How Long will by Cold Brew Stay Good?

Some cold brew coffee drinkers, really love it, but don’t drink all that much due to caffeine or other reasons.  But we all want it to taste great and all have tasted stale, oxidized, or even sour flavors in old coffee.  How can one maximize the life of the coffee and then how long will it last?

Normal still cold brew coffee will stay good longer than hot coffee which has cooled.  Oxidation occurs much more readily in hot water than in cold.  Hot coffee has more acids and tannins in it than cold brew.  They start to degrade shortly after the coffee is made, and often the coffee has noticeable oxidation in a short as a half hour.  The oils in coffee solubles can oxidize more quickly at elevated temperatures, causing coffee to taste sour. Acids also degrade, the most notable of which is chlorogenic acid into quinic and caffeic acid, causing coffee to taste bitter. (1)

Cold brew also will oxidize, but it takes much longer.  Even in a cup, it will still be drinkable the next day if kept in the refrigerator.  If you keep it in a sealed container like a jar, bottle, or growler, you should be able to get two to three days before you notice a taste change.  If the cold brew is concentrated and you dilute it at the time of serving, you will get a week out of it.

The real “shelf-life” lengthener is Nitrogen.  Food distributors have known that for a long time.  Lettuce is harvested in the Salinas Valley of California, put into refrigerated containers, filled with Nitrogen, and sealed in the late Spring and Summer.  That same lettuce is then shipped to Japan and Europe and the containers are opened up the next winter.

Even the simple act of using a disposable Nitrogen wine preserving can will double your shelf life to two weeks at least.  Those who make Nitro cold brew or even just keep their coffee under Nitrogen should get at least a month out of their coffee if kept cold.  I’ve found that cold brewed Nitro coffees don’t even reach their peak flavor for at least 24 hours after they’re put into kegs.  And it’s not just the Nitrogenating part.

We’ve tried kegs of cold brew that were a month old, and couldn’t tell a difference from when they were freshly made.  But in order to do that, one has to minimize oxygen exposure every part of the way.  We put a small layer of Argon on top of our brewing vessel.  And we make sure our keg is purged with Nitrogen before adding the coffee.  Coffee Love in Los Angeles even Nitrogenates their brewing water and tries to drive out much of the free Oxygen in the water.

For those roasters who can, make sure the canning line fills the cans completely and that you microdose the coffee with liquid Nitrogen just before the lid goes on.  Of course you have to observe all local and USDA health department rules.  But often the listed shelf life is two to three months if the coffee is kept cold.  I once opened a can of Los Angeles’s B Sweet Nitro Cold Brew, it still was tasty at 15 months old.