There are 2 major weaknesses in the Mr. Coffee auto drip coffee maker brewing method. The first is, it makes coffee too fast. The hot water does not have time to efficiently extract the coffee flavors from the grounds. This is model BVMC-PSTX91 but this applies to many similar models.
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Step 1: Slow Down the Water in the Filter.
Too extend the amount of time the hot water is in contact with the coffee grounds, I use a metal mesh basket in combination with a paper filter. The metal mesh basket forces the water to exit out the sides maximizing contact with the grounds. The paper filter keeps fine grounds out of my coffee cup and slightly slows the brewing process.
Step 2: Coffee Bloom Mr. Coffee Style.
One important step performed during manual coffee preparation is busting the bloom. When hot water is poured onto fresh ground coffee, carbon dioxide is released and the outer perimeter of the grounds is lifted up. These lifted grounds need to be wetted either by pouring water over them or by stirring. Otherwise the coffee extraction will not be very efficient. The photo in this step shows a bloom created after 2 cups of water were dripped onto the filters. The Mr. Coffee drips directly in the middle of the basket creating a very nice bloom but if left undisturbed this results in a rather weak and tasteless cup of coffee.
Step 3: Busting the Bloom.
What I do is after the first 2 cups of water are dripped into the filter basket, I remove the carafe from the unit consequently stopping the brewing process. I wait 5 seconds for the water to stop flowing. At this time I remove the filter basket holder from the Mr. Coffee unit with my righthand and give the grounds a quick stir with a spoon using my lefthand. Do not put the water filled basket on the countertop. The flow control button on the bottom of the basket will release hot coffee all over your counter. Stirring the bloom wets all of the grounds as shown in the photo.
Step 4: The Result Is Better Coffee.
This is what the filters look like near the end of the brewing process. The grounds are uniformly wet and evenly distributed throughout the filters. If you use this brewer with just a paper filter and do not bust the bloom, there is a large crater in the middle of the basket with unextracted grounds pushed up the sides. And the resulting coffee is rather weak and tasteless.
I noticed that newer Mr. Coffee models are marketed as having optimum bloom performance. I have not tried these new units so I do know what is involved but at least they realize the importance of proper bloom handling.