How do you store fresh coffee beans?

[Jenise]

When I first started buying whole bean coffee--not exactly Jurrassic times, but well before I ever heard of Starbucks--to maintain coffee freshness it was considered mandatory to store coffee in the freezer. Somewhere along the way, though, concern about freezer burn/odors changed my thinking about that, and since I can now self-serve in any small quantity I please from a good local roaster right there at my grocer's, I only buy about two weeks' worth (about 1/3 lb) at a time and just keep it in the pantry.

What are your coffee buying/storing habits?

We buy our beans six pounds at a time to avoid paying S&H. It does not arrive in vacuum sealed bags, so rebag it tightly in plastic storage bags and freeze. They last about three months and stay fresh this way.

I buy a pound or so at a time, which lasts us a couple of weeks at the most. It sits in an ceramic crock that has a lid with a silicone seal that keeps the air out. I find that it's always gone before I start noticing any staleness to the brew.

I use a large glass jar with a silicone seal and clamp lid.

I use a mason jar and seal it with my Foodsaver. Works great!

If the beans are well sealed freezer burn shouldn't be a concern. I understand the problem with keeping beans in the freezer to be that every time the container is opened some amount of water condenses on them, affecting quality in some way. I go the the air-tight-in-a-cool-place route and, like others here, don't notice a problem despite sometimes buying several pounds. I expect the ultimate approach is Patti's, using a Foodsaver with either one of their custom canisters or the mason jar attachment to not just exclude air but remove it. I keep stuff like dried porcini and nuts that way more or less forever but get into the coffee often enough that I don't want to bother - just air-tight seems to work well enough.

At work, I keep my 1 lb orders of beans in a ceramic crock fitted with the silicone seal and a clamp. At home, where consumption is slower (only on weekends) I keep my 1/2 lb order in a Ziploc bag in the freezer. Whenever I open it, I squeeze all of the air out before resealing. In this way, my beans still smell "fresh roasted" a month after getting them.

Mark Lipton

I have tried many ways of storing beans over the years, but have settled on using a food saver bag unit to vacpack the beans and freeze the packs. I typically pack them in 6-8 oz quantities. I keep two weeks worth of beans in a jar with a silicone seal that provide my daily use. I detect significant fall off in bean flavor and aroma by the end of two weeks, so if I haven't finished the beans in the jar by then, I pitch them and use one of the vacuum packed bags of beans. The beans that come out of the freezer are still fresh enough that they continue to degas for a few days.

All of this assumes that you get the beans within a couple of days of roasting.

I have tried many ways of storing beans over the years, but have settled on using a food saver bag unit to vacpack the beans and freeze the packs. I typically pack them in 6-8 oz quantities. I keep two weeks worth of beans in a jar with a silicone seal that provide my daily use. I detect significant fall off in bean flavor and aroma by the end of two weeks, so if I haven't finished the beans in the jar by then, I pitch them and use one of the vacuum packed bags of beans. The beans that come out of the freezer are still fresh enough that they continue to degas for a few days.

All of this assumes that you get the beans within a couple of days of roasting.

Greg,
You would know best, but I would have the same concerns about vacuum sealing coffee as I have about Vacu-vins and their ilk: you are removing some of the volatiles when you remove the air. I agree about the aging of the sealed beans and the loss of the aromatics. It's those volatile thiols that I most value in coffee, and those are what are most easily lost.

Mark Lipton

Mark, that was a concern of mine as well. I don't like the vacuvins for precisely that reason. That said, I have let taste make the decision for me. While YMMV, this has been the best choice for me.

I wonder if the volatiles that are associated with coffee beans are less volatile than the aromatics from wine for a variety of reasons. For instance, they are also in bean form, rather than liquid, which may make the volatiles less susceptible to the very low level of vacuum produced in a food saver. When I grind beans, I find they lose their aroma very quickly, measured in minutes (I have seen references to this happening because the grinding breaks the cell walls and releases the volatiles, solubles and particulates making them available for liquid extraction). If true, a low level of vaccum may not have a major impact on beans.

When stored at room temp in an airtight container in bean form, they maintain their aroma out to two weeks.

Clearly, coffee beans have a lot of aroma at room temp, but much more when you brew them at around 200F.

There may be a number of things going on here.

G

I wonder if the volatiles that are associated with coffee beans are less volatile than the aromatics from wine for a variety of reasons.

Not using the standard definition of volatility, but I agree with the overall point.

