Turbidity

[beer_gorilla]

(X-post from Filtration)

hey all....with respect to turbidity (NTU scale), what are the standard ranges for beer? assumed this was something i could find info online about, but it is pretty sparse out there re: this.

best i can find is that brite beer should be 10-15NTU, but that is info i have gleaned from sources w/o them actually saying as much. that sound about right?

any thought on the ranges for filtered beer?

thanks in advance.

[TL Services]

All you need to know, and possibly more, can be found here:

http://resource.npl.co.uk/optical_radiation/ormclub/member/content/jun07/norman.pdf

As mentioned in the info, 90 degree scatter is also a valid parameter; typically this will pick out colloidal haze that narrow angle measurement won't. From experience, an increasing trend in 90 degree scatter can be the first sign of an impending chill-haze problem.

Hope that helps!

[beer_gorilla]

All you need to know, and possibly more, can be found here:

http://resource.npl.co.uk/optical_radiation/ormclub/member/content/jun07/norman.pdf

As mentioned in the info, 90 degree scatter is also a valid parameter; typically this will pick out colloidal haze that narrow angle measurement won't. From experience, an increasing trend in 90 degree scatter can be the first sign of an impending chill-haze problem.

Hope that helps!

thanks, but unfortunately this was one of the sources i had previously looked at that didn't make sense w/r to the numbers given.

based on the conversion table, 1 EBC = 0.25 NTU or 1 ASBC = 17.5 NTU. therefore, 1 EBC should equal 0.014 ASBC. this is consistent w/in the conversion table.

however, when you look at the descriptive scale, the relation doesn't hold (descriptive scale includes only EBC and ASBC, i calculated the respective NTU and the EBC to ASBC):

Brilliant:

• EBC = 0-0.5
• EBC to NTU = 0-0.125
• EBC to ASBC = 0-0.007
• ASBC = 0-34.5
• ASBC to NTU = 0-1.9

Almost Brilliant:

• EBC = 0.5-1.0
• EBC to NTU = 0.125-0.25
• EBC to ASBC = 0.007-0.014
• ASBC = 34.5-69
• ASBC to NTU = 1.9-3.9

Very Slightly Hazy:

• EBC = 1.0-2.0
• EBC to NTU = 0.25-0.5
• EBC to ASBC = 0.014-0.028
• ASBC = 69-138
• ASBC to NTU = 3.9-7.9

Slightly Hazy:

• EBC = 2.0-4.0
• EBC to NTU = 0.5-1.0
• EBC to ASBC = 0.028-0.056
• ASBC = 138-276
• ASBC to NTU = 7.9-15.7

Hazy:

• EBC = 4.0-8.0
• EBC to NTU = 1.0-2.0
• EBC to ASBC = 0.056-0.112
• ASBC = 276-552
• ASBC to NTU = 15.7-31.5

Very Hazy:

• EBC = >8.0
• EBC to NTU = >2.0
• EBC to ASBC = >0.112
• ASBC = >55.2
• ASBC to NTU = >31.5

the ASBC to NTU scale seems to hold true to other links I have seen (http://fscimage.fishersci.com/cmsass...10scansoft.pdf). but using the scale in the presentation, Brilliant beer is either 0-0.125 NTU or 0-1.9 NTU depend on if you calculated from EBC or ASBC. something has to be off in there as those are an order of magnitude different.

or am i crazy that this doesn't seem to make sense?

[TL Services]

I think you may have misinterpreted the table:

1 EBC = 4 NTU = 70 ASBC
1 ASBC = 0.014 EBC = 0.057 NTU

So for 'Brilliant' turbidity:

EBC = 0-0.5
EBC to NTU = 0-2
EBC to ASBC = 0-35
ASBC = 0-34.5
ASBC to NTU = 0-2

etc.

[beer_gorilla]

holy crap balls...i absolutely did. that is why the ASBC made sense and the EBC didn't. (can i blame beer for this? i'm going to go w/ the beer was in my eyes)

many thanks, my friend.