Is Coffee Acidic? pH Levels, Taste, and Brewing

Coffee is acidic. The pH of coffee falls between 4.85 and 5.4 on a 0–14 scale, according to a 2018 study in Scientific Reports, though values vary. Roasting temperature, brewing temperature, and type of coffee bean are factors that affect the pH of coffee. Coffee “acidity” refers to the bright, tangy, or crisp taste you perceive, not its pH. Coffee tastes acidic because it contains natural acids, like citric acid (found in lemons), malic acid (found in apples), quinic acid, and a few others.

To lower acidity, choose a dark roast, use Robusta beans, or brew at cooler temperatures. Coffees from low-altitude regions like Brazil, Sumatra, and Bali tend to be least acidic. Pair low-acid brands (e.g., Colipse) with cold brew, French press, or AeroPress for a smooth cup without sacrificing complexity. Drinks with the lowest acidity include cold brew, nitro cold brew, espresso, and Americano. After brewing, used coffee grounds become nearly neutral and are safe for most soils.

What is pH?

The term “pH” refers to the measure of how acidic or basic (alkaline) a substance is on a scale from 0 to 14. It is described by Hopkins and Sharma in "Physiology, Acid Base Balance" as critical for assessing acid-base balance in bodily fluids. A pH of 7 is neutral, below 7 is acidic, and above 7 is basic or alkaline. The pH scale is logarithmic, meaning each number represents a tenfold change. For example, a substance with a pH of 4 is ten times more acidic than one with a pH of 5. A lower pH indicates more hydrogen ions and higher acidity, while a higher pH indicates fewer hydrogen ions and higher alkalinity. The term pH means "potential" or "power of hydrogen," with the "p" likely from French "puissance," German "Potenz," or Danish "potens," all meaning "power." Danish chemist Søren Sørensen introduced the concept of pH in 1909.

What is the pH of Coffee?

The pH of black coffee typically ranges from 4.85 to 5.4, making it mildly acidic. Some studies report the actual pH of coffee can reach up to 5.7 or higher, depending on bean type and brewing method. For example, a 2018 study published in Scientific Reports by Niny Z Rao of Thomas Jefferson University showed hot black coffee has a pH of 4.85 to 5.13, while cold brew is less acidic with a pH of 5.40 to 5.63. Interestingly, a 2013 study published in European Food Research and Technology by Alexia N. Gloess found pH values of coffee ranged from 5.5 to 5.9 across several brew methods. French press coffee had the highest pH, while single-serve capsules had the lowest.

The pH of coffee is measured using pH test strips or a digital pH meter. The process involves brewing the coffee, allowing it to cool to room temperature, and then dipping the strip or inserting the meter into the liquid. The resulting pH value is compared to a pH scale. Different types of coffee have different pH levels. Decaf coffee is typically 5.0 to 5.1 on the pH scale, mushroom coffee is less acidic than regular coffee, and instant black coffee is 4.9 to 5.5.

How Does pH of Coffee Compare to Other Beverages?

Coffee has a pH of 4.85 to 5.4, making it moderately acidic. Soda is far more acidic with a pH around 2.5. Black tea is similar to coffee with a pH of 4.9 to 5.5. Lemon juice (pH ~2.0), apple juice (pH 3.3–4.0), and energy drinks (pH 3.0–4.0) are more acidic than coffee. Chai tea is usually slightly less acidic than coffee, depending on how it's made. The following table compares the approximate pH ranges and relative acidity of common beverages.

What Factors Affect the pH of Coffee?

Factors that affect the pH of coffee are the elements that influence how acidic or basic it is. Key factors include bean type, roast level, coffee to water ratio, water quality, and brewing method. These factors can lower or raise the pH, changing the coffee’s taste and acidity level.

