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Coffee Degas Equation

  1. Mar 11, 2012 #1
    Hi guys,
    I've come across this article (http://www.probat.com/fileadmin/user_upload/Know-How/Entgasungsverhalten/2008_Vortrag_degassing_e.pdf [Broken]) about measuring the degas volume of fresh roasted ground coffee. They basically put ground coffee inside a gas tight bin and monitor the pressure and temperature to determine the degas volume. But, I can't figure out how they came up with this equation to determine the degas volume. Does anyone understand this equation? The original equation can be found in the article.

    [tex]V_d[\frac{Nml}{500g}] = [\frac{(V_b-V_f)(P_u+P_i)}{P_n}\frac{T_n}{T_n+T_i}-(V_b-V_f)\frac{P_s}{P_n}\frac{T_n}{T_n+T_s}] \frac {500} {G_f}[/tex]

    Vd=degassing volume
    Vb=bin volume
    Vf=filling volume
    Pu=surrounding pressure
    Pi=pressure inside bin
    Pn=norm pressure
    Ps=inside pressure when measuring
    Tn=norm temperature
    Ti=temperature inside bin
    Ts=temperature when measuring
    Gf=filling weight
    Last edited by a moderator: May 5, 2017
  2. jcsd
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