What is “Fresh Green Coffee?”
There’s a problem in the making for the home roasting community. We have struggled for years to improve our roasting techniques, to demand better roasting appliances. Many have turned their backs on the manufacturers, choosing to build their own air roasters and drum roasters from popcorn popper parts and barbeque grills. In 2004, if you are willing to pay the price (roasters are expensive!), to pay attention, and to make a few tweaks to your equipment, you can roast coffee at home better than some professionals who might have pricey equipment but bad technique.
But the problem is in seed … in the green coffee that we roast. I’ll be blunt; no matter how crafty you are with your Variac-regulated, PID-controlled, thermo-coupled roaster, you can’t turn crap into cake. Garbage in means garbage out.
In the greater commercial coffee trade, declining quality is to be expected. You can’t pay coffee farmers at current market prices and expect premium Specialty coffee. But there are other problems among the coffee sellers and buyers that are inexcusable. The first problem is the eroding definition of Specialty coffee. There are coffees being sold as Estate-specific that are not. There are brands developed by the coffee mills or even by the importers, applied to generic coffees to make them seem specialty. Some of these don’t fit even the most basic definition of Specialty coffee, that they are from a specific origin and have cup quality. And, most importantly, there is old coffee being sold to home roasting consumers, past crop or marginal current crop coffees. In this case, it could be a coffee of the best pedigree, with excellent cup quality … if it was fresh. But after sufficient time (or even a short time in bad storage conditions) the cup quality erodes and the coffee, no matter if it is top SHB, Grade 1, Micro-regional, Shade-Grown, Hard Bean, Fair Trade, Heirloom Cultivar, Sun-dried, Bird-Friendly or processed by monks one seed at a time – it will be a flat, baggy cup of cardboard-flavored brown water!!!
When I started in the trade we would talk about green coffee being “fresh” for 2 years or more. We were wrong! It was a fiction that we told ourselves as roasters, propagated by brokers who had warehouses full of old coffee to sell. But in 2004 it is a fiction that coffee sellers, roasted or green, continue to tell themselves (and their customers) because the alternative, selling off the coffee at a loss or even dumping it, is too painful.
But there is another problem; some new home coffee roasters don’t know what baggy old coffee tastes like, so there’s nobody to hold the coffee supplier accountable. Daily cupping is a lot of work, and many coffee sellers are not experienced cuppers, haven’t cupped with other professionals or in public settings and competitions. So they rely on a broker to tell them what is good, without verifying for themselves by evaluating each new offer against other current coffees, and against previous lots. We possibly end up with the blind leading the blind, and defective coffees sold as Specialty. It may save time and money to avoid rigorous cupping. But the difference in price between green coffee suppliers and coffee origins are insignificant amounts; it is more important that quality come before price. If a coffee costs $6 Lb. rather than $4 Lb. the difference amounts to 3¢ per cup. 3¢!
For our part, we are now offering another “educational” coffee (remember the Vietnam Gr.4 Robusta)? This time it is past crop coffee, and really not that old. It is 2002 crop and we are offering it at its fair market price given the cup quality: 70¢ per Lb. It is listed at the end of our coffee offering sheet as Ye Olde 1 Lb. Of Coffee -2002 Crop and I beg you to try it, listen to how it roasts, how the first crack sounds, and how it cups. There is so much more to discuss on this topic (origins that age quicker than others, how Sweet Maria’s handles our green coffee stock, Freshness dates –our reviews list lot/bag marks and arrival dates—and more). But this could fill 5 newsletters. There are indeed 3 more articles and info. sheets in our Coffee Library. Check them out at www.sweetmarias.com/articles.shtml!
What is “Fresh-Roasted Coffee?”
Put in perspective green coffee is physically dense and chemically stable compared to roasted coffee. I’ve just made it sound like green coffee ages in nanoseconds; really it is roasted coffee that has the lifespan of a sick flea!
The basic home roaster’s dilemma isn’t figuring ways to keep a pound of coffee fresh for as long as possible. The home roaster is usually fighting off the temptation to allow coffee some time to rest and de-gas after roasting before consuming the preciously small batch. For this reason, the home roaster doesn’t really need to consider seriously the many ways that coffee flavor degrades over time. But it’s useful to illustrate some of the basics of freshness, if for no other reason than to show the fragile nature of coffee flavor, and gain a greater respect for its complexity. And how else are we going to explain to non-roasters why our coffee is so aromatic and lively?
