Glossary beginning with M

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A simple espresso drink: a shot of espresso with a small dollop of foamed milk on top.

Maillard Reaction

The Maillard reaction is a chemical reaction between an amino acid and a reducing sugar, induced by heat in the coffee roasting process. It results in the browning color of coffee (from melanoidins, which are key to espresso crema too), as well as many volatile aromatics and flavors. It is not unique to coffee, and is at work in a variety of food conversion or cooking operations: toasted bread, malted barley, roasted or seared meat, dried or condensed milk.

Malic Acid

Malic acid is yet another of the many acids that adds to favorable perceptions of cup quality; malic acid often adds apple-like flavors. In Kenya coffees, it reaches levels of 6.6 g/kg whereas robusta coffees measure about about one-third to one-half of that level.


A trade name used for wet-hulled Sumatra coffees. It is an area and a culture group as well (spelled Mandailing often) but there is little coffee production in this area anymore. Mandheling coffees might have originated from anywhere in North Sumatra or Aceh provinces. They are graded on flavor defects in a very loose way, so a "Grade One" Mandheling might, in fact, have many physical defects.

Manual Grinder

A burr grinder powered by hand-turning a crank. Manual grinders can be cheaper than their electric counterparts, and they produce comparable quality grinds, but since they require a fair amount of effort to operate, they are not for everyone. Finer grinds will require more revolutions of the crank, and so take more time and effort.


As the name indicates cross between large-bean Maragogype and Catuai cultivars. It has a larger than average bean and interesting cup flavors, similar to Pacamara.


As the name indicates cross between large-bean Maragogype and Caturra cultivars. It seems to be found most in Nicaragua, although I am not sure exactly why. It can be grown elsewhere, certainly. It has a larger than average bean and interesting cup flavors, similar to Pacamara.


Maragogype is a mutation of Typica coffee and was discovered in Brazil. The Maragogype is a large plant with big leaves, low production and very large fruits (and seeds / green beans). It has been called the "Elephant Bean coffee." Maragogype adapts best between 2,000-2,500 feet. The mild cup characteristics and bean size were historically sought-after in Europe. Roasting can be difficult (not to mention feeding it into grinder burrs!), but sometimes Maragos can be fantastic. It benefits from gentle warm-up in the roaster, and long, gentle roast times temperature profiles.


Meters Above Sea Level, altitude that is...


Also spelled M'buni or Buni, this is a Swahili term that refers to dry-process coffee. In Kenya, M'buni coffees are harvested at the end of the season and sell for much less than red rip cherry from the middle of the season, which are wet-processed.

Mechanical Dryer

Mechanical dryers are used as an alternative to sun-drying coffee on a patio, either due to poor weather, or when the patio does not have enough capacity. It is not considered as good as sun-drying coffee. The drum type dryer, called a Guardiola, is considered better than the vertical dryers.


A defective flavor characterized by a penetrating medicine-like, alcohol or chemical type taint flavor. This type of defect usually comes from poor processing or storage, but could indicate that the coffee has absorbed the smell of some industrial material: tainted jute bags, stored it plastic at high temperatures, etc.


A blend containing a coffee that has been roasted to a different levels (or steps) - light to dark.


Coffee that has been hanging out in the warehouse, but not really helping out with the work, just relaxing over in the corner, can be described as "mellow coffee". If the coffee gets up and stretches its legs every so often, it is still mellow. But if it starts to complain about being bored, it is no longer mellow.

Methylene Chloride Decaf

The Methylene Chloride decaf method is a solvent-based process for washing the caffeine out of coffee. Called MC decaf for short. MC decafs have been shown to leave insignificant trace amounts of solvent that are fully dispatched in the roast process.


A Bourbon cultivar variant from Rwanda and Burundi. Bourbon coffees are named for the island in the India Ocean where French colonists grew it.


