Drip Brew Coffee: A Widely Used Method of Coffee Brewing

Drip brewing, or filtered coffee, is a method for brewing coffee which involves pouring water over roasted, ground coffee beans contained in a filter. Water seeps through the coffee, absorbing its oils and essences, solely under gravity, then passes through the bottom of the filter. The used coffee grounds are retained in the filter with the liquid falling (dripping) into a collecting vessel such as a carafe or pot.

Paper filters (invented in Germany by Melitta Bentz in 1908) are commonly used for drip brew all over the world. One benefit of paper filters is that the used grounds and the filter may be disposed of together, without a need to clean the filter. However, metal filters are also common, especially in India. These are made of thin perforated metal sheets that restrain the grounds but allow the coffee to pass, thus eliminating the need to have to purchase separate filters which sometimes cannot be found in some parts of the world. Additionally, many machines now use permanent plastic filters, which are made of a fine mesh. These of course add to the maintenance of the machine, but reduce overall cost and produce less waste.

Drip brewing is a widely used method of coffee brewing, particularly in North America owing to the popularity of domestic coffeemakers. There are, however, several manual drip-brewing devices on the market, offering a little more control over brewing parameters than automatic machines. One example is the Clever Coffee Dripper, which has a patented stopper valve, allowing the user to control steeping time and the proportion of coffee to water. The device is popular amongst baristas at respected coffee bars like San Francisco's Four Barrel Coffee, New York's Gimme Coffee! and D.C.'s Chinatown Coffee. There also exist small, portable, single serving drip brew makers that only hold the filter and rest on top of a cup. Hot water is poured in and drips directly into the cup.

Brewing with a paper filter produces clear, light-bodied coffee, which is free of sediments, although lacking in some of coffee's oils and essences, which are trapped in the paper filter. Among these are certain diterpenes that appear to increase risk of coronary heart disease. Metal filters do not remove these components. [source : Drip Brewed Coffee]

The Advantages of Instant Coffee

Instant coffee, also called soluble coffee and coffee powder, is a beverage derived from brewed coffee beans. Instant coffee is commercially prepared by either freeze-drying or spray drying, after which it can be rehydrated. At least one brand of instant coffee is also available in concentrated liquid form.

Instant coffee was invented in 1901 by Satori Kato, a Japanese scientist working in Chicago. Kato introduced the powdered substance in Buffalo, New York, at the Pan-American Exposition. George Constant Louis Washington developed his own instant coffee process shortly thereafter, and first marketed it commercially (~1910). The Nescafé brand, which introduced a more advanced coffee refining process, was launched in 1938.

Advantages of instant coffee include speed of preparation (instant coffee dissolves instantly in hot water), lower shipping weight and volume than beans or ground coffee (to prepare the same amount of beverage), and long shelf life, though instant coffee can also spoil if not kept dry.

Instant coffee is available in powder or granulated form contained in glass jars, sachets or tins. The user controls the strength of the resulting product, by adding more or less water (for a weaker or stronger brew). Instant coffee is also convenient for preparing iced coffee like the Greek frappé, which is popular in warmer climates and hot seasons. In some European countries such as Spain and India, instant coffee is commonly mixed with hot milk instead of boiling water.

In commercial processes the decaffeination of instant coffee almost always happens before the critical roasting process which will determine the coffee's flavour and aroma processes. Compared to overall health effects of coffee, instant coffee appears to be as efficient as filtered coffee in decreasing the risk of diabetes type 2.