• Coffee Bean Type: The type of coffee beans plays a role in how acidic coffee is and its pH level. A 2007 study published in the Journal of the Science of Food and Agriculture by Susana Andueza found that Arabica coffees tended to have lower pH values (5.2 to 5.8), indicating higher acidity, compared to Robusta blends when brewed as espresso under same conditions.
• Roast Level: A 2009 study from University of California found that roasting coffee above 200°C reduces acidity, brightness, and body while increasing pH. Green beans contain 61–86 mg/g of chlorogenic acids, but roasting at 230°C for 12 minutes cuts them in half, and 250°C for 21 minutes nearly eliminates them. As acids break down, pH rises from 4.9 in light roasts to 5.3 in dark roasts.
• Coffee-to-Water Ratio: A higher water-to-coffee ratio typically results in a less concentrated brew, which can slightly affect the pH. According to a 2013 research in European Food Research and Technology by Alexia N. Gloess, lungo brews had a pH of 5.1 versus 4.8 for ristretto, confirming that more water slightly increases pH by diluting hydrogen ions.
• Water Quality: A 2021 study in Food Chemistry by Córdoba et al. shows water quality affects coffee pH. It finds brewing methods and water composition alter the pH of brewed coffee. It reports coffee brewed with different water types has varying pH levels due to mineral content like calcium and magnesium. It concludes water with higher mineral content increases coffee pH, making it less acidic.

What is Coffee Acidity?

Coffee acidity refers to the bright, tangy, or crisp flavor notes in coffee, not its pH level. It results from natural acids like citric, malic, and chlorogenic acids found in the beans. According to a 1985 study published in Zeitschrift für Lebensmittel-Untersuchung und Forschung, out of 22 acids contributing to coffee acidity, the primary ones are citric acid (12.2% in roast coffee), acetic acid (11.2%), and chlorogenic acids (9%).

Coffee acidity varies by origin, roast, bean type, grind size, and brewing style. High-altitude Arabica coffees from Ethiopia, Kenya, and Costa Rica and light roasts have higher perceived acidity and a sour, crisp flavor. Low-altitude Robusta coffees like those from Brazil and Indonesia have lower acidity. Processing methods affect acidity in coffee, with wet processing producing clean, bright cups with higher acidity, while wet hulling yields fuller-bodied, earthier brews with lower acidity. Coffee acidity is a key factor in evaluating coffee and serves as a primary metric used by experts and judges to score quality.

What Does Acidic Coffee Taste Like?

Acidic coffee tastes bright, tangy, and citrusy, with notes like lemon, green apple, or berries. The bright feeling is called perceived acidity and comes from the acids and flavors in coffee, not its pH. How acidic coffee tastes depends on the total amount of acid in it (titratable acidity) and the kinds of acids pulled out, which change based on how you brew and what equipment you use. More total acid makes coffee taste brighter, while less acid makes it taste smoother.

What Makes Coffee Acidic?

Coffee is acidic because it contains organic acids like citric, malic, quinic, acetic, formic, lactic, chlorogenic (CGAs), and tartaric acid. These compounds collectively contribute to the enhanced acidic profile observed in caffeinated and decaffeinated coffee.