Chemical Basis of Freshness: The enemies of coffee flavor are open air (oxidation and dissipation of aromas), heat (coffee stored in warm environment), and moisture (high humidity especially). My dull and lifeless cup of Kenya is the perfect starting point, because East African coffees have an abundance of Aldehydes that account for their strongly attractive aromatics and fruit flavors. Aldehydes combine with acids during roasting to form aromatic Esters. Esters and aldehydes are the most volatile aromatic compounds, broken down by heat and moisture or oxidation/dissipation. Certain aromatics are diminished by 50% after ground coffee is left 15 minutes in open air!
The basic set of compounds responsible for perceived coffee freshness are a particular set of Sulpherous Mercapatans, and in particular Methyl Mercapatan. This chemical is lost rapidly through dissipation and oxidation, especially when ground coffee is left in open air in a humid environment. Lab results show noticeable loss in 24 hours, and up to 70% loss within 3 days.
Many compounds in coffee are perceived as positive in moderation, then as negative in higher concentrations. Furfuryl Mercapatan is one. At the very slight concentration of .01 to .5 parts per billion it communicates freshness to the senses, and any higher it is perceived as staleness! Such is the topsy-turvy world of coffee chemistry.
Phenols are sensed as spicy notes in darker roasted coffees, and especially noticeable in dark roasted Ethiopians or East Africans. Also in specific roast tastes you find Pyradines (smoky, ashy), Pyrazines (earthy, musty) and Pyrroles (smoky, roasty). Phenols evaporate easily. Pyrroles are more stable but are a negative taste sensation in greater concentrations. Pyrazines are highly volatile and dissipate easily. Pyrroles occur in the coffee oils and are subject to oxidation. The above compounds can be dramatically reduced or converted to negative flavors within 8-10 days of roasting, and much sooner under the influence of oxygen, heat and moisture.
In general, staling occurs as fats and oils are oxidized. As coffee takes on oxygen, Lipids are converted. The main undesirable compounds produced are Peroxides, and the more peroxides present the more will be produced…a sort of exponential regression into staleness. Also, fats are subject to aromatic taints, so keep coffee (both green and roasted) away from your onions.
De-gassing coffee is not immune to the effects of oxygen. It simply has less oxygen surrounding the coffee due to the presence of CO-2 gasses emanating from the fresh coffee. But it takes very little oxygen to stale coffee over time, so the key is to minimize exposure to oxygen, and minimize the time until the coffee is consumed.
Degradation of coffee flavor is inevitable, and pre-roasted coffee, whether it is packaged in a valve-bag or not, has inevitably lost flavor. So it makes sense that the simplest way to combat all the forces that ruin coffee quality over time is to reduce the time between roasting and consumption!
Sweet Maria’s Coffee
1455 64th Street, Emeryville CA 94608
email: [email protected]
Sweet Maria’s Green Coffee Offering List on Jan. 10 2004.
Central American 1 lb 2 lb 5 lb 20 lb
Costa Rican Auction Lot -El Legendario $7.50 $14.25 $33.75 $121.50
Costa Rican - La Magnolia $4.90 $9.31 $21.32 $75.46
Costa Rican La Minita Tarrazu $6.80 $12.92 $30.26 $108.80
El Salvador Chalatenango- Zona Alta $4.80 $9.12 $20.88 $73.92
Guatemala Antigua - Filadelfia Estate $5.20 $9.88 $22.62 $80.08
Guatemala Organic Coban - El Tirol $5.10 $9.69 $22.19 $78.54
Guatemala Huehuetenango-La Maravilla $4.80 $9.12 $20.88 $73.92
