New Wisdom for Yeast Starters

[Jack Arandir]

What's the collective wisdom about yeast starters now? I've been making 1.040 starters for years, but I hear people are trying 1.006 and other shenanigans. Chris White said lower sugar can be better for cell propagation, but I did not get a number. What have you done?

https://brulosophy.com/2023/06/01/t...veries-from-brewing-science-with-the-bru-lab/

 

[day_trippr]

I dunno about wisdom collective or otherwise but when I first started doing starters what I read was for reasonably healthy yeast to use 1.037 SG wort...

Cheers!

[edit] I could have done better than that

At the other end of the starter SG scale, when one is cultivating a pitch from bottle dregs, for example, the conventional wisdom is to do the first round with just 100 ml of 1.010 wort, then step the next round to 200 ml of 1.020 wort, and so on, until one reaches the 1.037 SG wort level and however many liters and cycles are necessary...

Cheers!

 

[DuncB]

I follow the advice on the Suigeneris website re growing yeast starters and it works fine for me.

 

[Bassman2003]

The low gravity starters are research experiments and apply more to large breweries. You are always ahead of the game by making a starter and growing up a lot of fresh yeast. No need to improve upon something that just works.

 

[day_trippr]

I follow the advice on the Suigeneris website re growing yeast starters and it works fine for me.

Never heard of it before but a short tour indicates it's a pretty robust brewing resource.
Bookmarked!

Cheers!

 

[CascadesBrewer]

There was a thread discussion about this topic. As I recall, the podcast discussion missed some important information from the research paper such as the need for a larger starter and the need for added nutrients (the nutrients used in the experiment are fairly expensive).
https://www.homebrewtalk.com/threads/fundamental-shift-in-yeast-starter-preparation.703741/

 

[Fhizzicks]

FWIW I have been using this technique for the past 6 months and have had great success; though, I'll note I've been using Cosmic Punch exclusively in that time, so it may not apply equally to all yeast strains.

I took the yeast cake from an early brew and dried it to use as my nitrogen source. When I need a starter, I mix up 2L of ~1.012SG wort to which I add ~20g of dried yeast. I give it a solid 36 - 48 hrs on a stir plate since at such low gravity there isn't enough activity to see a kraüsen rise and fall. I then pitch 1L into a 5.5 gal wort and save the other 1L for my next brew.

This is clouded by confirmation bias, but my beers have all fermented really well: fast and taste just as I expect them to. The overbuilt yeast that I place in the fridge also appear to last longer and come back faster than a traditional starter.

Before adopting this starter technique, I was already cutting down on my pitch rates and aeration levels since I was hitting FG within 48 hrs making it hard to time dry hop additions etc. So, the idea of having a slightly lower cell count (though at higher vitality) didn't bother me too much. My time to FG has only stretched out by maybe 6-12 hours, so I'm now just fermenting colder (~62F for this yeast).

 

[Bassman2003]

Thanks for sharing. Interesting about using the previous yeast cake for the nitrogen source. I wonder about sanitation in the drying process. What is your approach to dry the yeast cake? Just drain away all liquid and let it sit out?

 

[Fhizzicks]

Thanks for sharing. Interesting about using the previous yeast cake for the nitrogen source. I wonder about sanitation in the drying process. What is your approach to dry the yeast cake? Just drain away all liquid and let it sit out?

Because I boil the dried yeast with the starter wort, I don't worry too much about sanitation in the drying process. I just drain away the beer and place the yeast cake on a sheet pan in the oven at 150F for several hours.

 

[Bassman2003]

Thanks. So you basically cook the yeast then add it to your starter wort that is boiled right? Is that the same or similar to something like Wyeast nutrient that comes in the vial?

 

[PberBob]

I started using low sugar/high FAN starters a while back and have had good results so far. Those starters definitely wake up faster.

