Ep 18 - Can You Solve This Issue??

In a new one-off format, I go solo on the show and share with you all the details of a real world brewing problem to see if you can solve it.

You will get the breweries problem as it was described to me.

A full understanding of their CIP routine, their yeast and fermentation practise and the actions they took to help diagnose it.

What do you think caused the issue? And how would you solve it?

🌱 Simpsons Sustainability Report
🎥 Sustainability Without CAPEX Talk
📨 chris@brewresourceful.com
💼 My LinkedIn
📷 My Instagram

Transcript

0:14

Hello everyone and welcome to the latest episode of the Modern Brewer Podcast with me, your host, Chris Lewington. So this episode is actually going to go in a bit of a new content style. It's not going to stay forever. I just kind of want to do it for one episode. But I've been thinking, is my content super interesting and engaging? I hope so. But ultimately a new fresh look and maybe a new emphasis might bring a little bit of, difference to the people who listen to this regularly. so with this, what I'm going to do is I'm going to basically present you a real life brewing problem. it's very recently. came into my path and it has been solved. So, what I'm going to do is go over this real brewery problem and give you all the information that I basically had, to see if you can try and solve it. I think problem solving is probably one of the most fun and always the most stressful part of being in a brewery. So, I really hope that this episode acts as all of the fun of problem solving with none of the stress, as ultimately this is not going to be your brewery. Firstly, just a big thank you to everyone who turned up at the BRX talk. it was really great to see so many people that I knew both in the show and in the crowd and just a bunch of new faces. a big shout out to Steph from Murphys who was of course, With me in the entire presentation. she is an excellent excellent brewer and a really good person So i'm really glad I got to share the stage with her And I thank to everyone who came off afterwards and sent some very kind words to both me and Steph I Was supposed to live stream it which was kind of entertaining because I couldn't get the live stream to work, which is totally my bad So what i've done is i've Put the talk on YouTube. So we've got the majority of the talk videoed nonetheless, and I've posted it on YouTube. So I'll stick a link to that in the, uh, show notes. If anyone is interested, it is not about the Modern Brewer podcast or that it is. Naturally mentioned. Uh it's gonna be a brew resourceful and the topic is sustainability without CapEx. So, yeah, big shout out to everyone from BeerX. It was such a fun occasion as always and a big one for me personally because I came back from the Caribbean last year and basically launched Brew Resourceful and to podcast at that time. So, uh it's a really nice milestone for me to look back on. So, yeah, a great event and I hope everyone else had a lot of fun. Before we get into the episode, I want to take a moment to talk about friends of the podcast, Simpsons Malt, the largest family owned malting company in the world. Their 160 year passion for quality has given them global respect amongst both the brewing and distilling communities. As regular listeners know, I am a huge champion of sustainability and Simpsons Malt's 2023 sustainability report highlights the company's outstanding commitment to people and the planet. one of the biggest takeaways from the report for me was actually the vertical integration of their supply chain. This incredibly unique approach to malting means they forge long term relationships with their malting barley suppliers. By working directly with them, shortening the traditional molting supply chain to simply farmers, maltster brewers. I mean, having long-term relationships with their farmers makes total sense, right? It means Simpsons Malt has total control over the barley that enters their malting sites and also enables them to work with farmers to drive sustainability throughout the supply chain. I'm going to link the sustainability report in my show notes, please check it out. And remember, choosing suppliers who are reducing their emissions in turn reduces yours. Okay, back to the episode. I'm going to take you on a journey through an interesting problem with the information presented as I heard it. This is a real brewery problem that did cause a lot of financial and emotional damage to the brewery. So whilst it is really interesting and it is a good case study, please always be respectful when talking about issues in other breweries. It's so easy for us to sometimes scoff or think that we would just do things in a different way, but we all know how things happen in breweries sometimes and we should always be respectful of others and also be thankful that this brewery is going to share this information with us. I really hope this episode sparks the intrigue of the great brewery minds that listen to this podcast but also helps prevent similar issues and sparks more open discussions on what happens in breweries issues and how we solve them before we get into the issue at hand. Firstly, I just want to make sure that everyone knows I was not working with or for the brewery in any capacity when this happens. It's just a friend's brewery that I'm privy to the information and they very kindly let me share their problem as a way to help the industry. So with that in mind, you the listener will play the role of a brewery consultant who often gets these exact type of issues with this level of information and your worth as a brewery consultant isn't solving it. As a brewery consultant, the information is not as complete as if you are in the brewery yourself. So there will be some missing gaps and blanks that you will have to fill in and make some assumptions. That's the life of a consultant. To be clear, I will present the information to you as it was presented to me. So there's no hidden clues, and I'm not trying to mislead or trick you into a certain way of thinking. Just be open minded and enjoy all the fun of problem solving. future brewery consultant, and remember that as a consultant, you shouldn't take everything at face value I've made this episode purposefully short so you have time to listen to it twice and digest all the information properly. Okay, so here is the issue. A brewery