HunterLab EasyMatch QC, User Manual

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EasyMatch QC User’s Manual Version 2.1
Measurement Values A-17
this chapter. Its range is approximately 1 to 11 units, with the more yellow, pale worts at the low end of
the scale and the redder color of dark worts, beers, and caramels at the upper end of the scale.
Applicable equations are given below.
( )
nm 430 10
T log - * 1.27 * 10 ASBC
=
where
T
430 nm
= measured transmittance value (%) at 430 nm
and
Turbidity = free (“0.0”) if
( )
nm 430 10
nm 700
10
T log - * 1.27 * 0.039
100
T
log - * 1.27
≤






, else turbid (“1.0”).
where
T
700 nm
= measured transmittance value (%) at 700 nm.
ASBC Difference is also available, and is defined as follows:
dASBC-10 mm = (ASBC-10 mm)
sample
- (ASBC-10 mm)
standard.
ASTM D1500-33 mm (ColorQuest II Sphere, ColorQuest XE, ColorQuest XT,
UltraScan PRO, UltraScan XE, and UltraScan VIS only)
The ASTM D1500 scale is calculated as described below.
D1500 = 0.25 + 0.8695 (DX + DY + DZ)
where






=
98.078
X
log - DX






=
100.00
Y
log - DY
if Z > 0.01,






=
118.24
Z
log - DZ
if Z
≤
0.01,






=
118.24
0.01
log - DZ
X is the X tristimulus value for the sample calculated for C/2° conditions
Y is the Y tristimulus value for the sample calculated for C/2° conditions