Honduras Org. SHG - Sebastian Melgar $5.10 $9.69 $22.19 $78.54
Mexican Oaxaca Pluma-Tres Oros 5142 $4.30 $8.17 $18.71 $66.22
Nicaragua Matagalpa Pacamara 19+ $4.90 $9.31 $21.32 $75.46
Nicaragua Matagalpa - San Martin Estate $4.50 $8.55 $19.58 $69.30
Nicaragua Cup of Exc. Co-op 22 de Sept. $6.50 $12.35 $29.25 $105.30
Panama Boquette -Finca La Berlina $5.40 $10.26 $23.49 $83.16
South American 1 lb 2 lb 5 lb 20 lb
Bolivia Organic Caranavi "Colonial" $4.50 $8.55 $19.58 $69.30
Brazil Fazenda Ipanema "Dulce" $4.50 $8.55 $19.58 $69.30
Brazil Matas de Minas -Fazenda Brauna $4.50 $8.55 $19.58 $69.30
Brazil Sul de Minas - Carmo Estate $4.40 $8.36 $19.14 $67.76
Brazil Organic/FT Poco Fundo $4.90 $9.31 $21.32 $75.46
Brazil Mogiana Estate Natural-Dry $4.60 $8.74 $20.01 $70.84
Colombian Huila Excelso Lot 6581 $4.40 $8.36 $19.14 $67.76
Colombian Organic Mesa de los Santos $4.90 $9.31 $21.32 $75.46
Peru Organic Norte -Perunor $4.50 $8.55 $19.58 $69.30
African- Arabian 1 lb 2 lb 5 lb 20 lb
Ethiopian Ghimbi Lot 5025 $4.20 $7.98 $18.27 $64.68
Ethiopian Harar Horse Lot 4338 $5.00 $9.50 $21.75 $77.00
Ethiopian Organic Sidamo Dry-Process $4.50 $8.55 $19.58 $69.30
Ethiopian Yirgacheffe Lot 4452 $5.20 $9.88 $22.62 $80.08
Kenya AA Auction Lot -Kanake $5.25 $9.98 $22.84 $80.85
Kenya AA Auction Lot -Kihenia $6.00 $11.40 $26.10 $92.40
Kenya AA Auction Lot -Ruiruiru $5.70 $10.83 $24.80 $87.78
Kenya AA Auction Lot -Thunguri $5.50 $10.45 $23.93 $84.70
Uganda AA Organic Bugisu $4.40 $8.36 $19.14 $67.76
Yemen Mokha Ismaili (Hirazi) $7.80 $14.82 $36.27 $124.80
Zambian AA Lupili Estate $4.60 $8.74 $20.01 $70.84
Zimbabwe AA Salimba Estate $4.60 $8.74 $20.01 $70.84
Indonesian- Indian 1 lb 2 lb 5 lb 20 lb
Bali Shinzan Arabica $5.60 $10.64 $24.36 $86.24
Indian Monsooned Malabar Coehlo's Gold $5.00 $9.50 $21.75 $77.00
Indian Mysore Nuggets Extra Bold $4.80 $9.12 $20.88 $73.92
Indian Pearl Mountain Peaberry $4.80 $9.12 $20.88 $73.92
Java Government Estate -Blawan $5.00 $9.50 $21.75 $77.00
Papua New Guinea -Kimel A 4689 $4.50 $8.55 $19.58 $69.30
Sulawesi Toraja Grade 1 $4.50 $8.55 $19.58 $69.30
Aged Sumatra Lintong $5.80 $11.02 $25.23 $89.32
Sumatra Iskandar Triple-Pick $5.30 $10.07 $23.06 $81.62
Sumatra Mandheling Gr.1-Lot 1613 $4.30 $8.17 $18.71 $66.22
Timor Organic/FT Maubesse $5.10 $9.69 $22.19 $78.54
Islands- Blends -Etc. 1 lb 2 lb 5 lb 20 lb
Jamaica Blue Mountain - Mavis Bank $19.40 $37.25 $90.21 5 lb limit
SM's Moka Kadir Blend $5.60 $10.64 $24.36 $86.24
SM's Espresso Monkey Blend $5.00 $9.50 $21.75 $77.00
SM's Classic Italian Espresso Blend $4.80 $9.12 $20.88 $73.92
SM's Decaf Espresso Blend $5.60 $10.64 $24.36 $86.24
SM's Liquid Amber Espresso Blend $5.30 $10.07 $23.06 $81.62
SM's French Roast Blend $5.00 $9.50 $21.75 $77.00
SM's Roasted French Chicory $4.80 $9.12 $20.88 $73.92
Decafs 1 lb 2 lb 5 lb 20 lb
African Highland WP Decaf Blend $5.50 $10.45 $23.93 $84.70
Brazil Prima Qualita WP Decaf $4.60 $8.74 $20.01 $70.84
Colombian Huila Natural Decaf $4.50 $8.55 $19.58 $69.30
Colombian Excelso Medellin WP Decaf $4.70 $8.93 $20.45 $72.38
Costa Rican El Sol Sundried WP Decaf $5.10 $9.69 $22.19 $78.54
Ethiopian Yirgacheffe WP Decaf $5.20 $9.88 $22.62 $80.08
Kenya AA WP Decaf $5.50 $10.45 $23.93 $84.70
Mexican Esmeralda Natural Decaf $4.40 $8.36 $19.14 $67.76
Panama WP Decaf -Panamaria Estate $5.20 $9.88 $22.62 $80.08
Sulawesi Toraja WP Decaf $5.10 $9.69 $22.19 $78.54
Sumatra WP Decaf $5.20 $9.88 $22.62 $80.08
Premium Robustas 1 lb 2 lb 5 lb 20 lb
Indian Organic Washed Robusta $4.20 $7.98 $18.27 $64.68
Uganda Robusta -Esco Farms 18+ $4.00 $7.60 $17.40 $61.60
Other! 1 lb 2 lb 5 lb 20 lb
Ye Olde 1 Lb. Of Coffee -2002 Crop $0.70 1 lb limit