In short WDT stands for 'Weiss Distribution Technique'. It is a distribution method for espresso making. Using a fine acupuncture type needles or similar, and stiring the coffee while it sits in the portafilter. This action breaks up any clumps, and evens out the density of coffee. The result is reduced channelling, and more even extractions.
The WDT method was named for John Weiss, who developed the technique back in 2005. He developed it to compensate for grinders, especially domestic ones, that's coffee came out with too many clumps.
All grinders we sell at Bella Barista do include features designed to break up large clumps. However, in recent years, there has been a rise in people spraying their beans with a small amount of water being grinding them through to reduce static. Therefore, even with cleverly designed clump crushers, WDT'ing has become an essential part of many home baristas work flow.
To aid in our customers workflow, we have done extensive testing to find the perfect needle distributor. Our new Bella Barista Rotating Needle distributor tool has 9 0.06mm needles stainless steel needles, and sits on a brush stand which keeps it clean. To use it you simply rest the tool on top of your portafilter handle and spin the top part to rotate the needles, breaking the clumps of coffee allowing for a fluffy bed of coffee ready for tamping.
So we'll leave the question out there for all our home barista's that come to our website seeking the perfect espresso? Should you WDT?