Should the trade be recommending that its customers put their coffee in the freezer for best storage?One of the coffee trade’s longest-running debates has cropped up again following advice from a major Fairtrade brand.
The Cafedirect brand has recently issued an online guide to ‘perfect cafetiere coffee’, which includes the following guidance:“Storing your coffee…which brings us on to the next tip.Freezers are the best place to store coffee once it’s been opened…”
The question of freezing coffee, whether green bean, roasted whole bean, or roast-and-ground, is a matter of great contention, about which there has been much learned writing and international debate.Guidance has come from the American National Coffee Association’s ‘knowledge bank’, which states firmly:‘it is important not to refrigerate or freeze your daily supply of coffee’, although the organisation says elsewhere that green beans may be frozen for up to a month.
Among the vast amount of comment on the subject, a member of the Starbucks Green Coffee Quality group agrees that ‘when you freeze the coffee you use every day, the fluctuating temperatures create moisture in the packet, which can leave your morning cup tasting like cardboard’.
However, a poll around the British coffee trade has come up with opinion which goes against that, and in favour of the Cafedirect view.
“There has now been extensive research to suggest that under certain conditions, freezing is better than just storing coffee beans conventionally,” commented Peter James, of James Gourmet Coffee.“If the coffees in question are roasted, they need to be whole bean, straight from roast and of course of really good quality otherwise the whole exercise is a farce.”
At Union Hand-Roasted, Jeremy Torz supports the idea of freezing. “Yes, we do recommend freezer storage for those that are going to take more than a few days (five or six) to drink their ground coffee, or if they buy beans, more than a week to 10 days.
“We want to keep the oils present in the coffee from oxidising, and low temperature retards this process significantly.I do not believe that freezing causes damage to fruit acids and oils and any very small degradation is much less than the effect of stale or rancid oils created by oxidation.
“I do not recommend the fridge, as it’s too humid an environment and the moisture can carry odours from other foods into the coffee.Freezers are very low-humidity so odour taint is not an issue.”
At Drury, Marco Olmi agrees that oxidisation slowed down causes less damage, with one reservation:“yes for beans, and yes for a cafetiere grind – I would not freeze an espresso grind, because grind is massively affected by moisture levels.I would think your humidity levels would go all over the place, and I imagine you’d have to de-frost it, not just whack it into the portafilter!
“But cafetiere coffee would be less of an issue.Certainly, if you’re buying something from a supermarket which may be months old, you wouldn’t notice.”
The most comprehensive opinion on the matter was provided by Simon Bower (pictured) of Pollards, the roastery in Sheffield.
“A largely academically-justified rationale comes from the science of coffee staling.Coffee stales predominantly because the chemicals that give it flavour oxidise.So to keep coffee fresh the best option is to remove the oxygen (vacuum packing) or to replace the oxygen with something inert (gas flushing).
“However, if these are not available, for instance after the bag is opened, the next best measure is to reduce the speed of the oxidising reaction.
“To start an oxidisation reaction you need energy, which in the case of coffee staling comes from the temperature of the environment.The more energy there is, the faster that reaction occurs, and conversely the less energy available, the slower the reaction occurs.So if you put the coffee in the freezer, staling slows considerably as there is little or no energy available for the reaction to occur.
“But what is the case against freezing?There was a movement in the USA that claimed it was unsound practice as it damaged oils and surfactants that were involved in producing crema.There was also some suggestion that you needed to let the coffee defrost adequately as you would frozen meat.
“As far as damaging the oils/surfactants is concerned we have tried this recently with a kilo of coffee we found in my mother’s freezer when she defrosted it.It had been at minus 21c centigrade for more than four years.We took it out, ground it, and it made a coffee with a great crema.The coffee had lost much of its flavour but there was still loads of crema.
“As far as any suggestion of defrosting the coffee (as you would meat) is concerned then the Americans were making unreliable comparisons to foods that are preserved by freezing.Coffee is not like meat, which needs to be cooked throughout to a certain temperature to make it safe to eat, so it can be used straight from the freezer safely.
“I remember a packaging seminar at the SCAA conference in Seattle a few years ago.There were those of the coffee is a ‘dark art’ school of thought who were convinced that freezing coffee was a sure route to eternal damnation, and there were scientists who said they could argue the point with the backing of research and facts.
“Whats our guidance?Simple – freeze away, because it is a great way of preserving coffee and one I use at home.But do try to make sure the coffee remains dry and in an airtight container if at all possible.”