VST Inc.‘s Vince Fedele’s coffee quality hypothesis

In January 1999, late Apple CEO Steve Jobs was set to present to an audience on the advent of FireWire. The device was one of the first high speed serial interfaces that would both power and connect an external hard drive to a computer and was hot-pluggable. A few minutes before the presentation, he turned to VST Inc. CEO Vince Fedele and asked him when the first set of VST pocket-sized drives he was about to demonstrate would be ready to ship. Fedele had answered August, but when Jobs announced to the audience at large that it would be ready in June he glanced directly at Fedele, fully aware he had just moved up VST’s deadline by two months.  “That was how he challenged people,” recalls Fedele on the memorable moment which would see the company’s sales jump from US$20 million to over US$65 million a year. “Having Steve demonstrate a VST product was an extraordinary highlight in my technical career, and for everyone at VST who helped make that product a reality.” Always ready for a challenge, VST shipped the first portable FireWire drives in April, two months ahead of Job’s revised date, and a full 18 months before a single competitive product appeared. VST, VST Power Systems and VST Technologies have a long list of contributions to the computer world. From the first Smart Battery Chargers, USB products for iMac, the notebook versions of the Zip drive and the some of the first multiple format flash memory readers integrated with USB, the list is an impressive contribution to the way we interact with our computers today. After selling VST Technologies, Fedele moved on from Apple and lent his ingenuity to the FBI and state police crime lab, where he developed a high-resolution fingerprint imaging systems in 2003. These included 4000dpi FireWire imaging cameras and specialised machine vision software used to enroll and detect subsequent fingerprint images or partial images at very high speeds. The technology worked, and was intended by Fedele to mitigate the long security lines  Americans have endured following the 9/11 attacks. It worked by providing an ultra-high reliability identification of an individual to their passport ID. Because passports are generated using secured credentials, the chance of a false ID using these combined technologies is nil to none. As a trusted traveler, security screening could be streamlined, greatly reducing the queues we still endure today. “People could be identified as trusted travellers, virtually instantly,” Fedele says. In addition, for less than $1000, it could be used to authenticate a user to his/her government issues driver’s licence ID, virtually eliminating sales of alcohol to minors in bars, restaurants and retail sales. It was a negative experience – in that the technology was too far ahead of the US federal agencies ability to adopt and deploy it – that led Fedele away from pursuing it further. During an interview with a company who was working the secure ID issue with the US State Department and Passports, one of the interviewers mentioned to Fedele a rumour that George Howell, a pioneer in the American specialty coffee movement, was roasting coffee again. Fedele walked out of the interview, and away from a substantial compensation package, and drove to Howell’s roastery to confirm the news. With a long held passion for coffee, Fedele made an investment in, and started working with Howell, the dominant influence in Fedele’s perception of quality coffee. Fedele credits Howell with bringing strict quality control methods and processes to everything from cupping to processing, packaging and roasting. “Howell’s Coffee Connection cafés during the mid 1970s through the mid 1990s illuminated thousands to what coffee could be,” Fedele says. “His convictions to coffee quality and his passion for both learning and sharing what he has learned with the industry were leading motivations to help improve brewing quality and consistency.” The main benefactor of Fedele’s shift into coffee is now the industry at large. In a tale of discovery, Fedele has spent the last few years of his career bringing together a scientific problem solving approach to achieving the ultimate extraction, improving how espresso and coffee are brewed and modernising tools so that the industry can learn, understand and practice better brewing technique.
