Coffee Brewing

12.1.1 Definition of Extraction Extraction is a mass transfer process in which specific components are selectively separated and transported between substances of different phases. It generally occurs through interactions between phases such as solid–liquid or gas–liquid systems. Coffee extraction is a representative example of a solid–liquid extraction process. The target substance to be extracted is […]

Water as the Defining Variable in Coffee Filter Manufacturing When manufacturing coffee filters—more precisely, when producing the paper used for filters—what is the most important factor? The primary raw material, wood pulp, is of course important. Depending on the type of pulp, fiber length and strength vary, which in turn can influence the thickness of

Paper filters for coffee extraction are generally available in two color categories: white and yellow-brown. Their coloration is closely associated with whether they undergo a bleaching process. However, beyond the mere change in appearance, bleaching introduces a number of chemical and physical differences that meaningfully influence extraction behavior. In modern manufacturing, both white and brown

The Impact of Dissolved Minerals on Coffee Flavor Water purification refers to the process of removing impurities from raw water through sedimentation, filtration, and other treatments, in order to produce water that meets safety and quality standards. The sources from which water is drawn are called intake sources or water reservoirs. In Korea, there are

The Impact of Dissolved Minerals on Coffee Flavor Dissolved minerals commonly found in water include cations such as calcium (Ca²⁺), magnesium (Mg²⁺), sodium (Na⁺), potassium (K⁺), and hydrogen (H⁺), and anions such as bicarbonate (HCO₃⁻), chloride (Cl⁻), sulfate (SO₄²⁻), nitrate (NO₃⁻), and hydroxide (OH⁻). Among these, the ions most relevant to coffee extraction and sensory

Hydrogen Ion Concentration (pH) In simple terms, pH refers to the concentration of hydrogen ions (H⁺) in an aqueous solution. Although the term “hydrogen ion” is commonly used, free hydrogen ions are highly reactive in water and do not exist in isolation. Instead, they bind with water molecules to form hydronium ions (H₃O⁺). Thus, pH

Alkalinity Alkalinity refers to the water’s capacity to neutralize acid (H⁺). While pH indicates the current chemical condition of a solution, alkalinity represents how well that solution can resist changes in pH when acid is introduced. For this reason, alkalinity is often described as buffering capacity. The primary contributors to alkalinity are bicarbonate ions (HCO₃⁻),

Definition of Hardness To understand hardness, we should first ask why the concept was created. Hardness emerged around the late 19th to early 20th century. During the Industrial Revolution, boilers and steam engines suffered explosions as scale accumulated, and everyday problems arose because soap would not dissolve properly in water. The cause was traced to

Until the 2020s, the importance of water in coffee brewing was rarely emphasized. Many people overlooked its significance. However, as the specialty coffee industry entered the 2020s, an increasing number of professionals began to stress the critical role of water. This shift occurred because many had experienced firsthand how the chemical composition of water profoundly