Using 3 independent labs from around the globe…
We have analyzed over 100 different coffees representing 46 different brands. Purity was found to be 65% higher in antioxidants, on average, than all of the other organic coffee brands that were tested. Furthermore, Purity ranked the absolute highest in antioxidant levels out of all the coffees tested, while also being free of mold and mycotoxins.
Why are antioxidants important?
Antioxidants are a natural defense mechanism against free radicals that can cause damage to genes, accelerating the aging process and actually leading to cancer and other diseases. The good news is…coffee is the richest source of antioxidants in the American diet! The even better news is that Purity Coffee contains more antioxidants than other leading brands, and the most antioxidants of any organic coffee!
To learn more about this best kept secret to coffee’s amazing health benefits, check out our article on antioxidants.
How did we achieve such outstanding results?
The answer is simple…First off, less than 1% of the world’s coffee producers source beans that are up to the Purity standard. Secondly, no other coffee company in the world roasts deliberately for health benefits.
And luckily, our coffee also tastes great, which is an added benefit of beautiful beans that are not scorched.
To see how PURITY COFFEE stacks up against the different types of coffees, check out the results below:
The 46 coffee brands that were tested
Summary of Purity Coffee’s Laboratory Testing
Approach to Testing:
It all started with a few ideas that we wanted to confirm, clarify, or simply explore. We wanted to:
- Review the scientific experiments and studies about coffee and health, organizing and categorizing as we go.
- Look into the claims that other coffee companies are making about coffee and health.
- Study the health properties of everyday coffees available for purchase from Amazon, Mistobox, Whole Foods Market, directly from the brand websites and in supermarkets in Chicago, IL and Greenville, SC (where Purity offices are located).
- Use all the evidence we’ve collected to find and roast the healthiest organic coffee that the science says is possible.
- Using the following 3rd party labs (independent ones that we don’t own ourselves), we send blind samples that are labeled with the year and a random 3-digit number:
- Universidade Federal do Rio de Janeiro, Brazil: Laboratório de Química e Bioatividade de Alimentos & Núcleo de Pesquisa em Café -NUPECAFÉ, Instituto de Nutrição.
- Silliker-Merieux Nutrisciences in Crete, Illinois, USA: 3600 Eagle Nest Drive, North Building, Crete, IL 60417
- University of Porto, LAQV/Requimte-Faculty Pharmacy; Rua Jorge de Viterbo Ferreira, 218 4050-313 Porto, Portugal
- The cupping, color range identification and acidity testing is done by Purity Coffee’s Director of Coffee, who is a Licensed Q Grader and Q Instructor and has 22 years in the specialty coffee industry. You can read more about what “specialty grade coffee” means in our journal. Tests are done at Ally Coffee’s SCA Certified Lab and Premier Training Campus in Greenville, South Carolina.
The testing information presented here took place from June 2016 to the present. We did some tests prior to this (cupping and analysis December 2015), but June was when we began a formal program. We did not run all the coffees through all the tests for the following reasons:
- Cost—We originally began by checking a few coffees in comparison to Purity. We did not do all coffees and we did not do all tests, because we primarily wanted to know more about our coffee and how it compared to a handful of other coffees of varying quality and price. We tested green coffees prior to purchasing to measure cleanliness and, in a couple of cases, antioxidant activity.
- Roast level—We checked acrylamide levels of several coffees, but if a coffee was darker than Purity, we did not test for acrylamide.
- Ochratoxin—This test is costly, so we only tested coffees that seemed competitive with Purity.
- CGAs—Many of these are done, however we did not test several coffees that were over 5 Agtron points lighter roasted than Purity. Also, we are switching to the Silliker lab in Illinois for testing, and those numbers will not be presented in the detail that the University of Rio’s numbers are provided (Rio tests for 11 isomers). For a definition of “Agtron” see the section called “THE TEST: HOW TO READ THE NUMBERS.”
- We only tested Purity for pesticides, lead, cadmium, and copper, at the request of several customers.
- Acrylamide: We did not get as many numbers as we hoped, because the University of Porto was unable to complete the additional 60 samples we sent. By the time we found out they could not test the samples, the coffee was too old and the results would have been skewed.