• Citric Acid: Citric acid is a key acid in green coffee, adding bright, fruity acidity. Arabica has more citric acid than Robusta, but levels drop during roasting. A 2019 study in Royal Society of Chemistry found green Arabica can reach up to 1.3 g/kg of citric acid.
• Malic Acid: Malic acid is a key acid in green coffee, known for adding a smooth, apple-like tartness, as per a 1999 study in Chemistry and Environmental Science. Similar to citric acid, its concentration decreases with roasting. Green Arabica coffee has around 1.2 g/kg of malic acid, but roasting can reduce this to below 0.5 g/kg, impacting the perceived acidity, as noted by Michael Ginz in a 2000 study published in the European Food Research and Technology.
• Chlorogenic Acids (CGAs): Chlorogenic acid is a group of polyphenol compounds, and particularly 5-caffeoylquinic acid (5-CQA), are abundant in green coffee beans. During roasting, these CGAs degrade into various compounds, including quinic and caffeic acids, which contribute to the coffee's complex acidic and bitter profile. Arabica coffee, for example, can contain up to 8 g/kg of 5-CQA in its green beans, but this amount is significantly reduced during roasting (Vignoli et al., 2014).
• Quinic Acid: Quinic acid refers to an organic acid found in coffee beans that contributes to the bitterness and astringency of the brew. Quinic acid levels increase significantly during the roasting process, particularly in darker roasts, due to the breakdown of chlorogenic acids. This increase in quinic acid not only enhances the perceived bitterness but also contributes to the complex flavor profile of the coffee, adding depth and astringency.
• Acetic Acid: Acetic acid is a byproduct of the roasting process, which, according to a 2008 study in the Journal of Agricultural and Food Chemistry, contributes to a vinegar-like sourness and a pungent aroma. Dark roasted Robusta coffee can contain up to 10 times more acetic acid than green coffee, with concentrations exceeding 2.0 g/kg, as per 200 study by Michael Ginz published in European Food Research and Technology. This significant increase is due to the breakdown of carbohydrates like sucrose during roasting.
• Formic Acid: Formic acid is a naturally occurring organic acid, and although present in smaller amounts in coffee, adds a sharp, pungent sourness to coffee, as noted by Pam Hartwig in a 2006 study published in the Journal of Food Science. Formic acid levels are notably higher in Robusta coffee, particularly after roasting, with dark roasts containing up to 0.5 g/kg. This acid forms primarily through the degradation of sugars and other organic compounds during high-temperature roasting.
• Lactic Acid: Lactic acid occurs naturally in coffee beans and is less reduced by roasting than other acids. A 1995 study in the Journal of Food Science titled "Flavor Characteristics of Lactic, Malic, Citric, and Acetic Acids at Various pH Levels" found it maintains stable levels, adding smoothness and mild acidity to brewed coffee. In green and roasted Arabica coffee, lactic acid remains stable at 0.3 to 0.4 g/kg. USDA researchers note this consistency helps balance acidity and mouthfeel, making it essential to coffee’s flavor profile.
• Tartaric Acid: Tartaric acid is a naturally occurring organic acid that is present in many fruits, most notably grapes, and is present in lower concentrations, adds a sour taste and enhances fruit flavors in coffee, according to experts at The Good Scents Company Information System. In green Robusta coffee, tartaric acid levels are about 0.2 g/kg, which generally decreases slightly after roasting as per a 1999 study in Chemistry and Environmental Science. This acid plays a subtle role in the overall flavor enhancement, particularly in fruity coffee profiles.

What Health Effects Does Coffee Acidity Have?

Coffee acidity has both positive and negative health effects. On the positive side, natural acids like chlorogenic acid provide antioxidants that may reduce inflammation and protect cells. A 2023 study published in International Journal of Molecular Sciences by Giuliana La Rosa showed that chlorogenic acid is a strong antioxidant that lowers harmful molecules (ROS and MDA) inside cells. It also reduces inflammation by blocking signals like IL-1β and TNF-α, which helps keep cells healthy. On the downside, high acidity can irritate the stomach, worsen acid reflux, and harm dental health. For those with gastritis, reflux, or IBS, brewed coffee’s acidity may cause discomfort and health problems.

Does Coffee Make Your Body Acidic?

No, coffee does not make your body acidic. Although coffee has a low pH, it does not cause acidosis or disrupt your pH balance. Your body maintains a tightly regulated blood pH between 7.35 and 7.45 through buffering systems. The acids in coffee do not significantly alter your body's overall pH balance or cause systemic acidity. While coffee can make your urine a little more acidic, this effect is small and temporary. The body regulates urine pH through kidney function, so coffee alone is unlikely to cause significant or harmful acidity in urine.

How to Make Coffee Less Acidic?

To make coffee less acidic, follow these seven steps below.