Instant coffee is one of the ingredients in "Caffenol-C", a home-made, non-toxic black-and-white photographic developer. The other ingredients in the basic formula are ascorbic acid and anhydrous sodium carbonate; some recipes also include potassium bromide as a fog-reducing agent. The active ingredient appears to be caffeic acid. Initial experiments on Caffenol were performed in 1995 at the Rochester Institute of Technology; addition of ascorbic acid began around 2000, yielding the improved Caffenol-C, which is less likely to stain negatives than the original formulation. Experiments have shown that cheaper, less desirable brands of coffee work better for this application than more expensive brands. [source : Instant Coffee]

Different Types of Coffee

Regardless of coffee’s origins, all beans go through a similar process in preparation for brewing. trees reach maturity between three and four years when their clusters of fruit turn deep red. Farmers pluck the ripe cherries by hand and transport the full baskets by mule or truck to the processing plant. Since the coffee bean is the seed inside the sweet cherries, the fruit is forced through a manual machine to extract the seeds. While the pulp is salvaged for use as fertilizer, the seeds – or coffee beans – are soaked in cool water to stimulate a fermentation process. Next the beans are spread over mats to dry in the open sun. Rotten or disfigured beans are removed so only the highest quality coffee beans remain. Next the thick, parchment-like hull is removed to reveal a coffeebean. 

There are several species of coffee trees but most commercial growers use primarily the Arabica and Robusta species. trees are believed to produce the highest quality . However, Robusta trees are more economically viable due to their heartiness. Coffees are rarely designated as Robusta or Arabica . The soil and environmental conditions play such a significant role in flavoring the beans, that all coffee beans are labeled according to their geographic origins. Kilimanjaro coffee comes from the Tanzanian foothills near Mount Kilimanjaro, for example, while Java coffee derives from the Indonesian islands. 

Coffee roasting process

For many years, consumers purchased green coffee beans and roasted them at home. Today nearly all beans are roasted by the manufacturers who possess the appropriate equipment. Roasting the beans enhances the coffee’s flavor and releases pungent oils. Although there exist no strict conventions for classifying different types of roasts, there are some well-known roasts that have maintained a certain consistency between manufacturers. American roast produces a medium bodied coffee. This roast is used almost exclusively in average American store brands and in restaurants across the country. Brazilian roast is a slightly darker roast than the American roast. Despite its name, the roast has no connection to Brazil. An increasingly popular roast is the French roast. French roasted beans are the color of dark chocolate. The roast produces a deep, hearty brew and a touch of the bean oil should be visible on the coffee’s surface. The darkest roast is Espresso. Beans are roasted until they are nearly burnt which gives the roast its distinct, sharp flavor. 

Coffee grinder

All coffee is best bought as whole roasted beans. The minute the beans have been ground their flavor diminishes. Whole beans can be frozen for several months, but ground beans will last in an airtight container no longer than a few weeks. Coffee is brewed by two methods: decoction or infusion. Decoction refers to boiling the beans until the flavor is released. This method was popular before coffee machines but is now only reserved for traditional Turkish coffees. The most popular means of brewing coffee is by infusion. Infusion includes steeping coffee grounds in hot water or filtering the grounds with hot water through paper or cloth. The ideal cup of coffee depends upon one’s preference, but the standard ratio is two tablespoons of coffee grounds to three-quarters a cup of water. Brewed coffee must be served immediately as oxidation will ruin the flavor.

Many coffee drinks have become popular with Americans in recent years. Espresso, made by brewing espresso roasted beans under high pressure, is a strong, black coffee served in small cups. Machiatto is espresso with a touch of steamed milk. Cappuccino is even thirds of espresso, steamed milk, and a ‘cap’ of milk foam. Café latte is one-third espresso and two-thirds steamed milk. The favorite French drink, Café au Lait is made with strong coffee (never espresso) and generous portions of hot milk. Flavored coffee -- such as hazelnut, maple walnut and raspberry -- is produced by adding flavored oils to the beans during roasting. Depending on the manufacturer, the flavors can be natural or artificial. 

Coffee connoisseurs rate coffees based on their aroma, acidity (liveliness), body and flavor. High quality coffees have strong, fragrant aromas. High acidity levels in beans is preferable, but their body can range from light (Mexican coffees) to heavy (Sumatra coffees). Connoisseurs describe the flavor using adjectives such as earthy, mellow or grassy. Although your average coffee consumer in America could not distinguish an earthy flavor from a mellow one, the busy neighborhood Starbucks is evidence enough that Americans love all varieties of coffee regardless.

[source : Coffees]