Paper coffee filters were invented in Germany by Melitta Bentz in 1908  and are commonly used for drip brew all over the world. In 1954 the Wigomat , invented by Gottlob Widmann , was patented in Germany being the first electrical drip brewer.  Drip brew coffee makers replaced the coffee percolator in the 1970s due to the percolators' tendency to over-extract coffee, thereby making it bitter.  One benefit of paper filters is that the used grounds and the filter may be disposed of together, without a need to clean the filter. Permanent filters are now also common, made of thin perforated metal sheets or fine plastic mesh that restrain the grounds but allow the coffee to pass, thus eliminating the need to have to purchase separate filters which sometimes cannot be found in some parts of the world. These add to the maintenance of the machine, but reduce overall cost and produce less waste.
Once our analysis is complete, we then rank each company's performance. We rate the companies using a pre-designed formula that looks at how well they adhere to the qualities that students, in their reviews, say are most critical to them. After rating the writing companies against these qualities, we rank them according to their performance on a numerical score. The ranking process generates a list of the best writing services featuring at the top. With this information, students can be able to identify the most reputable writing services that they can trust to produce the quality of outputs they need. We publish these reports on this website so that students can find and use them to inform their choice of writing services.
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