Hard Seltzer News recently interviewed Ashton Lewis, Technical Sales Manager for Brewers Supply Group (BSG) and Kain Escobar, Manager of Brewing Research and Ops, Rahr Eagle Brewery & Rahr Technical Center.  This is that entire interview transcript, where the brewing experts talked about secrets to brewing world-class hard seltzer.

HSN: Starting with Ashton — could you introduce what Brewers Supply Group is and what you do? What size brewers are your customers? 

Ashton: Yeah, Brewer’s Supply Group, or BSG as we’re commonly known, is owned by Rahr Malting Corporation, and Rahr Malting has been in business since 1847. We’re currently headquartered in Shakopee, Minnesota, and our campus in Minnesota was first built in the late 1930’s following prohibition. So, what BSG is — we’re a distributor. We distribute a very wide range of malting products, hops, yeast, specialty ingredients, adjuncts such as different fermentable sugars and process aides for the brewing industry. So, I like to tell people that BSG supplies everything to breweries but water for [the] production of beer. We also have a division that handles wine ingredients, we service distilleries, and we also have a part of our company that deals with homebrewing through supporting our distributors in the market. We don’t sell directly to homebrewers, but we sell to the retailers’ side for homebrewing. In the United States, we actually have nine warehouses in the U.S., so we have nine distribution centers in the U.S. and three in Canada, and then Rahr Malting operates two campuses. We have our Shakopee campus for malting in the United States and then we have our Alix malt house in Alberta, Canada.   

HSN: This one I’ll ask — just so I can get your thoughts — let’s start with Kain. What are some frequently asked questions you’re getting about hard seltzer from clients?

Kain: I mean the biggest is how to make it, right? [Laughs] You’re hearing that everywhere. But besides that, it’s what nutrients should we use? What should we ferment out of? Do we need carbon? Do we need to filter? All these things are just popping up all over the place. People aren’t really comfortable with it, so it’s kind of that odd man in the room, and they don’t really know how to approach it.  

HSN: Ashton, did you have any thoughts on what are some of the frequently asked questions that you’ve been getting?

Ashton: Yeah, so our relationship with BSG and Kain and the Rahr Technical Center…Rahr Technical Center kind of supports BSG like we’re the customer. So, a lot of the questions that Kain and the group at the RTC get come from us people in the field — the virtual field these days. A lot of the questions we get are, like Kain said, [sic] related to how do you make them, [the] nutrients that are used…If we back up a couple [of] steps, I think a lot of brewers think that making seltzer — because seltzers are clean and clear products — that if you take sugar water and ferment it, it just magically comes out this clear, neutral base, and that is so far from the truth. So, [for] a lot of brewers, the question is: Well, I started off with sugar water, and I added yeast to it, and it turned out…it was terrible, it smelled like sulfur, or [smelled] weird or it didn’t ferment. So, some of the questions are like, why didn’t it ferment? Or, it fermented, but it smells like a rotten egg. What happened? And then we get beyond that, because there are things we can do to help with those questions, then it becomes more nuanced, like, how do we clarify it? Can’t you just let it settle and it just turns into water? No, it doesn’t work like that… Or, ok, we’ve clarified it. Now what? You know, how do we add flavor to it, and how do we make this neutral base into something that tastes like a lot of other products that we have on the market? So, it’s really kind of a progression. As brewers start to do more and more with seltzer, their questions actually become more advanced and deeper the cleaner it gets. So, the closer to neutrality, the more questions that follow.

HSN: So you talked about how people are thinking because they are fermenting from just cane sugar that it’s going to magically turn out clear or…the thing that people don’t understand is that cane sugar doesn’t necessarily have the same nutrients as malt. So, what kind of yeast variety works best for hard seltzer, and what can brewers who don’t want to use malt as a base, what can they do to get the nutrients needed to ferment their seltzer properly?

Ashton: Why don’t you start out with that, Kain?

Kain: Alright, so, it’s kind of player’s choice. I don’t want to say there’s one specific yeast or one specific nutrient that is, hey, this is the holy grail [that] will solve all your issues. You really have to fine-tune your process and figure out what works best for you. If you’re trying to use a house strain, then there you go, that’s your yeast out of the equation. Now, you have to figure out your nutrient and your substrate to make that work, right? I have had a lot of experience with some of the Bevie products, and I’m not just saying that because we sell them at BSG — in my former life as well. They work great. They are excellent tools in your toolbox to utilize and get that outcome that you want. Bevie’s got a new yeast nutrient that I’ve been playing with lately, and it’s been phenomenal. We’ve made some seltzer base using our US-05 fermentis yeast, and it performed just like the turbo yeast did. So, we’ve got a couple more hoops to run it through as far as flavor and analytics, but so far, how it’s performing — it’s doing very well. At the end of the day, you just have to get something that works for you. There [are] a [lot of] different yeast nutrients on the market right now. There is no…Hey, this is how much you have to add because [there are] too many variables. One, what kind of sugar are you using? Are you going straight dextrose, or are you using sucrose? Are you using Globe 55, which is a blend, or are you going malt-based, right? So, if you’re going to malt-based seltzer — which is what I’m drinking now– then you really don’t have to worry about that because you’re getting a lot of those nutrients [sic] coming from the malt. So, it’s very very dependent on the process. Think of it as more tools in your toolbox. 

