Instant Coffee
There is no doubt that instant coffee is inferior to freshly made “real” coffee. The aroma and flavour are very different. The only thing that can be said in favour of instant coffee is that it is convenient and better than poorly made ground coffee. It is also easy to add to recipes that require coffee.
Most instant coffee is made from blends of low or medium grade robusta coffee beans although some upmarket instant coffee brands are made from arabica coffee beans.
Instant coffee powder or granules are made by brewing the coffee in large vats and then removing the water. The budget brands of instant coffee are spray-dried to remove the water resulting in a fine powder. The better quality instant coffee brands are freeze dried to produce coffee granules.
Freeze drying is a process whereby the coffee is frozen to below its triple point – the temperature at which the three phases (solid, liquid and gas) can co-exist. The pressure is then reduced and enough heat supplied so that the water sublimes, i.e., it goes directly from a solid to a gas. The coffee granules are then packed for sale.
De-caffeinated Coffee
Caffeine is probably the most widely consumed drug in the world. It is said that if coffee was discovered today you would need a prescription to purchase it. In small doses it can increase alertness but taken in larger doses it can cause problems such as insomnia and heart palpitations.
The better quality coffee beans contain less caffeine than the robusta beans which are the beans used mostly for instant coffee. Due largely to the convenience of instant coffeee, its consumption has increased which means the average caffeine intake has increased.
There are three methods of decaffeinating coffee. ALl of these are done at the green coffee bean stage as the flavour of the coffee is mostly developed when the bean is roasted. Removing the caffeine at the green bean stage reduces the impact on the flavour and aroma.
Chemical Solvent: In this method the green beans are steam treated to dissolve the caffeine which is extracted by a chemical solvent under pressure. Traces of solvent in the beans are removed by further steaming the beans after which the beans are dried. Naturally, there are concerns about traces of solvent left in the beans.
Supercritical Gas: A supercritical gas is one which is maintained at a temperature and pressure where it exhibits characteristics of both liquid and gas.They can diffuse into and through solids like a gas but dissolve materials like a liquid. Supercritical carbon dioxide is applied to steamed green coffee beans to extract the caffeine. The caffeine is separated from the gas by rinsing or by absorption and the gas is recirculated.
Swiss Water Process: In this process the green beans are soaked in water. The extract from the beans is passed through activated charcoal to remove the caffeine. The beans are then semi-dried and the caffeine-free extract is added to them before they are fully dried and roasted.
After all the processing that instant coffee and decaffeinated coffee goes through, is it any wonder it doesn’t taste like real coffee?