“It takes a year for coffee to grow from blossom to cup. Farmers at origin cultivate their coffee crop. Processors wash, dry, mill, package and transport all while striving to maintain green coffee quality. Roasters put so much work into what they do, and we can blow it in just the last five minutes,” he says. “VST’s goal was to deliver the most technological help possible, while making it easy to use in the field, without having to rely on formal labs to tell us how we did, with instant feedback as to the results.” The first of his steps towards this goal was the development of the coffee refractometer and the accompanying software. These products were followed with an espresso refractometer and a mobile version of the software for the iPhone called MoJoToGo. VST’s products have won Best of Show awards at Special Coffee Association of America (SCAA) in 2009 and again in 2010. The original brewing control chart was created under the direction of Ernest Lockhart at the Coffee Brewing Institute, around 1952. The chart was limited to coffee (not espresso) and a separate chart was needed for brewing in gallons, litres, cups, etc.  Fedele corrected errors in the original charts, and expanded the concept by adding a universal aspect to the math behind the chart, allowing a single chart to be used not only for any form of measurement (i.e volume or weight, litres, gallons, grams, ounces, fluid-ounces) and batch size, but also to be used for espresso for the first time.  Last year, at the World Coffee Events held in Maastrich, the three different forms of VST’s technology were everywhere to be seen. The coffee refractometers were being used for both the World Brewer’s Cup and Cupping Championships. The espresso refractometers and VST’s [iPhone] software were being used to judge the World Coffee Events (WCE) equipment testing for the espresso machine World Barista Championship (WBC) sponsorship competition, and another of VST’s imaging technologies was used to evaluate espresso filter baskets as part of that evaluation. The Special Coffee Association of Europe (SCAE) was using the coffee refractometer and software for their research on preferred extraction yield taste surveys. Indeed, VST’s products have been adopted as official measurement tools at the SCAE, SCAA, National Coffee Association (NCA) and European Coffee Brewing Centre (ECBC), and are used at many espresso and coffee brewing equipment manufacturers during the design of their equipment. “I like to compare [the chart] to a map. When you go to a foreign place you’ve never visited before, you often use a GPS, right?” he says. “What’s the first thing you do? You press ‘here’. Why? So that you know where you are. Why? So that you can navigate to where you want to be. The universal brewing control chart works exactly the same way. The coffee refractometer and VST software allow you to do that, and they’re small enough to put in your pocket, bringing to the field what used to require an entire lab.” The original chart from the 1950s shows a brew formula of gallons of water per pound of coffee on the horizontal axis, and extracted solids in percentages in the vertical axis. Fedele points to the gallons per pound measurements as a sign of the times, when coffee was prepared in large urns. The chart shows how the various extraction yields play against the formulas, plotting the ideal combination for the best tasting coffee in a very small region on a very large chart. The chart emphasises just how much precision is required to brew coffee correctly, and repeat it brew after brew.   As the brewing control chart indicates, the key to a better tasting coffee is the extraction yield, which Fedele clarifies as different than the brew strength. Concentration (strength), he explains, is a personal preference. No one enjoys a sour or bitter coffee (i.e. under or over-extracted), but everyone loves a sweet extraction yield. People are less likely to dislike a coffee that is slightly stronger or weaker (i.e. more or less concentration) as long as the coffee was extracted near the centre (sweetest) part of the extraction yield range. The human palate is very sensitive to extraction yield and can detect a change of as little as +/- 1 or 2 per cent, so this is where brewing precision pays off most. Extraction yield is the measure of coffee that is dissolved into a solution. If you were to take a spent puck out of the basket, dry it and weigh it, the difference from the original weight of the coffee compared to the original weight expressed as a percentage is the extraction percentage or yield. For espresso, Fedele says most people agree that most coffees taste best when extracted to about19 – 21 per cent to get the best balance of aroma, flavour, body, colour and clarity out of the coffee. In expanding the application of the original chart, Fedele found a 4 per cent error due to the original formulae not taking into account the density of water as a function of temperature. At the time the charts were done, urns were used for most commercially prepared coffee, and were filled with tap temperature water, whereas today, brewers store water at 94 degrees Celsius. One litre of water at 94 degrees Celsius contains (i.e. weighs) about 4 per cent less than one litre at 15 degrees Celsius. Therefore, the amount of coffee used must be adjusted by 4 per cent, otherwise a different brew formula applies. When brewing commercial batches, this error adds up. For a 6-litre batch, it accumulates to 217grams of water or 13 grams of coffee. The updated chart, however, wouldn’t be of much use to the coffee industry without a simple and reliable way to physically measure the extraction yield, and use it in the field. Prior to Fedele’s development of the refractometer and software, the only way someone could accurately measure the yield was through highly advanced, and expensive, lab equipment. Borrowing from his experience in making information tools portable in the Apple realm, and his experience in optical imaging and refractive optics, Fedele took his first steps towards applying technology to his passion for coffee by developing the refractometer and software for coffee