It was raining, and I had a coffee. and then I remember a lectures on coffee beans.
Have you tried brewing coffee with beans in a coffee maker? It does smell good isn't it?
well you're notice that the beans will stay cloud (or sediment, cloud is the term we used in food science) in the coffee maker. The coffee you drink is actually an extraction of the coffee beans. I bet you think that coffee bean dissolved in the coffee, isn't it? oh, and also, the aroma comes from heat-generated volatile compounds that is released when you brewing it.
That's for our friend in overseas. In Malaysia, I bet most of us will rare see a coffee maker let alone observe it. We used instant coffee here instead. like Nescafe, Kopiko, Kopi 434 and other instant coffee.Have you noticed that once we make the coffee, there will be sediment at the bottom of the cup? What make this happen?
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The instant coffee is a processed food, so it was made with mill ( a machine that make something into small size, powder size). There's many type and brand of mill machinary out there. But the quality of the powder it makes can be seen by the sediment formed your cup.
In a food processing, the smaller the size of the powder, the more soluble it is. We call it "size reduction" in the food industry and also in engineering. The instant coffee were made by grinding the coffee bean (as well as other things... which I should not tell you...yet) and reduce it into a powder form along with some sugar and cream.Usually, the smaller the size reduction, the more prone it will be damaged easily, especially during processing in the factory.
In the miller, there's a rotational metal slab that hammered these coarse coffee powder into a finer smooth powder. However, as the rotational become faster, there's bound for friction. This causes heat and may produce some size differences in the product. When in a sachet of instant coffee contains an uneven size powder, there's bound to be some sediment in the cup. Unless, you leave it for a while. This will dissolve the sediment, but make the coffee getting cold as well.
So, how about Nescafe? Nescafe is a bit different. Did you notice that the nescafe powder are easily soluble by water, even by some tiny droplets? At your kitchen, just put a small grain on top a table and just pour one tiny drop onto it. It will surely dissolve in a matter of second, regardless of temperature.
This because Nescafe is actually not made from grinded coarsed coffee bean. Instead, Nescafe is actually an extract of coffee beans that had been liquidized and solidify into powder form. No wonder that the nescafe is easily dissolve.
So, next time you drink something, look at the bottom of the cup.