Difracción de rayos X (XRD)
Una técnica no destructiva para estudiar todo tipo de material
| 00:00:00 | Welcome |
| 00:00:46 | The science of coffee - particle size distribution |
| 00:01:37 | Abstract |
| 00:02:19 | Obligatory Opening Quotation |
| 00:03:09 | Coffee consumption (2008 data)http://en.wikipedia.org/wiki/List_of_countries_by_coffee_consumption_per_capita |
| 00:04:02 | W H Ukers “All About Coffee” The Tea and Coffee Trade Journal Company New York (1922) page xxix |
| 00:05:01 | The roasting process – 9 to 15 minutes typically |
| 00:06:16 | Adapted from: www.mahlkoenig.com/events/whitepaper/4269 |
| 00:07:56 | Fluidized bed, sir? US Patent 3964175 (June 22nd 1976) |
| 00:08:42 | Specialist Coffee Association of America (SCAA)Brew chart |
| 00:10:16 | Why control the grind? |
| 00:11:28 | http://coffeetea.about.com/od/grinding/a/grindguide.htm |
| 00:12:28 | How to grindFrom: http://mic.com/articles/103114/how-to-brew-and-drink-the-perfect-cup-of-coffee-according-to-science |
| 00:13:34 | The nanny-state – your tax dollars at work….. |
| 00:14:44 | Same year as ‘The Art of Coffee-Making’ |
| 00:15:33 | Hills Bros. (contd) |
| 00:16:21 | Coffee Grinds, Simplified Practice R231-48, United States Dept. of Commerce (1948) |
| 00:18:01 | And there’s more…. |
| 00:18:40 | Acceptors |
| 00:19:16 | We note that…. |
| 00:20:22 | Lockhart (MIT Professor) recommendation |
| 00:21:12 | Lockhart continued - Tyler #28 (595 μm) |
| 00:21:49 | Lockhart recommended graphical plotting |
| 00:22:55 | Daniel Ephraim – pronounced “Ē-from”D Ephraim “Coffee grinding and its impact on brewed coffee quality” Tea and Coffee Trade Journal vol. 176(11), (November 2003)http://www.mpechicago.com/coffee/images/uploads/pdfs/coffee_grinding_nov03.pdf |
| 00:24:23 | Ephraim |
| 00:25:13 | Ephraim |
| 00:26:34 | Ephraim |
| 00:27:09 | Ephraim |
| 00:27:41 | The grinding process |
| 00:28:47 | Gump 888E coffee grinderhttps://www.youtube.com/watch?v=QquddUt5zXY |
| 00:29:00 | Gump 888E Video |
| 00:29:00 | US Patent 3190572 Granted June 22, 1965 Jyunichi Goto “Kasai” |
| 00:29:43 | Why laser diffraction? |
| 00:30:38 | Measurement principle |
| 00:33:02 | Measurement principle (Rose) |
| 00:34:18 | Halo around moon http://apod.nasa.gov/apod/ap030421.html |
| 00:34:49 | Size of droplets |
| 00:35:35 | Mastersizer 3000: optics layout |
| 00:36:17 | Different coffees on MS3000 |
| 00:36:40 | Controlling the grind |
| 00:37:02 | Instant coffeeKato - 1901 |
| 00:37:29 | Coffee powderhttp://en.wikipedia.org/wiki/Instant_coffee |
| 00:38:13 | Espresso (not expresso…) |
| 00:39:03 | (real) Density of coffee; contrast with apparent or bulk density |
| 00:39:29 | P. C. Corrêa et al |
| 00:40:03 | Minimum mass |
| 00:41:15 | Minimum mass where x99 is at given point1% standard error (99% confidence limits) |
| 00:42:12 | Lower the bar: x90 @ 5% S.E. (250 times less sample…) |
| 00:42:49 | Practical considerations for dry analysis |
| 00:44:52 | Untitled |
| 00:45:17 | Untitled |
| 00:45:38 | The new dry powder feeder accessory – the FSF |
| 00:46:08 | Aero S Funnel Sample Feeder for coffee quality control measurements |
| 00:46:52 | Measuring coffee – the Funnel Sample Feeder (FSF) |
| 00:47:25 | Measurement reproducibility for a very coarse and a very fine coffee grind |
| 00:47:45 | Individual measurements |
| 00:48:42 | Funnel Sample Feeder |
| 00:48:42 | On-line too - De’Longhi |
| 00:48:58 | References |
| 00:49:47 | Effect of caffeine on spider’s webs |
| 00:50:15 | Thank you! |
Many coffee manufacturers control the grinding of coffee beans using the laser diffraction technique. We will outline the history of coffee manufacture and the influence particle size has on dissolution and thus taste of the brewed material. We will be revealing details of a new dry powder accessory for the Mastersizer 3000 that allows significantly more sample volume to be measured and is thus advantageous for ground coffee measurement where the top end size may exceed 3 mm or so. We will also briefly explain the top end size in the context of sampling reference specifically to coffee analysis.