Charts of Results
|19 Submissions to Silliker-Merieux|
178 Coffees, both green and roasted
|104 Samples tested at Silliker|
154 Samples at Univ. Rio
23 Samples at Univ. Porto
|148 Roasted coffees||Includes Purity at several roast levels, green coffee blends, production batches, and test batches for consistency, staling, and change in compounds over time. These roasted coffees included regular, decaf and soluble regular.|
|65 Brands||For some brands we only tested one of their products, and for others we tested several of their products.|
We divided the brands into the following categories, which may or may not be actual recognized categories for the roasted coffee market:
|30 Green coffee samples||We tested primarily for yeast, mold and ochratoxin. Several for Bacillus cereus and CGAs. We received many more green coffee samples than these, but we only sent coffees that cupped acceptably to the labs. We only tested for pesticide when decided to contract/buy the coffee. This test is quite expensive, and because the coffee is Certified Organic, we only felt the need to do due diligence on a product we would present to customers.|
The Tests: How to Read the Numbers
Coffee flavor and appearance are directly related to the degree of roasting, which allows us to use a scale with actual numbered rankings for product development and quality. The machine we use to measure color in coffee is an Agtron Spectrophotometer. It is designed specifically to analyze of the degree of roast and of color/appearance variations. Agtron instruments use specific wavelengths of light to illuminate the sample surface and measure the reflected energy.
The results of analysis are displayed as a single “Agtron” number from 0 to 100. The higher the number, the lighter the coffee. Most consumer “light roasts” are roughly around 65 and above. “Medium roasts” are roughly between 50 and 65 Agtron. “Dark roasts” are below 50 Agtrons
Agtron level can be deceptive, though. The same coffee can be roasted many ways and end up at the same color level. Every choice in heat application over time impacts the way the hundreds of chemical compounds in a coffee bean are changed, and color can give us a general idea of the length of time the coffee was roasted.
Acidity is measured in pH. Most coffees have a pH between 4.7 and 5.3 pH. Purity Coffee tries to hit a 4.95-5.05 pH level for the balance we feel works best.
Mold and Yeast
Yeasts and molds (fungi) can be found in soil and air, as well as on or in various foods and processing environments. Coffee is grown in environments that have ideal conditions for mold to thrive. Many things can go wrong during coffee production, and often the result is a mold of some sort. Yeast (and bacteria) are also used naturally to process the coffee after picking, and our test results show residues are often left on the green coffee (pre-roasted) beans and linger in processing equipment.
Because most yeasts are single-celled organisms which form compact colonies, and most molds are filamentous multicellular organisms that form colonies, mold and yeast test results are measured in “colonies”.
Yeasts and molds can grow over a wide pH range, from pH 2 to above pH 9. The temperature range is also broad, from 5°C to 35°C. However, growth of some species can be above or below this range. Mold spores are almost certainly destroyed in coffee during the roasting process (over 400°F [204°C] and probably during hot brewing preparation). Food companies test for how many colony-forming mold spores are present for food safety reasons. There should be no mold in roasted coffee.
The reason Purity tests for mold and yeast is standard due diligence that food companies should perform. A few foodborne yeasts and molds may produce allergic reactions, and with many people experimenting with cold brew methods, especially ambient brew methods, any mold present in coffee could pose a health risk. (Side note: Please keep your coffee brewers—of any kind—clean!). We want our customers to have peace of mind when enjoying their cup of coffee.
The Center for Disease Control has a useful information page on mold and how it affects your health.
Ochratoxin A (OTA) is a naturally occurring foodborne mycotoxin found in a wide variety of agricultural products. Ochratoxin A is a toxin produced by some Aspergillus and Penicillium fungi. Mold and other fungi “eat” by releasing enzymes that break down their food into a form the fungi can absorb. Certain fungi produce toxic byproducts of this process called mycotoxins, and OTA is the one that is associated with coffee most often. In addition to coffee, OTA is known to occur in cereals, dried fruits and red wine. It can accumulate in animal tissue and may cause cancer in humans. Mammals who ingest OTA can be at a high risk for cancer, and it can lead to acute toxicity of the kidneys.
