of roast levels as it is almost impossible to achieve a consistent roast, however, some people like the resultant melange roast. The beans may also be roasted on the stove top. One classic method is to use open-top cookware such as a cast-iron skillet, a frying pan, or a wok, the beans constantly stirred to obtain an even degree of roasting. Another option is to use a stove-top popcorn maker such as a "Whirley Pop" or similar device with an integral crank and internal agitator system to keep the beans in motion as they roast. Constant cranking or stirring is required, as is plenty of ventilation. The hot-air popper is sometimes pressed into service as a coffee roaster, but such a light-duty appliance is not designed to withstand the longer heat cycle required by coffee beans. As a result, the hot-air popper used for coffee may fail from heat damage. This method of roasting produces somewhat less smoke than oven or stove-top but it still requires good ventilation. It also blows chaff off of the roasting beans, so cleaning up the scattered chaff is a consideration. If used indoors, the room may retain a smoky smell long afterward. Roasting outdoors is an option. After using any of the above methods, the roasted beans must be manually cooled. A common method is to shake or toss them in a metal colander for a few minutes. Specially designed electric coffee roasters have been available since the 1970s. These counter-top appliances automate the roasting process, including a cooling cycle at the end. Unlike hot-air poppers they are designed to withstand extended high temperature operation. Two main types exist: the fluid-bed or fluid-air roaster, and the drum roaster. The fluid-bed roaster heats the beans faster, retaining more of their desirable acidic flavor compounds. However, the resulting roasted bean is tougher, harder to grind, and less of it ends up as "mouth feel" or body in the coffee beverage. The drum roaster takes more time so the acidic compounds are less in evidence, having evaporated somewhat to yield a mellow-tasting beverage. The roasted bean is softer and easier to grind, and more of it contributes to the body of the beverage. One drawback of the electric roasting appliances is their small capacity: for fluid-bed, and somewhat more for drum roaster. They are also expensive. Another drawback is that most models emit smoke. No matter what