Ashton: You know, from the sales side — So, Kain’s office is in our research center and they have a pilot brewery and lots of analytical equipment for process testing, and then they have a basic research lab. A lot of tools that are at their disposal at the lab, so if we’re looking at what kind of yeast you want to use, you’re going to want a yeast that’s going to ferment…it’s going to functionally perform…Typically, people want to have a relatively rapid fermentation that’s also clean, so it needs to ferment; it needs to do it quickly, cleanly, reliably. In order for that to happen, you have to have nutrients. So, Kain and the group in the RTC, they’re able to use different nutrients and use different yeast strains, and they have the analytical tools to basically produce a clean beverage from different inputs. But, that’s the key to me is [that] the desired outcome is a clean beverage. It’s not like we’re making pilsner, and Helles, and pale ale and IPA. The yeast is something that’s going to make these beers different. With seltzer, the outcome is pretty clean. So, the way I look at it [as] a salesperson is that if our customers can buy a product that’s reliable, that they don’t have to be a scientist to figure out how to produce the product, that’s going to be easier for the user. And the products that Kain mentioned that our sister company, Bevie, in England produce — they’re yeast that have been selected for performance and then they have nutrients that have been developed specifically to enable the yeast to quickly transform basically from a nutrient free substrate into something that’s clean and useful for the seltzer product.     

HSN: For Kain, do you find that brewing seltzer from malt is a little more approachable than cane sugar, or do you think anyone starting out can figure it out with the proper guidance?

Kain: I think the idea is more approachable. Brewers have been doing it for years right? We’re making beer. Whereas the sugar substrate is a little different, you know, it’s a different animal. I actually find it harder to make a malt-based seltzer. It’s a lot easier [with sugar], more economical, and depending on how you’re doing it, your volume coming out the door can be increased very easily. And, so, it’s a little bit of a different animal to deal with straight malt. So, we’re actually doing some studies right now on that to try and kind of fine-tune our process to be able to do an 80% malt to sugar blend. But, it is definitely in my opinion [sugar is] more approachable and easier to attack the seltzers, you just need to know which way to attack it right? So, have all the right tools in hand to be able to execute that. I think overall it is kind of in a mindset, again, it’s easier to grasp your hands around malt-base, but it is a little trickier. 

HSN: Following up with that, what are some of the taste differences that people can expect between the two different bases — cane sugar or malt base? Is that something that they need to take into account depending on what flavors they’re planning to use, do you think? Like, what are those taste differences?

Ashton: When I think of seltzer…I’m going to approach it from a kind of the craft brewing and homebrewing side, if you will. When I think of a seltzer, I really think of a mixed drink. I think a seltzer is kind of a version of a simple cocktail. It could be a vodka tonic, gin and tonic, with maybe a little bit of lime in it. And, you can have advanced cocktails that would be more like a margarita. Maybe it’s got a little color or some cloud to it. Again, citrus and acid, but to me, that’s what a seltzer really is. And then, if you start blending in malt, you bring in flavors that are really not typically found in cocktails. So, a lot of the breweries that are making seltzers that contain malt, the reason that they’re using the malt is for tax reasons, for legal requirements, and the legal requirement for malt on the federal level has dropped to almost zero. On state levels, different states have different laws that sometimes are more restrictive than the federal — the TTB laws — but a lot of breweries that I’ve talked to that have malt in their seltzer, they want the flavor and the color to disappear. And, I think Kain has some real practical experience maybe with that topic.

Kain: I mean, it also depends on what kind of seltzer they’re making, correct? You’ve seen a lot with the increase in the craft movent of the seltzers, you know, seltzers with colors now. They’re not just colorless. You’re seeing greens and pinks so some of those can…those attributes from the malt can be hidden, especially with the number of flavors people are throwing in seltzers. It’s not just like sparkling seltzer water, plain. There’s usually going to be a flavor associated with it. Or, now juices and things like that being added to the mix. So, a lot can get covered up, and you can really get away with making that a kind of clean base with malt.       

