In Specialty Coffee, we talk a lot about acidity. But what are we referring to and how does this benefit the industry and our customers?
Acidity is what contributes to the liveliness, brightness, excitement, body, texture and complexity of a coffee. When you take a sip it’s what makes you mouth water and invites you to take another. The absence of acidity flatlines our drinking experience and limits its biological and crafted uniqueness. What is your favorite coffee and why? Chances are you found your match because of the varying levels and balance of acids working together to elucidate flavors like apples, berries, watermelon, cotton candy, honey, jasmine, peach, bergamot, etc. Farming, processing, roasting and brewing all play a role in how a coffee expresses itself through acidity.
Let’s take a look at a few acids we commonly experience in drinking a cup of coffee.
Citric - plays a role in the metabolic system of coffee. The presence and quality of citric acid can be linked to the quality and skill of a producer. Roasting diminishes the concentration of citric acid over temperature and time. Light roasted coffee will have a higher concentration of citric acid in the cup while darker roasts will have less.
Flavor associations: lemons, oranges, limes, strawberries, raspberries, tomatoes, sourdough bread
Malic - similar to citric acid in that it plays a role in the metabolic system of the coffee tree. Roasting diminishes the amount of malic acid as well. Think of malic acid as being a large contributor to the “fruitiness” of a brewed coffees flavor profile.
Flavor associations: apples, watermelon, bananas, apricots, pears, peaches, rhubarb, tomatoes, peas, carrots
Acetic - Unlike citric and malic acid, acetic acid is created through processing and roasting. It is known to contribute to a “clean” cup when at right levels but can also contribute negative flavors like vinegar or over fermentation when out of balance.
Flavor associations: wine, cider, vinegar, pickled foods, kombucha
Tartaric - Naturally found in coffee fruit but has lower levels when compared to citric and malic acid.
Flavor associations: grapes, cranberries, apricots, tamarind
Phosphoric - Imparts a sparkling sensation on your tongue. An inorganic acid often introduced to coffee via soil composition and fertilization. Phosphoric acid does not have any flavor but when combined with other acids may contribute to flavors like blackberries and currant.
Lactic - Formed during the fermentation of food. Contributes to mouthfeel and texture.
Flavor associations: yogurt, kefir, sourdough bread
Acidity is a sensory experience. The combination of various acids, sugars and other volatile compounds are what gives a coffee its particular flavor. Understanding the chemical composition of a coffee can help us to lock in and find those flavor associations to relate to one another about how amazing specialty coffee is! It keeps us engaged, always looking forward to the endless culinary possibilities and backwards to those moments we have shared with one another and drank a truly memorable coffee. Thank you acidity! You’re the best!