Brewing and Malting Science - Case Study

[evily]

So, Oct 24 - Nov 3, I will be attending the MBAA Brewing and Malting Science class. It's two weeks of very intensive study of the biology, chemistry, and physics of beer-making in every step of the process. As an engineer and science nerd, I'm really looking forward to it! We received our class roster yesterday and I'm delighted to see I'll be joined by folks from Deschutes, New Belgium, Bell's, Ommegang, Founders, and tons more (even some folks from Japan!).

One of the requirements of the class is that we have to work in teams of 8 people on a case study, and present our thought processes, recommendations, reasoning, etc to the entire class at the end of the 2 weeks. We received our case study assignments yesterday. Obviously, the intent is that we will learn a lot of things in the class that will better equip us to address the case study from a technical perspective. However, the intent is also that we network with other brewers and build off each others' experiences and knowledge. So I thought to myself, who better to network with than the Borg??? There is a wealth of knowledge on this form, so I want to share my team's case study assignment with you all, and get your thoughts.

Here's the assignment:

General Instructions:
You are a member of a task force at your brewery and have been given a high priority assignment. Your team assignment is described below. Your team will present your solution to the problem on the last day of class using PowerPoint. Each team will have 30 mins to do this, 20 mins for presentation and 10 mins for questions from both the expert panel and other members of your class. Your team can work on this assignment after class at your discretion.
Please keep in mind there are no correct answers only pathways to identify the issues. Additionally, the best solutions are those that cut into the investigation using a process that is deep into the process rather than overviewing all that you have been presented during the class. Use your judgement and set the stage for your investigation and solution. The winner of the six case studies will be selected by your class mates and expert panel. The winning presentation will be given an opportunity to publish their presentation in the Technical Quarterly.

And here is my team's particular problem to solve:

Malt Extract Loss Case Study
You are the brewing manager responsible for the operation of a brewhouse of a 200,000 bbl brewing operation. Recently your brewery shifted malt suppliers. The malt you were receiving and your new malt supply had similar malt analysis and was also similar in the barley varieties. When you started using the new malt you noted a significant drop in recovered extract in the brewhouse. Explain what approach you would take to identify, verify and correct this loss of extract.

Alright, GO!

[mashani]

Perhaps dumb but my first thought would be to compare the milling of the old vs. the new and see if the crush is actually the same. Maybe the new has slightly smaller or otherwise different structure. Maybe the husks are less brittle / more flexible.

And I think perhaps I would also do my own independent analysis of the grain in other ways to make sure it really is as similar to your old stuff as claimed, although I have no idea how you do that. But that's your job LOL.

[evily]

Perhaps dumb but my first thought would be to compare the milling of the old vs. the new and see if the crush is actually the same. Maybe the new has slightly smaller or otherwise different structure. Maybe the husks are less brittle / more flexible.

And I think perhaps I would also do my own independent analysis of the grain in other ways to make sure it really is as similar to your old stuff as claimed, although I have no idea how you do that. But that's your job LOL.

Thanks mashani! The milling of old vs new was my first thought as well. As for the grain analysis, yeah, I have no idea how one does that either, but I'm sure we will learn!

[LouieMacGoo]

The milling of the grain is a really good thought.

My first thought was before you even use the new grains that there should be some type of side to side test batch comparisons to ensure that the efficiency and quality of the new grist was comparable to what was currently being used. If those test batches proved no loss or issue with efficiency or quality then make the changes to the new supplier. I would then make sure that the processes had not changed. Sometime people take it upon themselves to "tweak" things when there is a change in supplies thinking they are improving the process when in fact then are not looking at the whole brewing process for the down stream effect. After that I would make sure that the equipment was functioning optimally and that there wasn't any failing pumps, filters, thermometers, heat sources or other mechanical failures that might be contributing to the inefficiency.

My dad always taught me when I was working on cars was to look for the easiest things first to rule them out and move to the more difficult/costly solutions to fix.

[mashani]

I have to agree with Louie that you do also have to weed out other potential variables / tweaks and be sure you are really comparing apples to apples.

Although I don't know why someone in your world would mess with multiple bits of the process at a time, it defies "scientific method" which I would think all pro-brewers at your scale should be following. But you never know.

[Inkleg]

Shower! That's all I got.

Like Dave stated crush would be what I looked at first. Even though malt analysis is close, where it's grown and how it's stored may come in to play as it is conditioned and crushed.
When was the last time all measuring parts of the machinery were calibrated? Has something changed in the water supply?

