0% IBU IPA

Theoretically zero IBUs exists but realistically there will always be some level of alpha acid in the beer and therefore some bitterness levels.

 

Yeah, that is called wort, and it is sticky sweet stuff!

 

Craft beer and brewing, aug-sep 2017, Stan Hieronymous, understanding bitterness page 80...
"The standard IBU test, using uv spectrophotometric analysis, does not work for heavily dryhopped beers because iso alpha acids, alpha acids, and humulones absorb light differently at the wavelength used for testing. Because each hops acid has a different level of bitterness intensity, it is not possible to directly correlate IBU to bitterness. ".
So... yeah. Science.

 

why not just drink a mimosa? You can use any type of fruit juice you want - get that mango, papaya taste you are looking for in a NEIPA and you don't have to wait in line. Unless its a line for brunch where mimosas are usually served.

 

HPLC can measure the differences in those compounds. Big expensive science.

 

The next paragraph mentions that. It's a great read for anyone wishing to see some newer science regarding bitterness.

 

I don't have a subscription - have been considering. Couldn't find the article online yet. Stan did talk at HomebrewCon, mostly about aromas. He did the talk with a Prof from Southern Illinois that is doing research that Stan can review. The lab is fully equipped. I will have to go back and listen to his talk once posted.

An analytical chemist friend explained HPLCS to me, so it make sense that they separately measure the compounds.

The link I posted above to Scott Janish's blog compares his spectrophotometer and HPLC results.

 

Jeff, do you have any idea when the 2017 stuff will be posted?

Is there an agreed upon standard on how IBUs are determined via HPLC?

Cheers!

 

For a bit more science, it's also presently not possible to directly correlate IBUs to bitterness because bitterness is what is perceived by humans and IBUs are what are measured by physical testing of chemical presences that have only a loose and complex relationship to perception of bitterness.

In the absence of carefully controlled sensory testing under a variety of circumstances to establish a relationship between the physical world and the sensory reactions to the characteristics of that world anything else is simple guesswork and estimation no matter how accurately and precisely IBUs can be measured. For example, a detectable difference in chemicals doesn't guarantee that the difference is detectable by humans.

https://en.wikipedia.org/wiki/Just-noticeable_difference

@hopfenunmaltz

 

The 2017 stuff should be soon, or so they say. I haven't looked yet.

This says there are some methods, but I am not a member.

http://methods.asbcnet.org/toc.aspx

 

I took note of:

“Beer 23. Beer Bitterness

VIEW SUMMARY | VIEW METHOD

A. Bitterness Units (International Method) [Release date 1968, revised 1975]

B. ISO-α-Acids by Solvent Extraction [Release date 1968, revised 2011]

C. ISO-α-Acids by Solid-Phase Extraction and HPLC [Release date 1993]

D. Bitterness Units by Automated Flow Analysis [Release date 1995]

E. ISO-α-Acids in Beer by HPLC [Release date 2011]

F. ISO-α-Acids (IAA) [Release date 2011]”

From the above it appears that Bitterness Units (e.g., IBUs) is determined by two methods:

· Beer 23 a which is via a spectrophermetric method

· Beer 23 d which is by Automated Flow Analysis (are you familiar with this method?)

It appears that HPLC is used to measure ISO- α-Acids which relates to bitterness but not exactly IBUs per se.

Cheers!

 

One Professor I know said there are 2 maybe 3 HPLCs used in the Michigan brewing industry. That has to do with the cost and trained personnel to operate it.

From what a friend explained, it probably could measure ISO-AA. I will see that guy in a month, and will have a discussion over a beer.

 

I think the problem at hand, at least from my perspective, is by advertising a zero ibu ipa people come to expect a no bitterness ipa. While it may have zero ibu from boil additions, there are still bittering agents. I also find that these 100% late addition beers are laden with chlorophyl flavors that come across astringent, adding an unwanted flavor to my beer. Once I age it a bit it gives me a small window to enjoy my beer. I have a half case of juicy bits clone that is brat beer now as a result of the short shelf life. In the end I think it's a marketing ploy, and a misleading one at that, to label a beer as zero ibu.

 

Jeff, I appreciate you having this discussion with your friend.

HPLC certainly does obtain enumerated results but how does somebody 'translate' those various values into an integrated IBU value and is that 'calculation' an agreed upon (i.e., ASBC) standard?

Cheers!

 

I think more research has to happen for that to be a reality.

 

That is indeed possible.

I will be very interested in hearing what you learn via your conversation with your friend.

Cheers!

 

If it's labeled as an IPA, it should have some noticeable hop bitterness. Otherwise, it's not an IPA....

 

If you read the Scott Janice blog I linked above, he had IBUs measured with both instruments. The researchers would probably need to look at beers conventionally brewed first to see if they can correlate. A beer with boil hops only, like they used for the original IBU measurements.

 

Jason,

The topic of 0 IBU IPAs is complicated on a number of levels.

I will be utilizing the Scott Janish blogs in my below discussion.

Are IPAs that are brewed using no boil additions truly 0 IBUs?

The answer is no as regards to the Scott Janish beer. He sent his beer to S.S. Steiner and he obtained the following results for his beer:

· IBU = 76.9

· 2.7 ppm iso-alpha-acids

It is my understanding that the IBU value obtained of 76.9 IBUs was via an ASBC Beer 23-a assay. The value of 2.7 ppm iso-alpha-acids was via HPLC measurement. As can be easily discerned neither of these values is 0.

Do 0 IBU IPAs taste bitter

As was discussed above there is indeed some amount of iso-alpha-acids in the beer so there will indeed be some bitterness in the beer from that aspect. As you are aware there is also the concept of perceived bitterness. Perceived bitterness is indeed a valid concept but needless to say there is no agreed upon standard akin to the ASBC Beer 23-a assay to measure perceived bitterness.

Scott Janish discusses a notion of:

“calculated bitterness (HPLC) = ppm iso-α-acids + (0.66 × ppm humulinone) + (0.10 x ppm alpha-acids)”

It can be easily discerned from the above equation that Scott is suggesting that there are three elements that provide bitterness to beer:

· iso-α-acids

· humulinone (with a percentage ‘fudge factor)

· alpha-acids (with a percentage ‘fudge factor’)

Using the results that Scott obtained via the S.S. Steiner;

· 24.3 ppm humulionones

· 2.7 ppm iso-alpha-acids

· 71.5 ppm alpha-acids

And then doing some math:

Calculated Bitterness (HPLC) = 2.7 + (0.66 x 24.3) + (0.1 x 71.5)

Calculated Bitterness (HPLC) = 25.85

So, it appears that Scott is suggested a value of 25.85 for the level of bitterness (perceived bitterness?) in the beer he brewed using no boiling hops.

Hopefully Jeff will learn some more ‘science’ from his future discussion with his friend and we will collectively learn more.

Cheers!

P.S. On August 23, 2017 a presentation entitled “Dry Hopping & its Effect on Beer Bitterness, the IBU Test, Beer Foam, and pH” will be conducted which relates to this topic.

A teaser for that presentation is: “The IBU test results of dry hopped beers does not correlate with sensory bitterness”. I would suggest that this result is borne out via Scott’s test result that his beer had 76.9 IBUs.

http://www.asbcnet.org/publications/webinars/Pages/2017-08-23.aspx

 

@JackHorzempa so it's really a simple answer in that 0 ibu is impossible and therefore this trend is lying to consumers.