For instance, they are also in bean form, rather than liquid, which may make the volatiles less susceptible to the very low level of vacuum produced in a food saver. When I grind beans, I find they lose their aroma very quickly, measured in minutes (I have seen references to this happening because the grinding breaks the cell walls and releases the volatiles, solubles and particulates making them available for liquid extraction). If true, a low level of vaccum may not have a major impact on beans.

This is the crux of the matter. Most of the volatiles are trapped within the beans and not susceptible to evacuation. Wine, in contrast, can be degassed if the pressure drops low enough, resulting in the loss of lots of volatiles. Put another way, it's a lot easier to evaporate things from a liquid than to remove them from within a solid matrix.

Clearly, coffee beans have a lot of aroma at room temp, but much more when you brew them at around 200F.

There's actually a known chemical transformation going on there, resulting in the characteristic smell of fresh-brewed coffee (2-thiolmethylfuran) but I won't bore you with the details.

Mark Lipton

I buy a pound at a time - a week's worth, and keep them in a paper bag in the fridge.

When I first started buying whole bean coffee--not exactly Jurrassic times, but well before I ever heard of Starbucks--to maintain coffee freshness it was considered mandatory to store coffee in the freezer. Somewhere along the way, though, concern about freezer burn/odors changed my thinking about that, and since I can now self-serve in any small quantity I please from a good local roaster right there at my grocer's, I only buy about two weeks' worth (about 1/3 lb) at a time and just keep it in the pantry.

What are your coffee buying/storing habits?

A third of a pound lasts you two weeks? Geez, I go through a pound a week.

I'm in charge of the coffee club at work. I buy 6-52 oz. plastic re-sealable cans of ground Folgers at a time from Sam's Club. At home I store my whole bean coffee in one of these containers. I don't freeze or refrigerate the coffee. I also use the containers to store rice, sugar and flour in my pantry.

I frequently buy green beans and roast them (usually a French roast) as needed in my coffee roaster. Green beans don't go rancid.

Howie's post mentions plastic resealable cans. I like to reuse cans, too, but I tend to prefer the metal ones to store nuts and bolts and other stuff. No doubt metal ones will go the way of the dodo bird someday. What kind do you prefer? I know, I know. Some coffee drinkers would avoid even glancing at a coffee can or walking down that grocery aisle, but unless your office can afford the foo-foo stuff there's always a supply of cans available for recycling.

When I first started buying whole bean coffee--not exactly Jurrassic times, but well before I ever heard of Starbucks--to maintain coffee freshness it was considered mandatory to store coffee in the freezer. Somewhere along the way, though, concern about freezer burn/odors changed my thinking about that, and since I can now self-serve in any small quantity I please from a good local roaster right there at my grocer's, I only buy about two weeks' worth (about 1/3 lb) at a time and just keep it in the pantry.

What are your coffee buying/storing habits?

A third of a pound lasts you two weeks? Geez, I go through a pound a week.

The third of a pound that I mentioned in one of my posts doesn't last two weeks. I have multiple different beans going at a time. So, I usually have a total of about a pound and a half or more open at once.

I should say, that I am drinking almost exclusively espresso which I find is more sensitive to freshness than brewed coffee.

A third of a pound lasts you two weeks? Geez, I go through a pound a week.

The third of a pound that I mentioned in one of my posts doesn't last two weeks. I have multiple different beans going at a time. So, I usually have a total of about a pound and a half or more open at once.

I order 1.5 lb of coffee about every 2 months, which is why I am so concerned about storage. At work, I'll go through a lb in about 7 weeks, drinking a cup per day, 4-5 times per week. At home, I go through a 1/2 lb in about the same time, drinking a cup a day on the weekends. When I think of the cost of a cup of Starbucks, the savings are considerable ($18 for me vs. $77 for the Starbucks)

I should say, that I am drinking almost exclusively espresso which I find is more sensitive to freshness than brewed coffee.

That's ironic, since the story I've heard is that the Espresso process was invented as a way to make a drinkable cup from older beans.

Mark Lipton

A third of a pound lasts you two weeks? Geez, I go through a pound a week.

The third of a pound that I mentioned in one of my posts doesn't last two weeks. I have multiple different beans going at a time. So, I usually have a total of about a pound and a half or more open at once.

I order 1.5 lb of coffee about every 2 months, which is why I am so concerned about storage. At work, I'll go through a lb in about 7 weeks, drinking a cup per day, 4-5 times per week. At home, I go through a 1/2 lb in about the same time, drinking a cup a day on the weekends. When I think of the cost of a cup of Starbucks, the savings are considerable ($18 for me vs. $77 for the Starbucks)

I should say, that I am drinking almost exclusively espresso which I find is more sensitive to freshness than brewed coffee.

