Although arabica and robusta coffee may appear similar in appearance – there are a number of differences that significantly differentiate these two popular varieties of coffee. The following list points out a few basic differences.
Growing Conditions
The arabica coffee shrub typically grows between 2.5-4.5 meters in height, requires a temperature between 15°-24°C and an annual rainfall of about 1200-2200 mm/yr. Whereas robusta grows slightly taller 4.5-6.5 meters, requires a warmer temperatures of 18°-36°C and slightly more rainfall (2200-3000 mm/yr) than arabica. Arabica typically also yields less coffee per hectare than robusta – meaning higher costs in production.
Bean Shape
Arabica coffee beans have a slightly larger/elliptical shape than the smaller, more round robusta beans. Structural differences also exist between the beans, which may explain why both beans roast differently under identical conditions.
Caffeine and Chlorogenic Acid
Both caffeine and chlorogenic acid (CGA) have been documented as potential insect deterrents and chemisterilants. Arabica generally has less caffeine and chlorogenic acid than robusta.
Lipid and Sugar Content
Arabica contains almost 60% more lipids and almost twice the concentration of sugars than robusta. Increased levels of sugars in coffee play an important role as its decomposition during roasting increase the level of perceived acidity and dissolved solubles in coffee.
Pollination
Arabica is self-pollinating plant, meaning the plant will have fewer mutations and fewer variations throughout its life cycle as compared to Robusta.
Chromosomes
Arabica has double the number of chromosomes at 44 than robusta at 22.
Uses of Arabica and Robusta
Each of these characteristics suggests that arabica is the better species, and in many ways it is. Robusta has its place in the coffee-drinking world.
Because of the price factor, almost all instant coffee are made from robusta beans.Robusta sells for less than arabica, because it is less fragile and has a longer harvest season. Moreover, Robusta yields more per hectacre as compared to Arabica. Robusta been being a hybrid variety is more resistant to rust disease and as such no need for spraying insecticides or pesticides, as compared to Arabica variety. Therefore, the cost of production of Robusta works out much lesser than Arabica because of yield factor on one hand and cost of cultivation aspect on the other.
Robusta is also used in some of the most revered espresso – Italian espresso. When brewed using an espresso machine, robusta coffees produce a plentifu of thick crema. Roasters in the United States have been known to use high-quality robustas in their espresso blends, but Italian espresso is especially well-known for its crema.
Today, arabica is the predominant species used in the U.S. In fact, almost all the coffee Americans drink today is from arabica beans. Part of this reflects Americans’ distaste for instant coffee. The trend has also been brought about by the gourmet-coffee movement of the past 30 years. Not long ago, robusta accounted for a large portion of the coffee drunk in the U.S. Now, international coffee companies’ have followed the lead of small roasters and transitioned to mostly Arabica coffee.