Just a note on filtered water. While I completely agree that the quality of the water makes a big difference, filtered water does not really protect the machine from lime scale. If we are talking about "filtered", as in a Brita filter, or Culligan filter...they both will remove elements that, when removed, improve the taste of the coffee. However, lime scale which, among other nasty things, seriously effects the functioning of the boiler, and therefore effects reaching proper temperature, is caused by calcium carbonate (not removed by filtering)...what is often called "hard water". If the machine does not have a built in (and replaceable) water softener cartridge, frequent de-scaling of the machine is necessary. Even with a water softener cartridge, de-scaling is still necessary, but not as frequently.
So, the use of filtered water is, I fully agree, necessary for the taste of the coffee, water softener and de-scaling is essential for the proper functioning of the machine...
Once again, I acknowledge my lack of specific knowledge of Keurig systems. My comments are general in regard to espresso and drip machines...and perhaps Keurig, but others are better able to comment specifically on those coffee machines.
I used to use vinegar to descale my coffee maker, but have not done so recently. It makes the house smell real good.
The new Nespresso line (VirtuoLine) claims to produce a significant amount of crema with each cup. Viz:
Image
The problem is, it isn't crema. Once it pulls the "shot," the VL spins the coffee at a high speed and uses a little metal fork to whip the coffee, which produces a prodigious amount of foam, which you can see in the picture above, but it is not crema. It is just lots of tiny little bubbles that lack the fat/oil emulsification that is crema's most important ingredient.
Beyond that, I don't really care if they call it crema or not, but (and I will try to say this without violating Shrink's Law) to me everything about that foam is off-putting; the flavor, the consistency, everything just generally unpleasant. I'm sure it is a good marketing technique vs. the K cup line, and you have to believe they tested the stuff in consumer focus groups and the like, but even given the general lack of appreciation for fresh and properly made coffee in the US, I will be very surprised if the new line takes off. But, of course, I am usually wrong when it comes to calling popular tastes.
I don't like foam on beer or coffee.