has just contacted you and says, I have a peculiar problem with one of my tanks and would really appreciate any help. I have now dumped three batches from FV1. The first batch was a lager and everything appeared normal until lagering time. When I picked up some sort of isoamyl acetate smell and taste. Gradually worsening every day until it became quite solvent y. I put it down to bad yeast supplier, did my normal CIP, and brewed a pail into the same tank. All fine during fermentation, until a cold crashed to 12, where I dry hopped and noticed that that same isoamyl flavor was coming back in. I reckon I have an infection, so I dump this batch. What's interesting is, I use the same, Batch of dry yeast into a different tank and had no issues. So on FV1, I broke down all the components on the tank, full nitric CIP, and then I brewed another pail with the same recipe into that tank. At 12C it happens again. So at this point I send some samples to Murphy's for an external microanalysis. No wild yeast or bacteria. I dumped the tank. Beers were in fizz can spec before they were dumped, so the pH and gravity were fine, but the sensory is the issue. The isoamilacetate banana pear smell that eventually became solvent y. The pails in question were dry hopped at 9 grams per litre, and strangely there was no perceived hop aroma, which is a large deviation from the standard of this recipe. Okay, so this is your first information received and you probably already have a hundred ideas or maybe one or two clear or maybe none. And that's absolutely fine because we're going to go through a bit more information. A lot of it came through about a week later, as often with brewing, you, what happens in day one, your problem you find in day one, you have to wait weeks to reappear. this is where I think the most stress and problem solving comes out. If you're making something like soda and you can just redo batches, it really feels, like everything can happen much quicker. But with brewing, It can be a long slog until you get that sorted. Okay, so a week later, the problem has now intensified. we brewed with the yeast crop of the first dumped pale from FV1 into FV2. As they didn't detect the issue until cold conditioning, a repitch of this yeast is totally normal. The FV2 pale is a different recipe dry hopped at 20g per litre. At cold conditioning, this batch in FV2 is now showing exactly the same sensory issues during cold conditioning with no measured deviation in pH, gravity, or temperature. Again, this batch was reported to have little to no hop aroma despite the 20 grams per liter dry hop. Again, a very large deviation from the normal recipe. During this time, There has actually been two successful batches separate to the dumped batches which have passed the sensory and made it into pack as normal. One was a lager in FV5 and another was the same recipe as one of the dumped pails with a 9g per litre dry hop. This time into FV4. The successful batch's yeast was re pitched into a different pail, a 20g per litre dry hop, into FV3. This subsequent batch had the exact same sensory issues as the previous dumped batches, and again, no perceived deviation in gravity, pH, or temperature. Interestingly, the batches that have been dumped The three in FE one, the one in FE two, and the one in FE three were reported to have quick fermentations reaching terminal gravity one to two and a half days quicker compared to a usual fermentation. Okay, so this is the majority of the issue for now. I will now share with you the brewery's CIP routine, their standard procedures, and their standard yeast and fermentation procedures. Okay, so an overview of the CIP routine. The CIPs go through a pre rinse step, a caustic step, another rinse, and a parasitic active cycle. There are no holding vessels, so all CIPs are pitched and ditched. All water is 100 percent RO. There's nothing really to note on the pre rinse steps, pretty standard. Caustic concentration is 4 percent V to V, with a 32 percent caustic product used. And the foundation water is meet, flow metered in. the caustic steps, are conducted at 60 to 70 degrees and last for at least 30 minutes. The pressure to the spray ball is greater than 0. 8 bar and the rinse steps after the caustic cycle are validated with phenolphthalein. Once that happens, a peracetic acid step is added for 15 minutes at at least 150 ppm and this is validated with PAA strips. The tanks do have a side manway. The seals for this are scrubbed and soaked in the same caustic solution that is used for tank CIP. The sample taps are opened but flows are reported as weak and intermittent. FV1 and FV2 have static spray balls and the others, FV3, have rotary spray balls. The brew house is cleaned weekly using a similar caustic procedure and parameters as mentioned before. The wort line is cleaned after every brew using the same procedures and parameters with the heat exchanger receiving forward and backwards flow during the CIP. There is no oxygenation stone. This, when used, is left cracked open for flow to drip through. is only six months old. As are all hoses used in the brewery. Okay, now let's have a look at what the yeast and fermentation standard operating procedures look like at this brewery. All original pitches are made with a hundred percent dry yeast from the same supplier. the work for dry yeast pitches are not aerated. The brewery does re-pitch their yeast. This yeast, this work is aerated with pure oxygen. There is no oxygen flow meter to tell you how hot it is. Much oxygen is in the worked. The yeast pitching procedure looks like this. First, they count the yeast at the bottom of the origin vessel. Then they calculate how much yeast is needed to achieve a specific yeast count in the destination tank and then pitch the calculated amount. This is then validated with a yeast count in the destination tank where the wort has finished casting out. They ferment, dry hot and cold condition. in the same tank. The tanks are just classic craft brewery cylindriconical vessels that are designed to hold pressure and are chilled with glycol through a single jacket with the inlet at the bottom of the jacket or tank and the outlet at the top. The brewery records the density, the pH, the temperature and the head pressure every working day of every fermentation. Their working days are Monday to Friday. They measure the density with an Anton Parr EasyDens. Great