beverages in 2008. The espresso refractometer followed in 2009. Both allow instant total dissolvable solids (TDS) measurements and extraction yield results with a simple, on the spot procedure. The coffee refractometer can be used with VST’s software to plot these readings on the universal brewing chart, and there is now even an iPhone app that calculates brew formula, proper water and coffee portions and computes extraction yield. Measurements can be saved and shared instantly anywhere in the world. “What used to cost US$50,000 in equipment performed in a lab, can now be done in the field with nothing but this portable digital coffee refractometer and an iPhone,” he says. As is often the case, new technology has the potential to reveal as many problems as it solves. While Fedele had created a measuring tool to find out where coffee was on the map, it didn’t fully solve how to get to where a barista wanted to go. Under carefully controlled conditions, Fedele attempted to repeat similar espresso extractions using different groups on the same machine, but found he was getting significantly different results. The problem was first highlighted for him in his work with Howell. After installing a new account with a brand new LaMarzocco machine, Fedele recounts, the client called and complained about the coffee tasting sour. But the same coffee tasted fine at the shop. In troubleshooting they changed water filters, burrs, the grinder – they even tried using formulated bottled water – but nothing resolved the problem. In reviewing all the variables, Fedele realised that he had never thought to check the filters. As it turned out, they were using different filters than what was supplied with the machine. Fedele borrowed the filter, and brought it to his lab at VST where he had a high resolution imaging system similar to the one he had developed for the FBI. The resulting images came as both a shock and a revelation. The preliminary software analysis showed that filters were anything but a clean pattern of uniform holes, but rather a minefield of various sized punches, blocked or partially blocked holes, ranging five to one in size. Fedele explains that extraction yield in espresso is controlled primarily by flow rate, which controls the effective time for extraction. Since most espresso machines have similar pressure, aperture restrictions and temperatures at the group, flow rate is controlled primarily by coffee grind particle size, coffee amount, and total open square area – that is, the cumulative total square area of the filter openings. Filters examined on the VST imaging system had total open area that varied by more than 3:1 in filters from the same manufacturer, with the same part number – in fact from the same lot.  A filter with 27 square millimetres of total open area will flow much more slowly than the same filter with 97, all other variables being equal. “When filters with a severe restriction find their way to a machine, a substantial reduction in-flow occurs,” he says. “The barista makes the only adjustment possible, not knowing or being able to see visibly that the filter is defective, they grind more coarse. This reduces the available area of the ground bean from which to extract, and although the flow is returned to normal, the coffee tastes sour, and measures significantly under-extracted.” All this was not necessarily news in the industry, Fedele says. There was a long-held belief that the quality of filter baskets had to be improved. The problem was that, without the imaging technology, and a way to measure how filters affected extraction yield, there was no way to measure the consistency of fabrication or how to tune the filter design to extract in the centre of the yield curve. From here, Fedele adapted his imaging system to measure and grade dozens of aspects of hole sizes, shapes and fabrication quality that affected filter performance. VST then developed several new manufacturing processes that addressed precision and hole size distributions, and finally developed a method of tuning a filter for extraction yield performance. The imaging system needed to be fast, with the ability to measure hundreds of filters a minute, so that all filters could routinely be measured to ensure specifications were being met and performance was identical on all filters of a given design. VST’s filter imagining system also grades the baskets to specific manufacturing and performance standards. Each basket is marked with a 2D data matrix code to track it through the manufacturing and testing process, and to ensure authenticity.  Factory measurements are stored, and reports generated for each filter, quality reports and image data are also captured and stored and are monitored during production to ensure tooling remains in specification, and serve as an indicator as to when to replace and refresh certain components of the tools. The baskets have proven a popular uptake with specialty coffee companies the world-over. Many of the world’s top baristas and specialty roasters have adopted them for their own café operations and resell them to their coffee clients. The list of users include WBC champions, as well as some of the most recognized quality cafes and roasters in the world. La Marzocco of Florence was the first to engage VST to design their latest Strada filters and purchased the first VST Filter Imaging system, giving them direct control over the quality of their filters for the first time. Most recently, the company entered into a collaboration with espresso machine manufacturers Nuova Simonelli, who last year renewed their position as official machine sponsor of the WBC. Nuova Simonelli announced at HOST Milan last October that VST will be manufacturing a custom 20-gram precision competition basket specifically commissioned by Nuova Simonelli for use in WBC events on their new Aurelia II T3 machines. And so it would seem that after putting his technology in the hands of some of the world’s greatest computer icons, and now some of the world’s greatest coffee professionals, Fedele’s technology is once again set to take centre stage. 

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