Micro-Lot is a term ripe and ready to be abused. It already is. It's a term that designates not only a small volume of coffee, but a lot produced separately, discretely picked or processed to have special character. In other words, a Micro-lot should have been harvested from a particular cultivar, from a particular plot of land, from a particular band of altitude, processed in a separate way ...or a comination of these things. Ultimately, it is the result of some concerted effort to separate and carefully prepare a lot of coffee that will have special characteristics. If a large lot of, say 250 bags, is divided up into 25 bags lots and sold to small/medium roasters, that is NOT a Micro-Lot. It also implies some experimental or investigative input on behalf of the grower, the buyer or both working in relation with each other. Further, it implies cupping of lots and making qualitative selection, in an active relationship between farmer and buyer. Many lots sold in the trade as "Micro-lot" do not meet these standards, so it becomes a marketing word, as "natural" was in the '70s and '80s, used to imply a vaue to a product that it does not truly possess!


A Micro-Mill is a tiny low-volume, farm-specific coffee producer who their lots separate, mill it themselves, gaining total control of the process, and tuning it to yield the best possible flavors (and the best price!) In Costa Rica, farmers usually belonged to large cooperative mills, or simply harvested cherry and sold it to a big mill. Large estates might have complete processing facilities. Now farmers of modest size can craft small micro-lots with complete control on scaled-down equipment from Penagos or Pinhalense.


Micro-Region is more specific coffee-producing zone. For example, if the Country for a specific lot is Nicaragua, the region might be Nueva Segovia (a state as well), the Micro-Region might be Dipilto, and then perhaps a nearby city name would locate the coffee even further.


Off aroma and flavor that reminds one of a dank, moldy closet. This flavor can hint at a dangerous coffee mold and should not be consumed. Most common in Sumatra coffees that ship with a high moisture content, and industrial grade robusta coffees.


A coffee mill might mean a coffee grinder, but we usually use the term to refer to a coffee processing facility, either a Wet-Mill or a Dry Mill. A wet mill will be part of the wet-process, where coffee is pulped (peeled), fermented in concrete tanks, and then washed and dried. Then it is ready for the dry mill, which may or may not be at the same location. At the dry mill it is hulled out of the parchment skin that surrounds the green bean, classified by density and size, sometimes by color too, and bagged for export. A wet mill can be called a Washing Station or a Factory (Kenya) or a Beneficio Humido (as opposed to a Benificio Seco for a Dry Mill).


A flavor or aroma reminiscent of minerals, which can be a positive characteristic if it is a secondary flavor sensation. Salty coffees can be similar to minerally coffees. This is sometimes found in softer Brazils, but we have found it in high grown lots from Guatemala, Panama and other areas, when the coffee has good quality but is not sweet. There might be a relation between old coffee trees and this flavor as well.


A flavor hint of mint found in coffee, which could indicate a clean and brisk mint hint, or a more rustic dried mint. It might even suggest a medicinal mint note, but this would be clear from the context it is used within. Most often we would use it to indicate a mouth-refreshing, clean, positive quality.

Moka Pot

Moka Pot stovetop brewers produce a dense concentrated cup that's something between espresso and Turkish coffee. Coffee is placed into a filter between the lower chamber (that you fill with water) and the upper chamber that will contain the finished beverage after brewing. Since the water is forced through the cake of coffee by pressure, the process bears more resemblance to espresso extraction that infusion (gravity-based) brewing.


Mokha Yemeni type of coffee, both in terms of the family of cultivars planted there, and the general trade name. The alternate spellings are Mocca, Moka, Mocha. The name refers to the former coffee port on the Red Sea called Al Mahka, and all the spellings are derived from a phonetic interpretation of the Arabic pronunciation for this town. It is no longer a coffee port, and most Yemeni coffee ships from Hodeidah, also on the Red Sea. In terms of cultivar, all types of Mokha coffee are proved to come from Harar, Ethiopia or other areas on the Eastern side of the Rift Valley. Yemeni Mokha coffee is the first commercially planted "farms" (the coffee is grown on stone walled terraces) and the souce for what would become Typica and Bourbon cultivars. So all coffee comes from West Ethiopia and the Boma plateau of Sudan, then to Eastern Ethiopia and Harar via the slave trade route, then to Yemen, then to the rest of the world. Moka is an established cultivar as well, found in many ICO coffee research gardens and grown in some locales (such as Maui, Hawaii).

