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What is Filtration?
Filtration is a physical or mechanical purification process which is used to separate solids from liquids or liquids from gases. This is done through the use of a means by which only fluids can go through and larger solid particles are retained. Separation of fluids and solids may not be totally complete. The extent of filtration will depend on the mechanism and medium used for the process. Both pore size as well as thickness of the filter plays an important role in determining the quality of filtration.
This process is not to be confused with sieving which only involves a single medium for separation. There are various methods for filtration which involve the use of a filter media, filter aid along with gravity for flow. An alternative to this filtration method makes use of centrifugal force to allow particles to settle to the bottom.
Filtration is used in many kitchen preparations to help attain clarity and smooth textures in dishes. Soup stocks and sauces are common dishes to undergo the process of filtration. Common kitchen ingredients such as oil may also undergo this process to help refine them and eliminate any unwanted particles, tastes and the like.