HSN: From a sales standpoint, Ashton, what kind of equipment should a hard seltzer brewer have? What do you recommend, and does it differ much from a standard beer brewing set?

Ashton: I’ve been in the craft brewing industry for a long time, and when I was a kid, back in the early 90s, breweries had filters. And, that’s a thing that a brewery would always have, you know. It was like to say you had unfiltered beer for a craft brewer was odd, and the unfiltered beer may have been hefeweizen or an American-style unfiltered wheat beer. But, we certainly didn’t have Keller Pils and all of these unfiltered ales. So, I think a filter is pretty important for a beverage that — in the exception of cloudy seltzer — the seltzers that began the White Claws the Trulys of the world, they were clear. So, I think having some type of filtration [sic] filter whether its lee filter or a sheet filter or a lenticular filter, [it’s] a really good thing to have. It’s not required, but it’s nice to have. It’s also not required to use RO water — reverse osmosis water — but, with something that’s so clean and [sic] supposed to be kind of neutral, having fewer variables on the water side makes it easier. It’s not required, but it’s easier. So, I think either really clean water or RO water makes it easier. You do need to sterilize your sugar base, so you can just use a brew kettle and a typical wort cooler for cooling. Normal fermenters are fine. One thing that actually is different right now is, I think that a lot of brewers — and we’re learning from our work and the RTC and our colleagues in England — [realize] that oxygenation levels do make a very significant difference on the cleanliness of the fermentation. So, some way of aerating or oxygenating wort…and the clarification is really important. Now, if you’re in some breweries that are looking to have the residual sweetness — maybe they back sweeten or they’re adding sugars that could be fermentable, which is not the norm for seltzers — but, if a brewery is doing that, then they really really need to think about stabilization of their product either with something like a sulfite or a benzoate product or pasteurization. 

Kain: From a brewer’s perspective, there really is no difference [between] a regular brewery to a beverage plant or a seltzer production plant. You’re essentially just cutting your brewhouse in half, starting from your kettle back. So, you no longer need that front half of your brewhouse to produce it. Added equipment, to Ashton’s point – filters, in my opinion, are critical. You know, you want your product to be brilliant, so a filter is key. Oxygenation — I know a lot of guys have set up for compressed air, most of the time that’s not going to cut it. You know, maybe if you’re using a house strain yeast. If you’re using someone’s wild champagne-style turbo yeast, your regular aeration is not going to cut it. It needs to be straight O2 in order to hit those higher levels. And then, high gravity brewing is big. If you have the ability to make high gravity products, just think about it this way: The expansion rate is going to give you more volume out the door. Not only that, if you have the ability to cut it down with your target specs, you kind of muddy the waters and blend in some of maybe the imperfections you could have. Just say you have a little bit of a color tinge from your malt. If you’re using malt, then, think of it this way: That color is getting cut by whatever you’re cutting it by. If there’s a two-fold expansion, that just got cut in half…You don’t need a 50 – 100,000 dollar piece of equipment to do it. You can do it the poor man’s method, in a tank. Just have [a] designated tank for it, and you burn up some CO2, but it’s easily done.

Ashton: And to follow up on that, Kain, isn’t it the case that some of these yeasts produce a cleaner product if you go high gravity and dilute vs …?

Kain: Yeah, so, it is yeast dependent. So, some yeasts are a little happier at a higher [gravity], and that also makes you happier because that’s more product out the door for you.

HSN: I was going to ask about the challenges if a brewer wants to use real fruit juice flavorings. In terms of preserving that, how do you keep that shelf-stable?

Kain: Yeah, so again, the issue with that is possible hand grenades right? [Laughs] But, the reality is [that] you’re adding sugar to a possibly unstable product. A lot of the smaller guys don’t have the financials to have a tunnel pasteurizer or a flash pasteurizer. So, at that point, you may still have residual yeast or maybe even a micro problem. That may chew up that residual sugar that you’ve just back added and could referment in the package. So with that, you could also add your preservatives, but that is not a cure-all. It’s just a patch on a wound, essentially.