Monsooned Coffee

Monsooned coffees are stored in special warehouses until the Monsoon season comes around. The sides of the structure are opened and moist monsoon winds circulate around the coffee making it swell in size and take on a mellowed but aggressive, musty flavor. Our source for Monsooned Malabar is the Coehlo's Gold brand from the Silver Cloud Estate. In thier monsooning process, arabica coffee is spread on the floor of the special monsooning warehouse in Mangalore, raked and turned around by hand to enable them to soak in moisture of the humid winds. The monsooning process takes around 12 to 16 months of duration, where in the beans swell to twice their original size and turn into pale golden colour.Then there are additional hand-sortings to remove any coffee that did not expand properly, and the coffee is prepared for export. This is an extremely earthy, musty, pungent cup with a unique combination of caramelly finish and potent flavors. It is not for those who like a "clean" cup, or sweet coffees! By all standard definitions, this is a defective set of cup flavors. But Monsooned Malabar get's a free pass by the coffee censors because of cultural tradition, history, and the fact that (while it doesn't conform to the traditional ideas of good coffee) it is in it's own right a unique coffee flavor. It has some use in espresso blending with a preparation of longer drum roasting and resting (after roasting) of 3+ days. There are Italian espresso roasting companies that use this coffee in their "exotic" blend offering, along with 2-3 other non-monsooned arabicas to even out the cup and provide aroma and some sweetness ... for example Cafes Trottet. Even as a drip/infusion brew, the coffee mellows after 2 days and the cup is more balanced so resting is key to best cup results.


A major component in the flavor profile of a coffee, it is a tactile sensation in the mouth used in cupping. quite literally can refer to how a coffee feels in the mouth or its apparent texture. In cupping mouthfeel is scored at light City roast level but mouthfeel can be directly affected in other ways by roast level as well, brew strength, and proper resting of the coffee after roasting. That is, Espresso and Dark Roast coffees have noticeably different mouthfeel than the same coffees at lighter levels. Body is synonymous with mouthfeel, but the latter implies a wider range of possible qualities, whereas body traditionally implies viscosity only. Mouthfeel is perceived by the trigemenal receptors, nerve fibers that surround taste buds.


Indicating the fruity layer of the coffee cherry, between the outer skin and the parchment layer that surrounds the seed.

Mulling Spice

A spice mix for adding flavor and aroma to a warm beverage, apple cider or wine. This mix might include all or an assortment of the following; allspice, nutmeg, cloves, cinnamon, star anise and various dried fruit peels. Also see warming spices

Mundo Novo

Mundo Novo is a commercial coffee cultivar; a natural hybrid between "Sumatra" and Bourbon, originally grown in Brazil. In my experience, when some farmers and brokers refer to "Brazilian Bourbon coffees", they might mean Mundo Novo. It has a rounded seed form. The plant is strong and resistant to disease. Mundo Novo has a high production, but matures slightly later than other kinds of coffee. It does well between 1000-1200 MASL, which suits Brazil coffee altitudes, with an annual rainfall of 1,200-1,800 mm.


Also known as "Barbados sugar" or "moist sugar," it is very dark brown and slightly coarser and stickier than most brown sugars. Unlike most other brown sugars, which are made by adding molasses to refined white sugar, muscovado takes its flavor and color from its source, sugarcane juice. This is a flavor that can be found in the sweetness of dry-processed or pulp natural coffees, mostly.


Musty refers to an aroma and/or flavor that ranges from slight intensity to mildewy defect flavor. Unlike Mildew taint, musty can have a slight (VERY slight) positive connotation when it is extremely mild, and linked to foresty flavors in Indonesia coffees. It can also relate to the hidey, leathery flavors of dry-process Yemeni coffees. In any greater intensity, or in a coffee profile that should be clean, musty is NOT a positive quality.