That's ironic, since the story I've heard is that the Espresso process was invented as a way to make a drinkable cup from older beans.

Mark Lipton

Are your beans ground ahead or are you grinding them for each cup?

Brief history of the origin of espresso:
People are in a hurry. For many workers, waiting five minutes for coffee to brew is too long. They were also in a hurry 100 years ago when inventors started looking for faster ways to brew coffee to order. It being the age of steam, the first attempts used steam rather than water. A steam brewing contraption at the 1896 World's Fair is said to have made 3000 cups per hour. Unfortunately, steam-brewed coffee tastes awful since coffee generally needs to brew at just below boiling (195-205°F or 90-96°C) to taste its best. In 1901, the Italian inventor Luigi Bezzera came up with a workable solution. Pavoni manufactured these first espresso machines in 1905.


Café Reggio's Pavoni

This machine was also steam powered. However, the steam does not come into contact with the coffee. Instead, steam pressure at the top of the boiler forces water at the bottom of the boiler through ground coffee. The coffee is held in a group consisting of a portafilter, a metal filter basket and removable brass mount, and a brew head into which the portafilter attaches. The piping and group were designed to act as heat radiators, so the temperature of the pressurized water dropped from 250°F (120°C) in the boiler to the correct brewing temperature at the grouphead. This brewing principle is still used in stovetop mochapots. Since the water was pressurized, the coffee could be ground finer than in a regular pourover brewer, reducing the minimum brewing cycle from about 4 minutes to 30 seconds. Espresso machines and their accompanying coffee grinders became the standard equipment for making coffee in Italy, Southern France, Spain and Latin America. In other parts of the world, it followed Italian immigrants who popularized it in each country they settled.

And for those who have way too much time on their hands, here is a link to a thesis length discussion on storing coffee beans.

http://www.home-barista.com/store-coffee-in-freezer.html

And a shorter version specifically for Mark to provide a chemical foundation for the discussion.

Storage of Roasted Coffee Beans to Maximize Flavor
by Bob Barraza

It is fairly common to hear from home roasters that the biggest improvement they have every made in their espresso is when they started roasting at home. They state that nothing brews like fresh roasted coffee. As a chemist, this makes a lot of sense to me since roasted coffee is so unstable and continuously deteriorating.

The thing that makes espresso unique amongst all coffee brewing methods is its use of CO2 in the extraction process. Under the conditions of temperature and pressure encountered in pulling a shot, the CO2 from the coffee dissolves in the water forming carbonic acid which lowers the pH (acidity) of the water. This in turn affects the relative solubility of the hundreds of components that reside in the coffee grounds and it changes the profile of the compounds that are extracted. As the extract starts to pour from the basket and it returns to ambient pressure, the dissolved CO2 boils off and creates that honey-like crema which lets us know that we are in the sweet spot. Not too different from popping the cork on a fine bottle of champagne!

So where did the CO2 come from? The coffee roasting process involves the oxidation or controlled burning of the coffee bean. In case you have forgotten, the oxidation of organic compounds results in almost entirely CO2 and water as the byproducts. Since CO2 is a gas at ambient conditions, the gas trapped in the beans will 'boil off' and slowly leave the roasted beans. Fresh roasted beans are loaded with CO2 , and they generally require about a day of 'out gassing' before they make excellent espresso.

I have often read that the best espresso is made from beans that are 2 to 10 days post roasting. I am not surprised that there is a lot of controversy over this range because it will eventually be a subjective preference over the profile of compounds that are extracted. Remember that the age will determine the amount of CO2 remaining in the beans which will not only impact the amount of crema but also the amount of carbonic acid in the extraction water.

So how can we keep the CO2 from escaping? Well, if we have an impermeable container made of either glass or metal with a metal cap and tight seal we can only slow the process down. Very freshly roasted beans in a gas-tight container could cause the container to burst, so some room for escape is needed. However, this type of container would also be an excellent way to protect the roasted beans from some of its other primary enemies: water, oxygen, and light.

The aromatic and flavor components created in the coffee roasting process are very fragile to say the least. They can quickly be degraded in the presence of water and/or oxygen by processes known as hydrolysis and oxidation. However, if kept dry, these delicate compounds are quite stable. The problem is that the roasted beans are super-dried during the roasting at high temperature and low humidity. In fact, the roasted beans finish up in an unnaturally dry condition. Given the chance, they will readily absorb moisture from the surrounding air. Even in an air conditioned environment there is sufficient moisture in the atmosphere for the beans to pick up enough moisture in a day or two to satisfy their thirst. Unfortunately this moisture will destroy the flavors that we are looking for in the cup.