I have also been playing with making yeast extract for FAN. Yeast will undergo autolysis at 50 C (122 F) and pH 5-ish*. The first batch I overcooked/boiled into soup and smelled unpleasant. I let it ’mash’ for only about 2 hrs. The lower temp product from about 100 gm(1/2 cup) of washed yeast cake/starter slurry gets boiled with 60 gm of DME to make 2.5L of wort. That gets built into a 2-3 L starter with in 500ml increments to the initial live yeast slurry.

It does go slower initially and doesn’t get a high krausen (1-3 cm), but the optical density~cell density seems greater. It’s more labor intensive to keep feeding 1.015-ish sugar and shaking, but the uptake is fast after the first addition.

* Tanguler, Erten Utilisation of spent brewer's yeast for yeast extract production by autolysis: The effect of temperature, Food and Bioproducts Processing,Vol 86 (4), 2008, https://www.sciencedirect.com/science/article/pii/S0960308507000211

 

[PberBob]

I follow the advice on the Suigeneris website re growing yeast starters and it works fine for me.

Thanks for sharing that website- very rich info site!
I found that he also likes the 50 C autolysis recipe, too, and cites reasons.
https://suigenerisbrewing.com/index.php/2022/06/16/are-dead-yeasts-yeast-nutrient/Based on the plots in the Tanguler paper that plateau after eight hrs, with no points at shorter times, I’m guessing I have a pretty good yield at 2 hrs.

 

[dmaxweb]

I have a very basic question. The long time guidline has been a 1.037 SG starter achieved by a 1:1 ratio of DME to water. I have always boiled my starters for 15 minutes which results in about 15-20% evaporation loss. Should the pre-boil DME:water ratio be decreased to compensate for the evaporation loss? For example, for a 2 liter starter should the pre-boil ratio be 200g DME:2.3L water?

 

[CascadesBrewer]

I have always boiled my starters for 15 minutes

I have wondered about this fairly common practice. Pasteurization occurs in seconds at temps above 180F. Sometimes I just bring my starters to a boil, then cool them. Sometimes I let them boil for 5 minutes (just in case).

But I would say, yes, increase your initial water to target 2L of finished volume.

 

[uweschmitt]

I also wanted to try this method. Did anybody try nutrients like Whitlabs WLN 1000? And if you are using yeast extract: how are you dosing it?

 

[day_trippr]

fwiw, I don't boil my starters at all. Ever. I bring the water to a boil, turn off the burner, put the pot in the kitchen sink, stir in a drop or 3 of Fermcap depending on the volume (I often do 5 liter starters), stir in the DME, add the lid and turn on the cold water to fill the sink to cool to pitching temperature. Then I drain the sink, set the e-flask in the sink, add the yeast and pour in the starter wort.

It's already pasteurized by the time the lid is added, and doing everything potentially messy in the sink keeps the stove clean and The Spousal Unit pleased

Cheers!

 

[dmaxweb]

I also wanted to try this method. Did anybody try nutrients like Whitlabs WLN 1000? And if you are using yeast extract: how are you dosing it?

I bought 4oz of yeast nutrient years ago. It was from a very reputable local shop and the owner has since retired. I believe it was the L.D. Carlson product which he purchased in large packages and repacked for retail sale. I've been adding it only to starters at the rate of 1/4 tsp per liter. I'm still using that 4 ounce container. I have no scientific evidence pro or con. I've always had healthy vigorous starters and always decant prior to pitching.

https://www.northernbrewer.com/products/yeast-nutrient

 

[DuncB]

Measure water into kettle turn on.
Measure malt into pan. Add yeast nutrient.
Add boiled water and place on hob with barbecue temp probe in. Lid on.
Probe alarms at 83 c watch temp to 90c then turn off hob ( electric) so continues to rise to boil.
Leave lid on for five more minutes and then into sink cold water.
Prepare Erlenmeyer by boiling water in it and with stir bar in, whilst wort cools in sink.
Add yeast to Erlenmeyer add wort at correct temp in drained sink in case of spills.

 

[IslandLizard]

Prepare Erlenmeyer by boiling water in it and with stir bar in, whilst wort cools in sink.