The FDA does not provide any Action Level for this toxin, meaning they don’t have any safeguards or controls against its presence in food items. The European Union Action Levels differs by food product, and roasted coffee beans and ground coffee limit is 5.0 µg/kg (instant coffee is 10.0 µg/kg). (µg = microgram)
Aflatoxin is a toxin produced as a by-product from the mold, Aspergillus flavus. It is one of the most potent carcinogens known. It has been linked to a wide variety of health problems in both humans and animals. Besides being proven to cause cancer in humans, aflatoxins also cause great loss of livestock due to diseases resulting in reduced efficiency of production. Results are calculated as parts per billion (ppb) total aflatoxin. (ppb= µg/kg)
Bacillus cereus is an emetic toxin that is in the environment, forms in food, is heat resistant, and causes vomiting and other digestive disorders through growth in the gut. B.cereus has been known to be found on green coffee after processing. It should be destroyed during roasting, however. That said, Purity will not purchase a green coffee that tests positive for B.cereus presumptive. The “presumptive” is a general test, because there are different bacilli that are closely related, and the test will give a positive result if any type is found, not just B.cereus. Results are given as a count of B.cereus (<10/g)
Purity double checks for pesticides, even though we only buy certified organic coffees. The test is a composite of 310 chemicals (please see last page of this report for the list of chemicals).
Lead, Cadmium and Copper
Metals and other elements can be naturally present in food or can enter food from industrial and agricultural processes. The toxicity is in part due to the fact that these metals accumulate in a living organism’s biological tissues over time because they’re exposed to these substances in food and the environment. Several customers asked Purity about the levels of these metals in our coffee, so we tested to find out. The FDA has information on these metals on its website. Results are measured in parts per million (ppm).
It is hard to estimate the amount of these substances in a cup of coffee, but here is a general calculation: Based on the test results, there MIGHT be as much as 0.23mg in an 8-ounce strong cup of coffee (strong meaning a 1:15.5 ratio of grams of coffee to grams of water). HOWEVER, that is just based on the dry weight of the coffee. This would assume that all copper in the dry coffee dissolves into the finished brew, which is unlikely, since about 75% of the ground coffee is discarded after brewing has extracted the dissolvable compounds. The FDA says 0.9mg copper per serving of anything is the maximum recommended amount. Therefore, a cup of strong Purity dissolving all copper possible (again—unlikely) is still well below that limit.
Acrylamide is contained in many plant-based foods and nearly every food that is baked, roasted, or fried, including most nut butters, cereals, breads, and crackers. Coffee, too. Acrylamide is a human neurotoxicant and can impact the kidneys and reproductive organs. There is an explanation here of acrylamide by the U.S. Department of Health and Human Services Public Health Service Agency for Toxic Substances and Disease Registry.
Acrylamide is measured in micrograms per kilogram. Using a very general brewed coffee recipe, the maximum acrylamide is in a cup of brewed Purity Coffee (not using a paper filter) might be 0.59 µg/kg, however acrylamide is known to be even lower when coffee is brewed. By contrast, a 6-ounce serving of French fries (from a common fast food chain) has about 73µg/kg of acrylamide.
Chlorogenic Acids (CGAs)
CGAs are Chlorogenic Acids, which are phenolic compounds linked to antioxidative activity. Our testing results score is a composite of 9 tests done at the lab in Rio de Janeiro. The results here are measured in grams of CGAs per 100 grams roasted, ground dry coffee (g/100g). Extraction differs so widely between brew methods, grind size, water temperature and ratio of coffee-to-water used, that giving “cup of coffee” results would be too inaccurate to be acceptable.
Trigonelline (Trig), a niacin-related compound, is a natural component of roasted coffee and has been linked to antioxidant activity. Trigonelline corrects hyperglycemia, reduces oxidative stress and contributes to the therapeutic effect coffee has on non-alcoholic fatty liver diseases.
