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Brew Your Best Beer with Zinc Buddy
Category : Technical
Date : April 30, 2024
Author : Chris White, Ph.D
What Are The Improvements To Fermentation With Zinc?
Zinc promotes proper fermentation speed, attenuation, yeast health at the end of fermentation, and yeast's ability to perform faster hop creep. It also brings a better uptake of diacetyl and less acetaldehyde production.
Can Yeast Ferment Without Zinc?
Yeast can ferment without optimal zinc, so it’s very hard to see that it’s not optimal or how it’s missing in your fermentations. But when it is optimized, brewers find it helps fix occasional problems such as the off flavors with acetaldehyde and diacetyl, pesky attenuation, and fermentation issues. As well as it really aids in the yeast’s ability for protein synthesis and yeast growth, meaning healthy generations for those that repitch.
How Have Brewers Been Adding Zinc?
Brewers have either not added zinc or added zinc salts to the hot side, typically at the end of the boil. There are lots of old-time stories, such as adding pennies to the boil. The problem is that zinc chelates to proteins, which creates a strong covalent bond. The whirlpool removes a lot of protein in the trub, which is where most added mineral zinc is found.
We worked with Lallemand 20 years ago to release Servomyces, which is a yeast culture grown in the process of very high zinc, and the zinc is taken up by the yeast, then heat killed. When added to the end of the boil, the yeast cells protect the zinc ions, and they are taken up by the live cells pitched into the cold wort. Servomyces works great — but a lot of brewers don’t use it. So, we wanted to find an alternative that people could use just as effectively as Servomyces.
We worked with Lallemand 20 years ago to release Servomyces, which is a yeast culture grown in the process of very high zinc, and the zinc is taken up by the yeast, then heat killed. When added to the end of the boil, the yeast cells protect the zinc ions, and they are taken up by the live cells pitched into the cold wort. Servomyces works great — but a lot of brewers don’t use it. So, we wanted to find an alternative that people could use just as effectively as Servomyces.
What is Zinc BuddyTM?
BUY NOW
Why Add Zinc To The Cold Side?
If you add zinc on the cold side, there is a much better chance of the zinc getting to a yeast cell, getting inside the yeast cell, and contributing to the metabolism of the wort carbohydrates. By adding to the cold side, the proper concentration can be adjusted and added without worrying about hot side losses and a lower-than-ideal concentration of zinc. A lot of enzymes inside the yeast cell are zinc-dependent, so zinc needs to be there right at the active site when it’s taking substrate to a product.
For example, let’s consider producing ethanol. If you can drive the reactions to the final stage of ethanol production at the proper speed and timing, yeast will ferment more of the carbohydrates at the proper fermentation speed. They will develop new cells appropriately, and these new cells that are developed appropriately will be able to uptake the diacetyl that’s produced. They will be less prone to making acetaldehyde because they are healthy.
If There Are So Many Advantages On The Cold Side, Why Aren't More Brewers Adding It?
Historically, brewing practice has been handed down for generations, and yeast, of course, is added on the cold side, and that’s it. Most other fermentation industries add other things to the cold side, such as buffers, nutrients, and so on. However, the brewing industry has, for good reason, been more concerned about contamination and oxygen pickup when opening up fermentors. So, we have just relied on hot-side additions. But if you think about it, hops added on the cold side, dry hopping, is another form of adding something on the cold side. And what happens? Some diacetyl production is caused by oxygen uptake and hop creep, which is a little bit of fermentation from the bits of carbohydrates and nutrients coming from the hops. So, we’re already doing it for the most part. If you’re dry hopping, you’re adding something besides yeast on the cold side.
Why Not Just Add Zinc Versus White Labs Products?
Zinc can be toxic if not added at the right concentration (around 1ppm). Some zinc products, if added directly, can be very harmful and detrimental to yeast health. If you're using zinc in salt form, sterilization and acidification need to take place for it to remain in solution and keep contamination out. Proper equipment and knowledge of sterilization should be accounted for.
Zinc Buddy™ is made as a ready-to-use solution that takes the guesswork out of your cold-side zinc additions. Sterilized and acidified to a pH of 4 to ensure maximum solubility and uptake.
What is the dosage?
- Pro
This achieves 0.2 ppm zinc in cold wort at pitching time. It is assumed the wort has 0.1 ppm, so the total target starting Zinc is 0.3 ppm. Use the same for ales and lagers, in every batch.
Many brewers are now discovering the benefits of adding other things with the yeast right at the beginning of pitching, such as zinc, enzymes such as ALDC or Brewzyme-D, and Clarity Ferm. These White Labs products have been tested to White Labs standards for easy-to-use accessibility. Just spray the cap with isopropanol or sanitizer and loosen. Then carefully pour the desired volume of solution directly into the fermentor before knockout.
Calculate Recommended Nutrient Amounts For Your Next Brew
What Do You See In The Future For Cold Side Additions?
I think the brewer more and more might take two or three things along with the yeast into the cellar for pitching time. They will get it all ready and add it to the fermentor at the same time. We’re going to have to really focus on the homogenization of those enzymes and nutrients with that cold wort. Many small breweries add yeast to the top manway of the fermentor. But the most optimal way to pitch yeast and get the best homogenization is to add the yeast in-line on the way to the fermentor, but most people don’t have that ability or that practice.
One way to do that is with our FlexPump, a peristaltic pump that’s designed to add yeast in-line on the way to the fermentor. With this pump, one could not only pitch their yeast for maximum homogenization but also add nutrients and things like purees in line. If you add it to the top of the fermentor, please do so as early as possible during the transfer. Mix well because enzymes and nutrients aren’t going to grow. They need to be well mixed to encounter the components they need to do their bio-activity.
Clarity Ferm is a good example of that. When people are using it to reduce gluten, they can have mixed results if they’re adding it to the top of the fermentor because of that mixing or lack thereof. We have some turbulence from the yeast growth and the fermentation. But it’s a different gravity than what you’re adding with the enzymes and nutrients. So, the mixing is not as complete as it would seem. And so you have much better results with Clarity Ferm, for example, when you’re adding it directly in-line into the fermentor and getting it well homogenized. So, whatever way you do that in your brewery is going to give you the best practice results. The same is true with zinc.
One way to do that is with our FlexPump, a peristaltic pump that’s designed to add yeast in-line on the way to the fermentor. With this pump, one could not only pitch their yeast for maximum homogenization but also add nutrients and things like purees in line. If you add it to the top of the fermentor, please do so as early as possible during the transfer. Mix well because enzymes and nutrients aren’t going to grow. They need to be well mixed to encounter the components they need to do their bio-activity.
Clarity Ferm is a good example of that. When people are using it to reduce gluten, they can have mixed results if they’re adding it to the top of the fermentor because of that mixing or lack thereof. We have some turbulence from the yeast growth and the fermentation. But it’s a different gravity than what you’re adding with the enzymes and nutrients. So, the mixing is not as complete as it would seem. And so you have much better results with Clarity Ferm, for example, when you’re adding it directly in-line into the fermentor and getting it well homogenized. So, whatever way you do that in your brewery is going to give you the best practice results. The same is true with zinc.
- TECHNICAL
- April 4, 2024