pieces of equipment, by the way. The pH with a pen pH meter, the temperature with one internal temperature probe on a tank which is located just above the cone, and the head pressure is measured with a pressure gauge which is fixed on the CIP arm. If you're like me, you're probably wondering what is the truth and what could be misinformation. And as a troubleshooting consultant, I would imagine this is pretty much the name of your game. Well, during this time, the brewery made some very smart decisions to validate their perceptions and measurements. Naturally, their results are integral to the origins of the problem. Firstly, they conducted microbiological analysis. of the second and third dumped batch. The sample was taken by the brewery at the cold conditioning stage. No reported anaerobic, aerobic, or wild yeast was reported by a trusted external lab. Also, sensory samples were sent for an external analysis. They validated intense isoamyl acetate, which is banana, ethyl acetate, which is solventy. They also noted intense mercaptan. By request, there was also validation that there was little fruit or citrus aromas associated with hops in both samples. One of the samples was dry hopped with a 9 grams per litre recipe, and the other one with a 20 grams per litre recipe. The brewery also compared their density and pH to known reference samples, which both proved that their density and pH meters were reading within an acceptable deviation. Pressure gauges are used interchangeably, meaning it is unlikely that they are reading incorrectly. A temperature validation was conducted by taking a sample from the sample tap and measuring it with a handheld temperature probe. This did show a three degree increase from the sample temperature to the reading of the probe located at the top of the cone. Right, so I appreciate there's a lot of information in there, maybe not enough, but quite a lot to digest. And there could be more questions than answers. But with this fairly limited information, you might not be able to rule out much. But, as mentioned at the top of the episode, you will need to make some logical assumptions to crack this case. And all of the information to find the right solution to this problem is here. So let's quickly summarize and then go through a timeline of events. There were five dump batches in total and two successful. Okay, so let's quickly timeline the events. First, there was a lager brewed into FV1. They it was a yeast supplier issue and dumped. They then brewed a pale ale into FV1, which was subsequently dumped due to suspected infection. There was an intensive cleaning process and the seals were all replaced. They then brewed a third beer, which was a different pale ale recipe, into FV1. This was then subsequently dumped as well. This is where the confusion started to step in. During this time, two successful batches with two different recipes and two different yeast strains From the same yeast provider were successful, one into FV4 and one into FV5. One was a direct dried yeast pitch, which was the lager, and the other was pale ale, was re pitch of a successful batch previous to when this issue started. After that, there was a pale ale brewed into FV2, with yeast from a previously dumped batch, that was then dumped. And then, finally, a pale ale brewed into FV3, with yeast from a successful batch. This was also dumped. All dumped batches have the same sensory issues. Three of the five batches had clean micro results, and the other two's results you don't have yet. The density, pH, and pressure have all been validated, but there was a three degree difference between the temperature probes and the handheld temperature probe. Okay, so, reckon you can save the day? What do you think is the reason for the dumped batches? And what do you think the solution is? As I said right at the top, I purposely made this episode short, so you have the time to listen to it twice. And I do recommend that you do listen to it again to make sure you catch all the information. And just to ensure that you do, I won't be giving you the answer until the next episode. But I would like to see who has solved the problem, and I'd love to know what conclusions you have come to. You can totally DM me on LinkedIn or Instagram, and I'll provide the links in my show notes. And I'll actually even give you three attempts to get the right answer. If you get the right answer, You'll get a mention on the next episode of the Modern Brewer Podcast. If you are listening to this episode and the next episode has already been recorded, please still do get in touch with me, especially if you have any questions, but of course you can find the answer pretty quickly. So that's actually going to do it for this week's episode. I really am excited to see how this style of content works and if it is interesting to you. For me, as I said, problem solving was my most loved and stressed part in brewing, so I hope this removes the stress and acts as a bit of fun whilst also reminding you of what can happen when things start to go wrong. To give you some peace of mind. The brewery invention did get the problem solved, and they are back up and running, and the brewery did not have to close. But let me tell you, these are the types of problems that really can cripple a small to medium sized brewery very quickly. Especially if you look at the quantity of hops being used in modern day beers. The cost of production just intensifies so much, you're so disappointing the stakeholders of the business, it can be an emotional disaster. So please, whilst this is fun, and I have mentioned this before, please respect the people who have these issues and also use this as a learning point for your future issues. What I would love from the listeners is just some solid feedback on what you thought of this episode and the amount of information and how difficult it might be to solve. And of course, if you listening have had any complex and interesting issues of your career and how you solved them, please let me know and you can come on and can discuss them on a future episode of the podcast. So that's going to conclude everything today. We'll be back next episode with the classic format and perfectly timed. It will be on sensory evaluation. So, thank you for listening and Good luck on your quest, finding the solution to this problem. Catch you on the next episode of the Modern Brewer Podcast.