So what kind of container works best? My favorite is a stainless steel canister that has a metal friction fit lid and a glass insert in the lid. This acts as a window to see the contents without having to open it. Keep in mind that every time the canister is opened there is an exchange of gases between the head space in the container and the ambient air which is your source of humidity and oxygen. These lids are not gas tight and they will not allow the CO2 to build up pressure. The good news is that as the CO2 leaves, it is taking some of the oxygen with it. Also, the metal can does not allow light to penetrate which acts as a catalyst for oxidation.

Some of my other favorite but less sexy containers are the Mason type canning jars, spaghetti sauce jars, and salsa jars. All of these have in common that they are made of glass and have metal lids. Warning: they require several cycles through the dishwasher before they are clean and odorless enough for use with your coffee, otherwise you will notice some unique 'oregano' and 'jalapeno' notes in your espresso! In fact, I recommend that you season the jars by storing your outdated coffee in them for a while to completely eliminate foreign odors.

Whether you roast at home, or buy freshly roasted coffee every week like I do, you will want to keep it as fresh as possible. Big containers with a lot of head space are not ideal. Use several small jars that will hold a few days supply and keep them sealed until ready to use. No need to refrigerate. In fact, if you open a jar that just came out of the refrigerator you will get lots of moisture condense on the cold beans just like it does on the milk jug when you pour milk for that cappuccino.

Based on the above, you will probably agree with me that the cute little brown bag with dog ears that we buy our precious beans in is less than ideal for anything other than quickly transporting the beans home. In fact, I take my jars to the shop and my friendly vendor weighs the coffee right into my funky sauce jars! Not quite Folger's 'locked in freshness' or Maxwell's 'good to the last drop', but a noticeable improvement over the paper sack.

I frequently buy green beans and roast them

So do I, but I never thought about making coffee with them.

Geez, I am surprised at the moderate coffee consumption of some people.

We are a half kilo a week household, and if I buy in any greater bulk (the occasioanl espresso mix) it goes into the freezer in sealed bags.

Are your beans ground ahead or are you grinding them for each cup?

I grind for each cup. I have a burr grinder at work and a hand grinder at home (my father's, which I inherited).

Brief history of the origin of espresso:

Thanks for the story, Greg. It makes perfect sense given the name 'espresso.' I still recall reading, though, that the process is less sensitive to the quality of the beans than normal filter brewing. Perhaps it's in the book "Uncommon Grounds." I'll see if I can find it in there.

Thanks also for the chemistry article. It sounds fairly reasonable, but I do worry a bit about this guy's chemistry. Gastight containers exploding from CO2 pressure buildups? Not bloody likely, especially when one considers how an increase in pressure will reduce the CO2 emission rate from the beans. The article reads like an interesting and appealing hypothesis without a lot of data to back it up. CO2 is far from the only volatile thing in roasted coffee, and some of the other volatiles, such as the furan thiol I mentioned, are known to be critical for the flavor.

Mark Lipton

I frequently buy green beans and roast them

So do I, but I never thought about making coffee with them.

Ding, ding, ding! You win! I was waiting with bated breath to see who would be the first to say that.

Jenise, it seems I recall that you drink one cup of coffee in the morning and then switch to tea, or something right? I guess that would account for what some would call a low-consumption rate.

Right now I'm buying Peet's Major Dickason's Blend (whole bean) at Ralph's, but they don't carry the whole bean decaf around here. (I mix my beans 1/2 caf/1/2 decaf.) So I buy a big blue bag of the Kirkland brand (Roasted by Starbucks) decaf from Costco and mix that with the Peet's in a glass container with silcone sealing lid (no clamp like Doug's though). The rest, I just keep in the cabinet under the counter (dark and cool) in the original packaging, sealed pretty well. I go through the stuff pretty quickly so I don't notice any diminished quality.

On the other hand, Len exclusively drinks iced coffee and for that, I make a cold-brewed concentrate for him out of the least expensive pre-ground coffee I can find. It takes 8 measuring cups of coffee to make him about three days worth. Usually it's the Kirkland brand. I don't transfer it out of the big cans I buy it in, and I definitely notice a deterioration in aroma a few days after opening it. Perhaps it's time to buy a vacuum sealer?