Great for quick analysis in the field. Interchanger Kit holds one disc at a time. Sieve largest particles first, and then so forth.
Coffee Bean Grading has to do with a number of characteristics, one of the most important being size. Not oinly are larger beans generally more desirable, but bean size , density, and moisture are
three factors that must be taken in to consideration when establishing roast profiles
Bean Sizing Sieves are used to seperate the coffee beans by 64th of an inch increments, starting with 8/64ths, all the way up to 20/64ths of an inch. Different countries use different size classifications.
Although the millimeter equivelants on this popular chart, aren't exact,it fortunately doesn't have any real impact on the size analysis. The New York Grading Chart
has exact conversions, but both result in the
same distribution because the tolerences are too small to impact 64th inch seperations.
Endecotts makes stainless steel coffee bean sieves designed to fit on a standard sieve shaker. Their rigid construction is designed for accuracy and durability.
"Some say there is an art to great coffee. I don't care how artistic you are; there are too many factors in play. You need the technology."
Forbes Magazine, Bob Stiller Green Mountain Coffee
Grind analysis is a key component to producing a.good cup of coffee. Coffee companies spend tens of thousands of dollars on laser systems or less expensive sieving equipment to help analyze particle size and distribution, but why?
Grind distribution affects the extraction rate. Although there is no "correct distribution" this chart shows popular grind distributions for different grinds.
When performing a grind analysis, it is important to use USA Standard, or ASTM Mesh Designations, especially when dealing internationally. Some companies as well as countries have their own mesh designations,but ASTM (American Society for Testing Materials) introduced standardized designations in the early 1900's to help eliminate confusion.
#12 1.70mm
#16 1.18mm
#20 850 microns
#30 600 microns
#40 425 microns
#50 300 microns
Even size distribution assures consistent extraction rate. Target extractions of dissolved solids should be 18% to 22%
The smaller the coffee particle, the less contact time required to achieve optimal extraction. Water contact times vary between 1 to 4 minutes.Under extraction makes for a weak coffee. Over extraction releases undesireable chemical compunds that result in negative taste quailites like bitterness.
Regular grind size analysis provides important information on grinder settings and grinder maintenance requirements.
For start up sieving operations, certified coffee grind sieves are recommended, where the mesh has been inspected, and a copy of the signed inspection report is kept on file with the manufacturer, in the event of an audit.
This hand sieve shaker holds 4 sieves at a time. It should be noted that correct hand motion for effective sieving requires movement along the lines of 150 shakes per minute, and some mechanical sieve shakers can take 30 minutes to reach an endpoint. (Endpoint determination is where the amount retained on any one sieve changes less than 1% with one additional minute of continuous sieving.For audits .1% may be required.)
Although moisture plays an important role in coffee, we found no effective difference in grinder performance when comparing grinds with 2.8% to 4.8% moisture