Is someone skimming wort for personal use? Do hops mysteriously disappear? (If so suspect Beer-lord)

[Beer-lord]

Guilty!
I love this discussion though I don't have anything different to add.
Great stuff!

[The_Professor]

I have to agree with Louie that you do also have to weed out other potential variables / tweaks and be sure you are really comparing apples to apples.....

My first thought was before you even use the new grains.....

Malt Extract Loss Case Study
You are the brewing manager responsible for the operation of a brewhouse of a 200,000 bbl brewing operation. Recently your brewery shifted malt suppliers. The malt you were receiving and your new malt supply had similar malt analysis and was also similar in the barley varieties. When you started using the new malt you noted a significant drop in recovered extract in the brewhouse. Explain what approach you would take to identify, verify and correct this loss of extract.

Yeah, although Louie skips the actual scenario of "When you started using the new malt you noted a significant drop in recovered extract in the brewhouse." by saying ".....before you even use the new grains.....", mashini summed it up and presented what I would have said as well. Just because you are presented with the case that it happened after you started to use the new malt does not mean you should not confirm all procedures and equipment are the same (no repairs, replacements, new employees) and that all recorded brewing stats (including the times and ways they are collected) do indeed point to the malt only as the cause. My thoughts about the malt would include crush (as mentioned (another possible equipment/procedure issue) ), age, and verifying the stats (done where by whom in what time frame). And if there were indeed checks that pointed to the malt being okay before brewing a 200,000 bbl batch why do you suspect the malt or where was the error in those procedures?

[RickBeer]

Since the class is on the science of the brewing process, I would lean to the grain having a different moisture content that impacts the throughput. Or what Mashani said first. Or "Evily is stealing wort"....

[FedoraDave]

Malt extract loss, huh?

Have you looked under the couch? Sometimes stuff just rolls under there, and you find cat toys, loose change, malt extract....

[Dawg LB Steve]

The efficiency of extracting the usable sugar really can come from maybe that new strain of grain being a bit smaller going into the same mill thereby lowering the efficiency, also to consider the new supplier's malting process, is the maltster letting the acrospire get to the correct size before stopping germination, is the drying process the same as the old supplier, drying temperature to high to destroy some of the enzymes needed to convert? So many things point to the malting process. May need some amylase enzyme to help with conversion with the new grains.
I am not a scientist, but I did stay at a Holiday Inn once or twice. Just some things that I have picked up in researching this hobby.

[mashani]

Maybe the "disruptive brewing division" is stealing the wort and adding more hops.

Well, we can wish?

[RedBEERd]

Maybe the "disruptive brewing division" is stealing the wort and adding more hops.

Well, we can wish?

Nice!

We have a winner.

[ScrewyBrewer]

And here is my team's particular problem to solve:

Malt Extract Loss Case Study
You are the brewing manager responsible for the operation of a brewhouse of a 200,000 bbl brewing operation. Recently your brewery shifted malt suppliers. The malt you were receiving and your new malt supply had similar malt analysis and was also similar in the barley varieties. When you started using the new malt you noted a significant drop in recovered extract in the brewhouse. Explain what approach you would take to identify, verify and correct this loss of extract.

When you mentioned similar malt analysis immediately I thought of the DI pH value of the old and new malts. For instance at a high level, crushing 40 grams of any malt and stirring in 100 milliliters of distilled water produces a 1.2 qt/lb ratio mash. After settling for 20 minutes, the pH of this test mash will change, the darker the malt the lower the pH, the lighter the malt the higher the pH. The recorded pH value of the test mash is known as the DI pH value of the malt that was tested.

Unfortunately maltsters do not always label their malts DI pH value accurately, or in some instances make that data readily available to brewers. To further confuse things the same type of malt, from two or more different maltsters, can have widely varying DI pH values. The differences in the malt DI pH values, used by the authors of many popular brewing water calculators, is the reason why their calculators provide different mash pH values. Since mash pH affects brewing efficiency and there are DI pH differences between malts and maltsters, I would first run a DI pH test to see if that was the cause of the efficiency differences.

[Whamolagan]

Wouldn't the dirt that the grain was grown in have some variable? I am no expert in malt in any way, but I did study botany in college (the brief time I was in college). I have grown a garden every year for the last 20 years. I make my own dirt, and have to customize for different plants. I have grown the same kind of chilis in 3 different mixes of dirt, and in no way were any of them the same. Just my 2 cents worth, but it has been proven that Tabasco peppers grown in Louisiana give it that taste, in the 90s they tried to open another plant, I believe it was Indiana and the peppers they grew there were different due to the dirt grown in.

So if the PH of the dirt is different wouldn't that change the ph of the grain?