HSN: We wanted to kind of talk about vegan fining agents…

Ashton: Well, that’s actually kind of an interesting topic unto itself, but the most common vegan fining agent right now used for beer is silicic acid. And, the silicic acid conversation is a little bit of an unusual conversation because silicic acid solutions were really developed to help chill stabilize beer, so they were kind of developed as another type of like a silica gel. And, as it turns out, if you add silicic acid to beer, it helps clarify the beer. I don’t think the chemistry is that well known. It’s different than isinglass interactions with yeast cells, but the long and short of it is if you add silicic acid as a liquid to beer, you get clear beer or fairly clear beer. And, there are a lot of breweries that are using silicic acid to clarify beer. But, there’s actually a section of the CFR — code of federal regulations — that states that if you use silicic acid as a clarifier for alcoholic beverages such as beer and wine, [sic] you actually have to filter out the silicic acid as part of your process. The definition of “filter” is not part of the CFR, and [there are] actually no limits that are even stated as allowable in the finished product. So, that’s a long way of saying that a lot of breweries are using silicic acid to clarify beer, and they’re also using silicic acid — we have a product called Biofine Clear — that’s a trade name. A lot of our customers use Biofine Clear to clarify beer, and they’re also using it to clarify seltzer. The interesting thing about seltzer is that [in] some of the yeast strains that are used, some of the cells that are used are really, really small. In comparison to typical [beer] brewing yeast cells — [those are] usually around the five to 10-micron range — some of the yeast cells in these mixes [used in seltzer] are much, much smaller. And, I don’t know if the size of the cells has anything to do with it, but the clarifier like the silicic acid, like Biofine clear, doesn’t work too well on some of the products that are used for seltzer. There’s also a product — the trade name is called Chitosan — and it’s a chiton that’s derived from shellfish, and I don’t think vegans would consider Chitosan a vegan type clarifier. But then, that brings up the whole question of is the protein even in the beer to begin with? And, even if you used isinglass, the isinglass collagen doesn’t exist — is not detectable — in a finished beer. But, the answer is silicic acid is the most common.   

HSN: I wanted to wrap up the interview and just ask you guys if there’s anything else you wanted to add…

Ashton: Oh! I want to bring up a point here. So I’m going to be the interviewer here.

HSN: Ok!

Ashton: Kain, can you comment on [sic] sulfite levels in seltzer products, the legal limits through natural fermentation and how sulfite is measured in the laboratory? 

Kain: So, 10 BPMs would be the legal limits in the States. [There are] a couple different ways to go about it. You can kind of go the old, dirty, wet method, pararosaniline. [There are] scalar methods. [There are] a couple methods out there to actually measure. A lot of them are going to require an expensive piece of equipment, right? Probably the easiest would be [the] EBC pararosaniline method. The only downside to that is you do have some nasty chemicals that you have to deal with, and some of the shelf life on those chemicals aren’t the longest. So, unless you’re doing a lot of repetition and runs, it’s not completely worth it. But, there are a lot of outside source companies that are doing testing for that, so you can send samples in. It’s very important that people start kind of looking at it. There is kind of the free SO2 and the bound SO2. Just because you smell maybe an NH2S, a sulfur compound, doesn’t mean your levels are above those 10 BPMs. Now, just quite on the opposite side, you may not smell anything, but your SO2 may be above those 10 BPMs. It’s very important to have happy yeast. So, your nutrient, your O2, your fermentation temperatures — that’s all going to play on how that SO2 development occurs throughout the yeast metabolism. 

Ashton: I bring that up because, on the sales side, we tend to hear a lot of unusual questions from customers, but the topic of sulfites in seltzers is not something that we hear about. And, when I say sulfites in seltzer, what Kain’s talking about is natural from fermentation. Even with the natural fermentation by-products, there’s still limits on that, and we know that the pitching rate, fermentation temperature, the substrate type, the yeast strain, oxygenation levels, they all factor into the sulfite levels in the finished product. So, I think as brewers produce more seltzer, that that’s something that they really ought to be thinking about. Even if they don’t have the analytical equipment internally in their own labs, then sending samples out periodically for evaluation from outside laboratories is something that should be considered. 

Kain: Yeah, and kind of what I’ve noticed is that they tend to get a little higher levels with [sic] those turbo yeasts and champagne style, wine style yeast. There’s a little bit higher sulfite content, you know, up to 30 [BPMs] I’ve seen out there. So, keep your yeast happy. That’s kind of the biggest takeaway. 

HSN: Awesome. Yeah, it’s really interesting hearing you two talk. I’m just a homebrewer, so I don’t know too much of the chemistry side. Anyway, thanks so much for taking the time today to talk to me today for the podcast.

Ashton: Thank you for the invite.

HSN: Yeah, we’ve been getting a lot of owners of companies, [founders and CEOs] so it’s good to get the perspective of the real nitty-gritty of how these seltzers are made.

Kain: They’re simple, but they’re not simple. They’re very finicky creatures where you really have to fine-tune your process, everything from how you hydrate the yeast to if you have recirculation…How long are you recirculating? What kind of pump [are you] using to recirculate that? How fast are those RPMs working? Are you going to stress the yeast out? So it’s not clear cut.

HSN: Yeah, it sounds like the takeaway is keep your yeast happy! 

Stephanie Meade
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