1. Choose Dark Roast Coffee
2. Use Robusta Coffee Beans
3. Brew at Lower Temperatures
4. Reduce Brewing Time
5. Adjust Coffee-to-Water Ratio
6. Use a Coarser Grind
7. Add Milk or Cream

1. Choose Dark Roast Coffee

Choose dark roast coffee instead of medium or light roasts to reduce acidity. Dark roasts are roasted for 12–20 minutes at 425 °F to 455 °F; they have a darker color, lower acidity, and a bold, bittersweet flavor. A 2023 study published in Current Research in Food Science by Christina J. Birke Rune found that citric, malic, and chlorogenic acids decreased as roast level darkened from light to dark. A 2024 study published in Scientific Reports by Laudia Anokye-Bempah found total titratable acidity of coffee peaks at first crack, then returns to baseline by second crack. To make less acidic coffee, choose dark roasts like Full City+, Vienna, French, or Italian, which roast beyond second crack and taste less sharp than City or Medium roasts.

2. Use Robusta Coffee Beans

Use Robusta coffee beans to make coffee less acidic because they contain lower levels of acidic compounds than Arabica beans. A 2011 study by Natalina Bicho published in the International Journal of Food Sciences and Nutrition found Arabica beans consistently have more chlorogenic acid than Robusta, even though roasting reduces levels in both. Robusta also contains less citric acid and produces a milder acid flavor. A 2013 study in Ecology of Food and Nutrition by researchers from the Department of Biomass Science and Technology at New University of Lisbon found Arabica coffee has 109% more citric acid and stronger acid flavor than Robusta. Robusta scored 1.28–2.71 in acid flavor, while Arabica scored 2.92–5.42. These differences make Robusta a better choice for low-acid coffee.

3. Brew at Lower Temperatures

Brew coffee at lower temperatures to reduce acidity, as cooler water extracts fewer acidic compounds. A 2022 study by Mackenzie E. Batali from the Department of Food Science and Technology at the University of California show that cold brews, brewed around 4°C (39°F), have higher pH levels and lower titratable acidity than hot brews, resulting in a smoother, less acidic taste. A 2019 study by Giulia Angeloni of the University of Florence confirmed cold brew has lower titratable acidity, higher sweetness, and reduced sourness. Heating cold brew doesn’t increase acidity. Cold brewing extracts fewer acidic compounds, and warming it later doesn’t alter its chemistry.

4. Reduce Brewing Time

Reduce brewing time to make coffee less acidic because longer steeping increases the extraction of chlorogenic acids (CGAs), which cause acidity. Shorter contact between water and coffee grounds limits CGA release. A 2014 study by Iziar A. Ludwig from the University of Glasgow showed that over-extraction led to more CGAs in both light and dark roasts. For example, light roast over-extracted with 55 mL of water had 306 mg of CGAs versus 244 mg with standard extraction using 35 mL of water. The study also found that espresso acidity varied across countries due to differences in volume and preparation methods.

5. Adjust Coffee-to-Water Ratio

Adjusting the coffee-to-water ratio makes coffee less acidic by reducing the concentration of extracted acids. A higher ratio (more coffee, less water) usually leads to a stronger and more acidic brew. A 2007 study by Susana Andueza from Food Science and Technology, and Toxicology Department at the University of Navarra found that increasing the coffee dose from 6.5 g per 40 ml to 8.5 g per 40 ml raised the perceived acidity in espresso. A 2023 study by Agnese Santanatoglia et al. showed that lower ratios produced less acidic coffee across multiple brewing methods. For instance, French Press (1:14) and Filter (1:16.6) were less acidic than the V60 method (1:15). Lower ratios dilute acidic compounds and result in a smoother cup.

6. Use a Coarser Grind

Using a coarser grind makes coffee less acidic because it reduces the surface area exposed to water during brewing. Less surface area slows extraction and limit the release of acidic compounds like chlorogenic acids. A 2019 study by Nancy Cordoba from Universidad de La Sabana found coarse grinds produced coffee with lower titratable acidity, while medium grinds extracted more chlorogenic acids and increased acidity in less time.

7. Add Milk or Cream

Adding dairy-based milk or cream to coffee does make it less acidic. Milk and cream help balance the pH level of coffee by diluting the acidity and acting as a buffer due to their protein and calcium content. According to a 2021 study in Foods by Tugce Aydogdu, raw cow’s milk has a pH between 6.7 and 6.9 because its casein micelles, amino acids, and dissolved minerals regulate hydrogen-ion activity. When added to coffee, these buffering components raise the overall pH and smooth out the brew’s sourness. This makes milk-based coffee drinks like cappuccino, latte, and cortado gentler on acid-sensitive stomachs.