The Journal of Chromatography B demonstrated by molecular modeling that trigonelline showed similarities to that of an anti-Alzheimer’s disease drug candidate – cotinine. Known as a nicotine-related compound, trigonelline was taken into consideration for the study as an anti-Alzheimer’s disease drug candidate. Also, chlorogenic acid and trigonelline ingestion significantly reduced glucose and insulin concentrations.
Over-roasting coffee destroys CGAs and trigonelline, and Purity tests to make sure we are retaining as much as possible. Test results are measured the same as CGAs: 100 grams roasted, ground dry coffee (g/100g).
People can have vastly different reactions to caffeine, and for people who react badly to caffeine it is important to know the amount of caffeine in their coffee. The caffeine content of the many non-decaffeinated coffees ranged from 0.74 to 2.09 g/100g in the dry weight (Purity was about 1.23g/100g)
Coffee cupping is the practice of evaluating the different aroma, taste and body characteristics of a coffee to determine coffee quality. As an international commodity and globally appreciated food product, cupping is required for the coffee industry to communicate taste and quality to others all over the world. Companies and organizations have developed their own methods of cupping over time, which may work for them internally, but can cause miscommunication between parties in the market.
There are commonalities in most methods of cupping, from roasting the samples through final numeric scoring of the coffee, but Purity uses a modified version of the Specialty Coffee Association cupping method and form. The method was modified, because it was designed to evaluate green coffee quality, and most of the coffees Purity tested were roasted darker than the green coffee evaluation Agtron.
Cupping scores recorded here were done by a licensed Q Grader, cupping instructor and industry veteran of over 20 years. Scores can range from 0 to 100.
Number of Coffees Tested for Each Variable
|Number of Samples|
|Mold/yeast||63||23||Unfortunately, one set of Univ. of Porto results for Ochratoxin A and acrylamide were unusable (we lost 60 coffees).|
B. cereus was tested in Purity to determine any possible contamination at any part of the chain.
Pesticides tested in green coffee before purchasing.
Metals tested in roasted Purity
|Ochratoxin A (HPLC)||21||20|
|Bacillus cereus- Presumptive||1||17|
|Acrylamide||23||n/a||Tested at University of Porto and Silliker-Merieux|
|Chlorogenic Acids||144||Tested at the Federal University of Rio de Janeiro, Dept. of Nutrition|
|Cupping Scores/Sensory Evaluation (Using a SCA method modified for production roasting, Certified Q-Grader)||107||Green coffee cupping forms are on file, but not included in the results. All 30 coffees scored 80+, except for the Mexico Robusta.|
|Roast level (Agtron- using Javalytics)||126||n/a|
|Acidity (using standard pH meter)||76||n/a|
Number of Coffees Found with Problems
|Tested For…||Number of Samples|
|Notes (Metric/definition of issue)|
|Mold/yeast||4/63||19/23||Should be zero mold in roasted coffee. Green coffee mold an industry problem. Colonies ranged from 10-5400.|
|Ochratoxin (HPLC)||5/21||1/20||Ochratoxin ranged 0.2 - 1.4 µg. These green and roasted coffee are unrelated. The green coffee was for Purity purchasing decisions, the roasted coffee was to see whether other companies had OTA in their finished products.|
|Bacillus cereus- Presumptive||0/1||1/17||Did not purchase the coffee with B. cereus.|
|Lead||0.03 ppm||These results are for Purity roasted coffee per 100g. Brewed ppm will be far lower and all are at the lowest end of the FDA recommendations.|
|Acrylamide||14/25||The contamination numbers here represent those coffees that scored higher than 200ug acrylamide roasted dry coffee weight. These coffees ranged from 45-100 Agtron.|
