlling fill speeds an operator will attempt get a product to fill to its ideal weight range, while simultaneously encouraging a limited amount of Co2 to release from solution and into the headspace of the can.
• The filler is timed so that as this breakout is occurring, it is forming a convex cap of foam over the mouth of the can, therefore purging much of the atmosphere and O2 from the headspace.
• The lid is then quickly seated onto the can, while this cap of foam is still present, essentially trapping the Co2 gas out into the can as it’s being sealed.

For all this to happen successfully, product conditions should be carefully monitored and adjusted prior to canning. Proper tank specs are a delicate balance between temperature and Co2 pressure. Too cold of product or too low of Co2 volumes, will fail to generate the Co2 breakout needed to purge the headspace in the time needed. Inversely, warm product conditions, or high Co2 volumes will cause excessive breakout and an inability to control fill volumes. Each style of product will require slightly different specs to achieve this, depending on the characteristics of the beverage and the amount of sugars, and proteins present. Local Iron Heart Managers would be happy to discus specifics in regards to your product.