Recently I was looking online for natural slug repellent for my garden. I found that coffee grounds make a great repellent and caffeine makes a lethal pesticide for slugs! Going down an internet rabbit hole, I came across a query asking if decaf was bad for the environment. It made me wonder if my decaf was doing more then repelling slugs in my garden.
Is decaf coffee bad for the environment? Decaf coffee is produced with a variety of methods, chemicals and processes each with different factors that could be bad for the environment. Coffee farming and production has a storied history of environmental problems. The decaffeination process generally is of low risk of environmental harm.
Decafs environmental issues are small compared to coffee as a whole. Let’s look at current decaf processes and then dive into coffee as a whole!
An overview of Decaf processes
Decaf coffee has a few main processes to decaffeinate the coffee which are listed below.
- direct solvent method
- indirect solvent method
- swiss water/mountain water
- supercritical C02 method
- triglyceride method
I would guess about 99% of decaf is either the solvent method or a water process method. Almost no coffee is processed by C02 or triglyceride currently. Hopefully that changes as I think those methods would address some of the concerns people have with the direct process.
Direct/Indirect Solvent Method
When decaf was first invented, Benzene was used as a solvent to remove the caffeine in the direct method. That obviously is a very toxic substance and no doubt bad for the environment. Benzene quickly fell out of use. Lucky for us modern day drinkers we don’t have to worry about such harsh chemicals being used.
The direct/indirect methods are the same with the exception being whether the water contacts the beans or not. In the indirect method the solvent only interacts with the water once it’s separated from the beans. In theory no solvent ever touches the beans but that water is recombined with the bean’s at the end of the process.
The direct method is the one most people worry about in terms of health and the environment due the methylene chloride used in the process. If you want to read all the concerns of methylene chloride you can see this link from OSHA.
Looking further into the matter I discovered a study linked here that shows over a ten year period workers exposed to high contractions of methylene chloride versus non exposed workers showed no difference in their liver, cardiac or neurological health! No difference! With chronic exposure!
As for the environmental effects of methylene chloride, I couldn’t find an authoritative answer. According to Wikipedia it is not an ozone depleting chemical due to its short life in the atmosphere.
Will it be harmful if it were dumped in a lake or stream? Maybe. Reading the Handbook of Complex Environmental Remediation Problems, on biofilters (filters using microbes), it lists methylene chloride/dichlormethane as having good biodegradability.
Microbes present in the aqueous phase then biologically degrade the contaminants through oxidative and occasionally reductive reactions. In the microbial process, contaminants are converted to carbon dioxide, water vapor, and organic biomass.
Handbook of Complex Environmental Remediation Problems, section 3.7.4
Most modern decaf coffee processing facilities will have the latest and greatest technology to safely handle the residual methyl chloride whether with biofilters or other technology.
I furthered my research by reading the Qusac Decaf Company website which stated the following:
“Today, we continue to find new ways to reduce our consumption of natural resources, reduce our contribution to landfill sites, recovery and recycle our process water and recover and refine compounds from our decaffeination waste stream and heat recovery program all while increasing the extraction efficiency and producing the best tasting Eco-Friendly decaf on the market today.”
http://www.qusac.com/pages/get-educated/faqs/#q-3
I think this sums up the industry well. It’s in the decafinators best interest to reduce all waste from their process including chemicals such as methylene chloride. In the end it just saves them money to be environmentally minded.
I’m not going to stop drinking my decaf for the simple reason that most studies look at industrial uses of very concentrated methylene chloride. What is used in coffee decaffeination is a fraction of that. Combined with the roasting process which destroys methylene chloride, the causes for concern for health are likely low. That said I’m not a doctor and if its a concern for your health speak to a qualified professional not some guy on the internet!
Swiss water
The swiss water process/mountain water processes are basically identical in the fact the solvent used is water and is then filtered to remove the caffeine. Really the only difference is the name and some of the filter technology. Being proprietary processes the exact differences are unknown.
Triglyceride
The triglyceride method is the same idea as Swiss Water except triglycerides, like those from spent coffee grounds, are used as the solvent to capture the caffeine. Really the same method with a different solvent.
Supercritical C02
Supercritical C02 method is probably the most modern and sci-fi but really the same principle. C02 is highly pressurized and then used to wash the beans in a special chamber under pressure.