|Cupping Scores/Sensory Evaluation (Using a SCA method modified for production roasting, Certified Q-Grader)||67/107||The cupping scores here represent coffees below specialty grade (80+).|
|Roast level (Agtron- using Javalytics)||40/126||These scores represent coffees roasted so dark as to likely have polycyclic aromatic hydrocarbons-PAHs. The range is 19-45 Agtron units (lower is darker—19 is almost black).|
|Acidity (using standard pH meter)||32/76||This number represents coffees that are too acidic (£4.8pH) and too alkaline (³5.2pH)|
Results by All Brands (Average)
|Purity Coffee 100% Organic|
|100% Organic Coffee|
|Some organic, not all|
This data represents 55 brands (some were deleted because of soluble, decaf, robusta blends or k-cups)
Coffees ranked by Cupping Score (taste), Chlorogenic Acids and Trigonelline (antioxidants)
(blank cells = the coffee was not tested for the variable)
|Brand Code||Agtron||Acidity||Mold||Yeast||CGAs||Trigon.||Ochratoxin||Acrylamide||Cupping score* (Purity Format)|
|1||PURITY 100% Organic||59||4.99||<10||<10||2.1||1.16||<0.2||196||85|
|2||Coffee Brand 11||60||4.65||1.7||1.2||689||85.3|
|3||Coffee Brand 2||46||4.94||1.42||1.13||81.1|
|4||Coffee Brand 10||66||4.78||<10||<10||1.46||1.06||<0.2||79.3|
|5||Coffee Brand 28||62||4.91||<10||<10||1.49||0.86||<0.2||160||77.7|
|6||Coffee Brand 8||58||4.93||1.87||1.09||280||76|
|7||Coffee Brand 34||67||<10||<10||1.62||0.83||220||76|
|8||Coffee Brand 3||56||<10||<10||1.32||1.13||1.4||718||75.5|
|9||Coffee Brand 16||50||4.85||<10||<10||1.68||1.01||<0.2||73|
|10||Coffee Brand 27||51||4.98||<10||<10||1.72||0.87||73|
|11||Coffee Brand 13||53||5||<10||<10||1.19||1.04||0.3||71.5|
|12||Coffee Brand 15||78||<10||<10||2.22||0.99||<0.2||260||71|
|13||Coffee Brand 24||40||5.31||<10||<10||0.97||0.94||71|
|14||Coffee Brand 23||56||5||<10||<10||0.96||0.96||70.5|
|15||Coffee Brand 14||60||4.96||<10||<10||1.46||1.04||<0.2||70|
|16||Coffee Brand 29||47||5.32||<10||10||0.76||0.86||<0.2||68.7|
|17||Coffee Brand 19||36||1.08||0.98||68|
|1||Coffee Brand 26||40||5.61||<10||<10||0.92||0.91||68|
|2||Coffee Brand 21||44||5.2||1.42||0.97||805||67.3|
|3||Coffee Brand 12||50||4.93||1.49||1.05||<0.2||160||67|
|4||Coffee Brand 37||41||5.4||0.81||0.81||67|
|5||Coffee Brand 4||45||5.29||<10||<10||1.47||1.13||<0.2||1053||66.5|
|6||Coffee Brand 17||51||5.1||<10||<10||1.57||0.99||65|
|7||Coffee Brand 32||49||4.94||<10||<10||1.55||0.84||64|
|8||Coffee Brand 20||56||5.01||<10||<10||0.99||0.98||62|
|9||Coffee Brand 40||41||5.38||<10||<10||1.09||0.78||62|
|10||Coffee Brand 45||74||<10||<10||1.14||0.53||61|
|11||Coffee Brand 22||50||4.89||1.24||0.97||60|
|12||Coffee Brand 44||58||4.85||<10||<10||1.45||0.61||59|
|13||Coffee Brand 25||48||<10||<10||1.56||0.93||58|
|14||Coffee Brand 30||48||5.03||<10||<10||1.76||0.85||56.7|
|15||Coffee Brand 6||50||4.88||<10||<10||0.93||1.12||0.2||56|
|16||Coffee Brand 38||40||5.11||<10||<10||0.92||0.81||56|
|17||Coffee Brand 39||44||5.3||<10||<10||1.09||0.81||55|
|18||Coffee Brand 41||40||5.23||<10||<10||1.1||0.78||55|
|19||Coffee Brand 31||40||<10||<10||1.37||0.85||54|
|20||Coffee Brand 33||47||5.35||<10||<10||1.02||0.84||54|
|21||Coffee Brand 42||34||5.3||<10||<10||1.49||0.67||53.5|
|22||Coffee Brand 46||35||5.58||10||<10||1.36||0.51||<0.2||53|
|23||Coffee Brand 35||30||5.6||<10||<10||0.85||0.82||<0.2||142||50|
|24||Coffee Brand 43||37||5.36||<10||<10||1.04||0.66||50|
|25||Coffee Brand 9||45||5.2||<10||<10||1.09||1.08||0.3||374||42|
|26||Coffee Brand 5||50||20||<10||1.43||1.12||<40|
|27||Coffee Brand 7||30||20||<10||1.11||1.1||<0.2||<40|
|28||Coffee Brand 18||45||5.11||<10||<10||0.98||0.98||0.2||250||<40|
|29||Coffee Brand 36||55||5.15||<10||<10||1.69||0.81||<0.2||<40|
Results by Brand Averages: Chlorogenic Acids
|Purity Coffee 100% Organic|
|100% Organic Coffee|
|Some organic, not all|
*When we average in the Purity Very Light into our coffees, like Brand 15. Cupping score lower because coffee is off balance.
