Tips: Storing green coffee at home

I have coffee I bought a year ago from Coffee Snobs in Australia. I recently noticed the flavour had rapidly diminished since when I first bought it. I thought: Is there a better way than storing it in burlap/cotton bags in my kitchen?

  How I’ve been storing coffee. It doesn’t get less scientific than this.

 How I’ve been storing coffee. It doesn’t get less scientific than this.

Short answer: Yes. There’s a better way. 

What to control for 

  • Keep humidity between 50-70%. Coffee responds dramatically to small changes in humidity. On average, coffee leaves the mill with a 12% moisture content; it should be roasted at that level. Coffee that has absorbed moisture even just up to 13% can be ‘bleached out’ and have muted flavour (as I experienced). There’s no agreed ‘perfect’ level of humidity, though various sources (blogs, suppliers) agree a range of 50-70% humidity would be appropriate. 
  • Keep temperature between 5 and 20 degrees C (40 - 70 F). Temperature level is important, as is stability. So is ventilation and insulation (to avoid temperature shocks). Freezing is not a solution - some storage experts say if coffee freezes it has a dehydrating effect and results in a less intense cup with less edge! Experts (blogs, suppliers) generally arrive at a range of 5-20 degrees centigrade (40-70 fahrenheit) as an acceptable range to keep the coffee - preferably towards the cooler end.
  • Segregate coffee from foreign odours. Keep coffee in a clean environment. Don’t put it around other odour-producing items, including foods or chemicals. This would mean, usually, its own container, drawer or cupboard.

What to do

I’ll boil this down in three levels - 1. Easy and acceptable, 2. Better but harder, and 3. Best and hardest. For all these methods, you must keep the coffee in a moderately cool, humidity controlled environment such as a cupboard in a room in which most people would be comfortable.

  • Easy and acceptable: Store your coffee in burlap or cotton bags in their own cupboard space. It’ll be good this way for up to three months, assuming the environment is controlled.
  • Better but harder: Use multi-laminate grain storage bags (like GrainPro). These are a grain storage bag that has gained popularity in the coffee world, and are basically a giant sandwich bag with zip lock, but built with multiple layers and a vapour barrier between them. It has been reported (by Sweet Marias, citing an article in Roast Magazine) that storing coffee in GrainPro bags can increase shelf life by up to 3-6 months. Conservatively, this means you can store this way for up to six months, again assuming climate control.
  • Best and hardest: Use vacuum packing. This is time consuming on a large scale, but easy to do for a home hobbyist. Buy some vacuum packing bags, store coffee in them, and seal them with your vacuum cleaner. If you do this and use multi-laminate bags and have climate control, you can store for up to 9 months.

Hope that's helpful! Any questions, use the contact us page to talk to us at any time.