When you drink a cup of coffee, have your ever been curious about coffee flavor? This cup is smooth but that cup is more lighter or bitter? Um… the coffee aroma is not same too. Or are you bad skill? Not at all! (You and I are good. Dont blame yourself. lol)
There are several factors involved. The fact is type and processing of the coffee bean which you choose. By the way when I enjoy shopping coffee at supermarket. I read all coffee package to check the type of coffee bean before buying. So what’s else?…

Hello may I help you? Robusta or Arabica?
… Several questions are asked by coffee counter lady when I am standing in front of the big coffee self.
Coffee roasting? One question I pay attention to.
Home roasting or roasted coffee? Then she recommends some quality green coffee beans for home roasting and she show me many coffee roasting choices that she can sevice extraordinarily also.
Finally I buy coffee what I prefer.

Now thinking, maybe coffee roasting is one important thing what make different taste of coffee is. After the coffee harvesting and coffee processing, you got fresh green coffee beans. How can you brew coffee? One importent step before grinding, brewing. Well, you cannot consume the raw green coffee beans.
So getting to know the coffee roasting!

The coffee roasting is the process that changes the properties of fresh green coffee beans chemically and physically into roasted coffee beans. You will see changed characteristics: color, flavor, aroma, dryness and density. Yes, roasted coffee is what coffee drinkers perfer.

During roasting, first stage green coffee beans absorb the heat (Endothermic) become to slowly dry, change outer layer to yellow color and smell roasted. The second step 205-207°C (401–405°F) the coffee beans double in size before the first crack and then color change into light brown. Around 224-227°C (435–440°F) medium roast, the coffee beans emit the heat (Exothermic), what we see is second crack, melting or caramelization, oily surface, evaporation of coffee aroma and a lot of smoke with chaff too, and the color change to more darker shades with dry looking. Normally the roasted temperature level is between 240 – 275°C (460 – 530°F), and the period of roasting time is about 3 – 30 minutes. By the way after roasting, coffee flavor peak only 2 weeks shelf life and drop down while the fact, green coffee beans can be stored up to 2 years. What is up? Because of contact the air including the oxidation of oils and the coffee flavor evaporated, will decresed coffee beans flavor. Oh! this means loss of coffee flavor which coffee consumers expect to.

For further explaination, what chemical reaction occurs: strach in the coffee beans caramelize to sweeter sugar, maximize aromatic oils, minimize the bitterness and acidity change to flavor, other oils produce and soluble compounds. So what physical reaction changes: the structure of coffee beans change, lost water (dry looking), increase in size (more volume), decrease density (strength coffee), and change color. Obviously the roasted coffee beans vary in color: light, medium light, medium, medium dark, dark, or very dark. You can grade as roast level, the other word describing as degrees of roast. Normally they are called as typical name: drying phase, cinnamon roast, New england roast, American roast, City roast, Full city roast, Vienna roast, French roast, Italian roast, Spanish or Turkish roast. Different roasted coffee beans are determined by roasted temperature level and the period of roasting time. Yes, the different coffee flavor, aroma they are. I will talk about one by one someday. Well I know more, the deep roast level will be lower the caffeine levels in coffee. So decaffeine automatically. Which the caffeine level coffee you like. Go for it, Coffee addicts!

The Coffee roasting machine

Commercially, amount of roasted coffee beans at any degrees are sold by suppliers. Large manufacturers mainly consists of sorting, roasting, cooling, and packaging. Each coffee industrial roaster has standard roast profiles, unique roasted techniques and professional roasters to operate with capacity roasting machines under computer control. Normally, the most common roasting machines are of two basic types: drum roasters and hot-air roasters (or fluid bed roasters), although there are others including packed bed and centrifugal roasters. Well, especially various preservation techniques are used to extend shelf life such as pressure or vacuum packing in cans or foil bags, etc. So not only standard quality but also more longer shelf life roasted coffee. Sure it’s fulfil your easy lifstyle. That’s why you see the high price tags on them!

Roasting Coffee on Stovetop

Well, you can enjoy roasting by yourself at home. It’s called home roasting. You will be happy when you drink fresh, flavor coffee. You will smile when you pay less. Whereas you will be a little tired to do and of cousre lost your time. Asking yourself is it worth? Besides the common method: roasting small volumes of green beans with easy equipments: pan, stove and iron drums, you can choose various types of fresh coffee beans and other equipments, home roasting machines which are available and more comfortable. As you know coffee flavor is stale after roasting coffee about 2 weeks. I think this is a reasonable advantage why you need to do home roasting.

Image:
en.wikipedia.org: Coffee roasting
Flickr.com: Before……After By evvvvan
Flickr.com: Making Coffee By Grete Howard
Flickr.com: Roasting Coffee on Stovetop By INeedCoffee/CoffeeHero