*Brand 15’s data is based on 2 coffees they offer: One very dark, and one extremely light and under-roasted, which retains more CGAs, but is not a level most consumers want to drink. The color reading average is about 20 units lighter than Purity.
**We roasted our Purity Coffee green beans to the same level as Brand 15. When we roasted Purity very light, we could be as high (higher) than others. PLEASE NOTE: The coffee does not taste balanced at this level, and Coffee Brand 15 cup score was below specialty grade, having unpleasant flavor notes. Purity score at this roast level still scored Specialty, but we do not feel this is a roast level we want to offer our customers at this time.
|PURITY with light roast averaged in like Brand 15|
PURITY current roast
|Coffee Brand 15*||78*||2.22||71|
|Coffee Brand 8||58||1.87||76|
|Coffee Brand 30||48||1.76||57|
|Coffee Brand 27||51||1.72||73|
|Coffee Brand 11||60||1.7||85.3|
|Coffee Brand 36||55||1.69||<40|
|Coffee Brand 16||50||1.68||73|
|Coffee Brand 34||67||1.62||76|
|Coffee Brand 17||51||1.57||65|
|Coffee Brand 25||48||1.56||58|
|Coffee Brand 32||49||1.55||64|
|Coffee Brand 12||50||1.49||67|
|Coffee Brand 28||62||1.49||78|
|Coffee Brand 42||34||1.49||54|
|Coffee Brand 4||45||1.47||67|
|Coffee Brand 14||60||1.46||70|
|Coffee Brand 10||66||1.46||79|
|Coffee Brand 44||58||1.45||59|
|Coffee Brand 5||50||1.43||<40|
|Coffee Brand 2||46||1.42||81|
|Coffee Brand 21||44||1.42||67|
|Coffee Brand 31||40||1.37||54|
|Coffee Brand 46||35||1.36||53|
|Coffee Brand 3||56||1.32||75.5|
|Coffee Brand 22||50||1.24||60|
|Coffee Brand 13||53||1.19||71.5|
|Coffee Brand 45||74||1.14||61|
|Coffee Brand 7||30||1.11||<40|
|Coffee Brand 41||40||1.1||55|
|Coffee Brand 40||41||1.09||62|
|Coffee Brand 9||45||1.09||42|
|Coffee Brand 39||44||1.09||55|
|Coffee Brand 19||36||1.08||68|
|Coffee Brand 43||37||1.04||50|
|Coffee Brand 33||47||1.02||54|
|Coffee Brand 20||56||0.99||62|
|Coffee Brand 18||45||0.98||<40|
|Coffee Brand 24||40||0.97||71|
|Coffee Brand 23||56||0.96||70.5|
|Coffee Brand 6||50||0.93||56|
|Coffee Brand 38||40||0.92||56|
|Coffee Brand 26||40||0.92||68|
|Coffee Brand 35||30||0.85||50|
|Coffee Brand 37||41||0.81||67|
|Coffee Brand 29||47||0.76||69|
Pesticide Test: 310 Chemicals
Captan and metabolites
Chlordane (cis & trans)
Endosulfan (alpha + beta)
Methyl pentachlorophenyl sulfide
Permethrin (cis + trans)