What is a supercritical fluid? Basically it’s the pressure and temperature state of a substance where it’s neither liquid nor gas but a strange combination of the two. Science! This property lets it effectively extract the caffeine and no other flavors that some of the other methods inherently extract.
The big drawback is it’s very expensive and can only be done on large scales. Sadly this novel method has gained little market share due to the much higher cost. I have read various opinions of coffee tasters that the CO2 methods creates a muted coffee overall. Nag summarizes the benefits well in his book Biosystems Engineering, ch 16.1;
“There are growing concerns of health and environment problems associated with the use of traditional solvent extraction techniques employed in consumer products. Carbon dioxide is a potential extraction solvent alternative to the traditional organic solvents. Supercritical CO2 has advantages of low cost, nontoxicity, high diffusivities with appreciable solubility, and low viscosity. Separating the solvent from the extract is easily accomplished by reducing pressure and returning CO2 to a gaseous state. The solvent can be recycled for further use.”
I’m sure there are other novel decaf methods out there that are really just an overview of the current used processes.
Does decaf harm the environment? I think the case that the decaffeination process specially harms the environment is probably a minor concern compared to coffee or many other products as a whole. Probably the most harmful part is the powdered caffeine that gets put into many other products and fed back into people. Poor med students staying up all night with caffeine pills, they’re such nice people…
Coffees environmental issues
Coffee is probably one of the dirtiest agricultural products and one of the most energy intensive you can buy. Pesticides, poor farming practices, deforestation, loss of habitat, global shipping, energy usage in roasting and more transporting to you the end consumer. Most conventional crops today follow a similar pattern but the big difference is the amount of energy required to produce coffee to its final form.
If you think of strawberries from Mexico or apples from Argentina those have to be picked, packed and refrigerated. Coffee has to be picked, processed out of the coffee cherry (various methods many are sun dried and mechanically stripped) then can be shipped off. On the plus side it doesn’t require refrigeration!
Once it finally reaches the roaster then it gets roasted using natural gas or electricity (which is probably generated from coal or natural gas) to create that tasty coffee with aroma of dried cherries and notes of lime. It gets packed up and shipped to the store or you. Finally you use more energy to boil water to brew your coffee. Sum total being pesticides, diesel fuel, natural gas, and sunshine. At least you can grow your own apples in most of north America pretty easy. Sorry coffee gardens no luck unless you live in Hawaii.
What’s the total carbon cost of all that? According to an article on serious eats linked here, it’s about 11 pounds of C02 per pound of coffee! Is that good or bad? Pretty low compared to your favorite pair of sneakers at about 30 pounds. Just to be clear this isn’t meant to choose any side of controversial environmental issues but just an comparison between different products you use in life. An informed consumer is a dangerous one!
Coffees economic issues
Though not strictly environmental in nature, economic issues in my opinion drive poor environmental practices. You can probably recall some company in the news for making a decision to pollute something because it was the lowest cost method (and technically legal), cough, Love Canal, cough! Now just imagine how much that happens in the impoverished nations producing coffee. It might be as simple as dumping the spent coffee cherries into the river. Is this polluting? I’ll leave that for you to decide.
Economic factors lead to other harmful environmental practices. A lot of the coffee producing world has a very poor population. In Mark Pendergrast’s book, Uncommon Grounds: The History of Coffee and How It Transformed Our World, there is story after story of the coffee farmers often not breaking even on their coffee production costs. This leads to low qualities of life, lack of sanitation, disease, and conflict. At times farmers have even burned entire crops of coffee because the sale price was so low due oversupplies. Imagine the hardships that would lead to and how the environment is probably last on that list to protect.
Finally the economics of coffee drives farming practices. Most coffee is produced in conventional coffee farms that are portions of clear cut forest. Loss of habitat, burning of trees, poor soil management, and large applications of pesticides are prevalent in coffee farms.
But wait, isn’t there shade grown and bird friendly certifications? Yes that is true but those are small numbers compared to the total amount of conventional coffee grown. I quickly searched to find a approximate percentage and Wikipedia shows about 24% of coffee is shade grown, through the total pounds has shrunk due to increases in total production volume of conventional coffee. You can read the Wikipedia article here.