What is the Least Acidic Coffee?

The least acidic coffee is a dark roast Robusta blend. Robusta beans have fewer organic acids than Arabica. Dark roasting (Full City or darker) lowers acidity by breaking down chlorogenic acids. Low-altitude beans are also less acidic. Natural processing and older roast dates further mellow the acidity for a smoother cup.

The least acidic coffee typically comes from regions like Brazil, Sumatra, and other parts of Indonesia. These coffees grow at low elevations and have fuller bodies with muted acidity. Brazilian and Sumatran beans offer smooth, earthy flavors and naturally low acidity. Look for specialty coffee brands like Colipse that roast these beans to a medium-dark level and deliver them fresh to ensure you get a consistently low-acid, rich cup every time.

Where to Buy the Least Acidic Coffee Beans?

You can buy the least acidic coffee beans at specialty coffee shops, online retailers like Amazon, or even health food stores like Whole Foods. The prime example is Colipse Coffee, an online store offering low acid coffee blends and single-origin options like Sumatra, Brazil, and Bali, starting from from $20.99 USD for 12 oz bag. Choose from decaf, espresso, and cold brew roasts available in whole bean or ground form in coarse, medium and fine suitable for many brewing methods. At Colipse, we provide free U.S. shipping, multi-bag discounts, and flexible subscriptions.

What are the Best Low Acid Coffee Brands?

The best eleven low acid coffee brands are listed below.

• Colipse Coffee
• Lifeboost Coffee
• Puroast Low Acid Coffee
• Tyler’s No Acid Organic Coffee
• Volcanica Low Acid Coffee
• HealthWise Low Acid Coffee
• Simpatico Low Acid Coffee
• Tieman’s Fusion Coffee
• Java Planet Low Acid Coffee
• Fabula Low Acid Coffee
• Lucy Jo’s Coffee Mellow Belly

What are the Best Brewing Methods to Make Acid Coffee?

The best brewing methods to make low acid coffee are listed below.

• Cold Brew: Cold brew coffee is made by steeping coffee grounds in cold water for 12-24 hours, which slows the extraction of acidic compounds and oils.
• French Press: The French press method uses coarsely ground coffee steeped in hot water for a few minutes, which allows for controlled extraction of flavors while minimizing over-extraction of acidic compounds.
• AeroPress: AeroPress uses a short steep time and gentle pressure to extract coffee, which reduces the extraction of harsh acids and bitterness.
• Espresso: Espresso brewing uses high pressure and a short extraction time, which extracts a concentrated coffee shot with a balanced acidity profile.

Which Coffee Drinks Have the Lowest Acidity?

The following list shows coffee drinks with the lowest acidity.

• Cold Brew Coffee
• Nitro Cold Brew
• Espresso
• Americano
• Latte
• Cappuccino
• Flat White
• Bulletproof Coffee

Is Iced Coffee Less Acidic?

Yes, iced coffee is generally less acidic than hot coffee. The cold brewing process reduces acid levels by extracting fewer bitter compounds. This lower acidity makes iced coffee easier on the stomach and teeth, especially for people sensitive to acid.

Is Organic Coffee Less Acidic?

No, organic coffee is not always less acidic than regular coffee. Acidity depends more on bean type, roast level, and brewing method than on whether it's organic. However, organic beans grown at lower altitudes or roasted dark may produce a smoother, less acidic taste.

Are Used Coffee Grounds Acidic?

Used coffee grounds are only mildly acidic to nearly neutral, with a typical pH of 6.5–6.8 after brewing. While fresh coffee grounds are more acidic, used grounds do not significantly acidify soil and their effect on soil pH is minimal and temporary. Therefore, used coffee grounds are not acidic enough to meaningfully alter soil pH for most plants.