STiR coffee and tea magazine

32 STiR coffee and tea / Issue 2, 2019 (April / May) C MPE: Perfecting the Grind By Peter Keen Daniel Ephraim with Modern Processing Equipment's (MPE) 600.IS the first "in place" roller grinder for capsule and pod manu- facturing. This all-in-one grinder can be installed in tandem with capsule filling machines. It produces an optimal grind for "K" cup, espresso, and virtually any grind required for single-serve capsule applications. offee is a commodity crop, but today's consumer demands an ever-improving and more varied premium product. And gets it. There's now almost an implicit 28th amendment guaranteeing the constitutional right to good coffee. Dan Ephraim, the c.e.o. of Modern Process Equipment (MPE), comments that "60% of all coffee now sold in the United States is of a premium variety. Thirty-five years ago, this number was 5%." Coffee starts out as a green bean and ends up as particles. The steps in between are loosely termed "processing", but they must be value multipliers. If the bean is treated as a commodity, the result is predictable, and no amount of marketing will prevent coffee lovers exercising their right and going elsewhere. It's not enough in such a competitive market where buyers have well-educated taste buds just to "add" value. The key is to multiply it. The core of multiplication is in perfecting the grinding and integrating it into the full operations stream. That stretches from receipt of the green bean and transporting it to the machines so that its aromatics and volatiles are preserved through to packaging it as filter, pour over, capsule, po, etc., and differentiating it as macchiato, Turkish, light roast, cold brew, Cubano, and other yet to appear exotics, blends, and fusions. Ephraim describes "perfecting the grind" as both art and science. The art is in the flavor creation and the science in machines that operate closer to the molecular level than the bean. The cellular walls of ground coffee particles are around 30 microns in diameter. Extracting, without over-extracting, the soluble solids from the colloidal structures of the cells is "the secret sauce" of coffee brewing. Grinding creates the ingredients for the sauce: microscopic particles. The particles must be perfectly bal- anced to suit the brewing method. That includes being standardized in their output from the grinding equipment, even though the exact composition of the input green coffee will vary. Brewing is highly sensitive to particle surface area, which means that optimal quality depends on precision and consistency in tailoring the grind size to the brewing method. This is very much a matter of small is beautiful. The value multipliers are substantial. There's 600% difference be- tween a coarse filter brew grind where the average particle size is 800 microns and the retail value 2-3 cents a gram, to a 550-micron capsule grind generating 4-5 cents a gram, up to a 300-micron espresso grind at 12 cents. This trans- lates to $11/lb. for coarse to $20/lb. for drip to $54/lb. for single serve espresso. The standard example for getting a sense of what micrometer (the full term: mil- lionths of a meter) measures translate to is that a human hair averages 75 microns. So, in this example, reducing particle size from 10 hair widths to four multiplies the coffee value by factor of 6. The technology needed here is obvi- ously complex in the basic science and in the engineering. There are multiple fac- tors to balance and trade off, including

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