Have you ever gone to the store looked at the coffee filter aisle and been a little confused as to what the heck is the difference?! Flat bottom filters, cone filters, paper filters, mesh filters, whitened filters, natural filters... We know it can be a little daunting. That is why we asked Dr. Brew to explain the different filters on the market and how they can affect the coffee in your cup.
As Dr. Brew explains in this video a variety of filters are used to accommodate a wide range of individual preferences.
Filters can vary in shape. They can be cone shaped or flat bottomed. The shape of your brew basket will indicate what shape of filter you need to use. However, you may be asking what's the difference when it comes to brewing with the different shaped filters? Flat bottom filters allow for a level bed of coffee. A cone filter on the other hand has a graded bed depth, with more coffee on top and tapers to less coffee on the bottom. A level bed of one to two inches of dry grounds for coffee brewing is recommended, as coffee actual expands during the brewing process. A level bed allows the water to flow through the grounds evenly which can deliver a more uniform extraction.
Filters can also be composed of different types of material. They can be cloth, metal or paper. Cloth filters are typically made of cloth such as muslin. This type of filter is not used in BUNN brewers and is more common in manual pour over methods. With this method the cloth must be washed after each use. Due to maintenance issues, cloth filters have faded out of popularity. Like the cloth filters metal filters require maintenance after each use. Metal filters let a certain amount of coffee sediments into the beverage which will make the coffee have a mouth feel similar to French press.
Paper filters can be natural/ unwhitened filter or whitened filters. As Dr. Brew explains there is an ongoing debate about filters that have been whitened versus those which have a "natural" coloration. He invites people to do a little test at home to decide which option is right for you. Dr. Brew does a test in his beverage lab where he puts a filter of each type into a clear glass of hot water. Within a minute or so, the color of water in the glass with the unwhitened filter has taken on a slightly yellow tinge and you can smell the paper pulp. He says if you can smell something, you can taste it. That means that the taste and color of the beverage brewed with this filter will be affected.
We recommend if you use a BUNN brewer to use BUNN filters. Why? BUNN filters are flat bottom filters that are specially designed to work with BUNN home brewers. They are 1/4-inch taller than other filters to allow for the quick flow of water into the brew funnel and the needed mixing action for complete, even extraction. The taller sides accommodate the fast brewing of a BUNN brewer overflow and grounds in your coffee.
The filter you chose to use depends on what you want in the final beverage, as well as your individual preference. As Dr. Brew says "experiment to find out what filter is right for you." Watch the video where Dr. Brew explains the different filters and the affect on brewing. Happy brewing!
Technical Tips The Evolution of and Reasons for Filters. Randy Pope. Tea & Coffee Asia. http://www.teacoffeeasia.com/section-blog/44-features-q3-09/135-technical-tips-the-evolution-of-and-reasons-for-filters.html