Bird friendly coffee (no not the Jazz musician), is one of my favorite certifications because it tries to protect the entire ecosystem while economically growing coffee. Bird friendly gets its name from protecting the natural ecosystem on the coffee farm to protect the bird population as an integral partner to a healthy ecosystem. As a gardener I want lots of birds coming around and eating the slugs out of my garden! More tomatoes, peppers and greens for me! If you want a great read about all the benefits of bird friendly coffee visit the Smithsonian National Zoo here.
Exploitative labor issues
Exploitative labor is not directly an environmental issue but it does lead to environmental issues. Let’s be real for a minute. Coffee is probably in general one of the most environmentally damaging and exploitative crops in the whole world. Reading from the pages of Roast Magazine March/April 2020, pg 58 on the current coffee price crisis, the cost of production is higher then the sale price of coffee, shows how damaging coffee can be.
Coffee has a deep history of using exploitative and often slave labor to grow and harvest coffee for richer markets. Reading the book Uncommon Grounds it’s apparent how bad coffee has been for many peoples around the world. The theme is usually the same, richer nations exploit poor nations where coffee grows and introduce poor farming practices and encourage debt loading for expansion. This is not a commendation of everyone that does business in coffee producing countries but reading Uncommon Grounds shows a clear pattern of exploitation.
Sadly I think this still occurs today. Even local governments exploit poorer local workers as a means to sell coffee to the global market. Specialty coffee has been the biggest challenger to these practices both working directly with producers but also funding projects to produce higher grades to make wages and profits higher and benefit the producers more directly. There are many studies on the value chain of coffee and very little of it goes to the farmer. If that’s not bad for the environment I don’t know what is!
Transporting costs of shipping coffee from exotic places to you
Probably something you never considered was how much fossil fuels were required to transport your nice finely roasters decaf to your doorstep. Depending on origin you coffee probably started its journey on a truck front he field at least a couple dozen miles to a processing center which used some level of electricity however generated i.e. most likely coal or natural gas. Next the coffee was flo from Guatemala or Sumantra to a warehouse in the US (or wherever you live), next shipped by truck to a decaffeination processor, then tricked again to a roaster, roasted again with most likely coal or natural gas generated electricity, then packed and shipped again by truck to your place of purchase. Wow I know my head hurts just thinking how much diesel was burned shipping one pound of roaster coffee to your door!
Add in a few more miscellaneous items like those mentioned in the book The Coffee Book: Anatomy of an Industry from Crop to the Last Drop (fyi I haven’t read it but a snippet is available on google), mainly the diesel power crusher to remove the cherries from the beans or the natural gas forklift to unload them at the dock and into the truck. I doubt anyone has a true end to end analysis of the exact amount of energy required to ship coffee from orgin to your door roasted but it’s huge!
Roasting environmental concerns
Did you know that coffee roasting can release volatile organic compounds, particulates and other nasties? Probably not, I didn’t either until I read an article in Roast Magazine March/April 2020 about the permitting process for coffee roasters. The EPA has mandated pretty strict controls of roaster air leaving a roastery. Note that is for all coffee not specifically decaf just to be clear.
Disposal of spent grounds
Where do old coffee grounds go when they worn out and used up? Mostly the land fill! From what I have read online, Starbucks is very generous with giving you all the grounds you could want if you call ahead. Other than the occasional overzealous gardener few go to compost.
A novel company in the UK, Bio Bean, is working on generating bio-diesel and burnable coffee logs from spent coffee grounds. A complex process using hexane and methanol to produce bio-diesel. Looking at a few papers and articles online confirmed that process improvements are underway and much less toxic chemicals will be needed to extract the oils for bio diesel.
Waste from packaging and to go products
If you think the chemicals used in the traditional solvent process decaf are bad then you would be horrified at those in the packaging! All those nice shiny really posh black bags with the gold embossed logos. Yeah, they’re full of chemicals to make all the layers of foil plastic and complex one way valves needed to seal in that awesome decaf from that trendy local roaster. Bet you didn’t think of that.
Seriously go weigh your posh coffee bag and see how much it weighs, I’ll wait! Well if you’re like me and you save random empty coffee bags then you would have learned it’s probably around ½ oz of material. Ok not so much but if you consider that you might drink 50-100 bags a year if it adds up to a lot of waste.
If you’re a zero waste kind of person you could make a cool epoxy mosaic bar table with all your bags for the year. I’m not sure that really gets us anywhere though cool and interesting. Otherwise like most other people you just throw them out in the garbage, they are not recyclable generally. Perhaps you might luck into some of the less robust ones packed in kraft paper style bags that are compostable. This is a great option if you have a have a compost pile in your yard. You do have one right?!
Seriously the plastic waste from coffee bags worldwide is probably shockingly ridiculous. There are companies out there working to transform garbage into energy through heat recovery.
Where does that leave us coffee drinkers? A quick google search showed that an interesting company called Terracycle offers a coffee bag recycling program. I haven’t tried them and only visited their website but it might be your best option . Though at $92 USD for an 11x11X20 inch box that is pretty expensive. I would guess you can fit about 100 coffee bags in there so it is about $1 USD to recycle a complex multi-layer material. Not bad I suppose.
The next best option is to ask your favorite local coffee shop to consider using compostable bags or at least some level of recyclable coffee bags. The compostable paper bag would be best though probably the shortest shelf life and least protection for the coffee.
So where are we…
If you made it this far, congratulations! Go grab a nice cup of coffee or hopefully you were drinking one while reading this article.
For me I love my coffee and will continue to support the best roasters with the highest quality decaf. For the enviroment my biggest issue after writing this article the is waste from the coffee bags. I intend to be much more selctive if I can about the type of bags I buy. As a home roaster the good news is most green coffee is shipped in paper or simple plastic bags. Are the pastic bags any better, Im not sure, but I can at least reuse them a few times myself. Not quite zero waste but close.
If you enjoyed this please share it and read some of my other great articles like 42 Reasons to Drink Decaf here.
References:
- Pendergrast, M. (2019). Uncommon grounds: The history of coffee and how it transformed our world. New York: Basic Books.
- Madison, C. (2020). The Decaffeination Process. Roast, (March/April 2020), 70-75.
- Alleb, T (2020). Working with the Government, Permits and Emissions Requirements for Coffee Roasters. Roast, (March/April 2020), 33-45.
- Luttinger, N., & Dicum, G. (2006). The coffee book: Anatomy of an industry from crop to the last drop. New York, NY: New Press.
- Nag, A. (2010). Biosystems engineering. New York, NY: McGraw-Hill Professional.
- Meister, (2018, August 09). What Is Coffee’s Carbon Footprint? Retrieved August 02, 2020, from https://drinks.seriouseats.com/2013/10/calculating-coffees-carbon-footprint-energy-usage-to-farm-pick-ship-roast-brew-coffee.html
- Thurston, Robert W. (2020). Can the coffee price crisis be fixed? Roast, (March/April 2020), pg58-69.
- Shade-grown coffee. (2020, April 17). Retrieved August 02, 2020, from https://en.wikipedia.org/wiki/Shade-grown_coffee
- UNITED STATES DEPARTMENT OF LABOR. (n.d.). Retrieved August 02, 2020, from https://www.osha.gov/SLTC/methylenechloride/hazards.html
- Ecological Benefits of Shade-grown Coffee. (2019, July 12). Retrieved August 02, 2020, from https://nationalzoo.si.edu/migratory-birds/ecological-benefits-shade-grown-coffee
- KJ;, S. (n.d.). An evaluation of chronic methylene chloride exposure. Retrieved August 02, 2020, from https://pubmed.ncbi.nlm.nih.gov/8455098/
- Jay H. Lehr; Marve Hyman; Tyler Gass; William J. Seevers. Handbook of Complex Environmental Remediation Problems. DISCHARGES OF HAZARDOUS WASTE INTO THE ATMOSPHERE, Chapter (McGRAW-HILL, 2002). https://www.accessengineeringlibrary.com/content/book/9780070276895/chapter/chapter3
- Ahindra Nag. Biosystems Engineering. Supercritical Fluid Extraction Applications for Biosystems Engineering, Chapter (The McGraw-Hill Companies, Inc., 2010). https://www.accessengineeringlibrary.com/content/book/9780071606288/chapter/chapter16
- FAQs: Where Amazing Decaf Happens. (n.d.). Retrieved August 02, 2020, from http://www.qusac.com/pages/get-educated/faqs/
- Wilson, A. (n.d.). The man putting coffee into fuel. Retrieved August 02, 2020, from https://www.shell.com/inside-energy/coffee-into-fuel.html spoken interview