Why not just use a sanitizer (e.g., Starsan or Iodophor, or both, successively)? Do you think boiling water in it offers better sanitation?

Also, boiling in flasks on a stove may cause a (big) mess and inconvenience one day...

 

[MaxStout]

Why not just use a sanitizer (e.g., Starsan or Iodophor, or both, successively)? Do you think boiling water in it offers better sanitation?

Also, boiling in flasks on a stove may cause a (big) mess and inconvenience one day...

And dangerous if done in a microwave. I stopped doing that a few years ago when I boiled some water in an Erlenmeyer. When I was taking the flask out with tongs, the water decided to erupt just then. It shot straight up like a cannon. Luckily, didn't get any on me, but it was quite startling. Superheated water from the microwave is not urban legend.

 

[dmaxweb]

I boil the DME, water, and yeast nutrient in large stock pot which reduces (not eliminates) the chance of a boil over. Typically 2-3 liters in a 12qt pot. When the boil is complete, I pour into a sanitized 4l Erlemmeyer flask sitting in a 6-8qt pot in the sink and then fill the pot with tap water. Once it's cooled a bit, I replace the tap water with ice cubes and replenish as they melt. This reduces the thermal shock to the flask going from boiling to freeze temp. I ONLY USE GENUINE CORNING PYREX FLASKS. They are much thicker and heavier than the knock offs. More expensive but much better than dealing with 3 liters of boiling hot sticky liquid.
I've never had a problem doing it this way but I'm not going to brag. Remember the Titanic was unsinkable.

 

[uweschmitt]

I also wanted to try this method. Did anybody try nutrients like Whitlabs WLN 1000? And if you are using yeast extract: how are you dosing it?

I meant the Low Carbon, High Nitrogen starter. The original publication uses yeast extrace (as described above). I wonder if I can use WLN1000 instead, resp. if somebody ( @Fhizzicks ? ) used yeast extract and in what quantity?

 

[DuncB]

Why not just use a sanitizer (e.g., Starsan or Iodophor, or both, successively)? Do you think boiling water in it offers better sanitation?

Also, boiling in flasks on a stove may cause a (big) mess and inconvenience one day...

I have a 3 litre flask and put about 15mm water in and boil that. The steam sterilises the bulk of it. No danger of boil over at all.
As I mentioned starter is boiled in a pan with temp monitor.
Boiling or steam stand a chance of sterilising whereas the chemicals sanitise.
I'd rather kill a few more bugs.

 

[IslandLizard]

Boiling or steam stand a chance of sterilising

Only at or above 250F/121C for 15 minutes.

Although I like the idea of steam "sanitation," I wonder if it is any better than a 10-15' StarSan and/or Iodophor soak.

 

[Red over White]

Only at or above 250F/121C for 15 minutes.

Although I like the idea of steam "sanitation," I wonder if it is any better than a 10-15' StarSan and/or Iodophor soak.

Technically, you could do both and not wonder. I believe both approaches have merit.

 

[day_trippr]

Although I like the idea of steam "sanitation," I wonder if it is any better than a 10-15' StarSan and/or Iodophor soak.

I have no doubt steam would be far superior to either Star San or Iodophor - or pretty much anything sane you could name. But it's a pita to use and can wreak havoc on vessels...

Cheers!

 

[CascadesBrewer]

Although I like the idea of steam "sanitation," I wonder if it is any better than a 10-15' StarSan and/or Iodophor soak.

People like overkill to make them feel good. If you are really that worried that you can not clean and sanitize a glass flask well enough with StarSan, then what chance is there for any of your other down stream equipment? I moved away from boiling in my flask partially because of too many stories of broken flasks (though I did that for many years), but also because it seems like a waste to pay $40 for to upgrade from my 1L flask, when I can get a 1 gallon jug for under $10 which has a nice wide opening for cleaning.

 

[DuncB]

This is comprehensive on the disinfectant/ sterilisation process.
https://www.cdc.gov/infectioncontrol/guidelines/disinfection/introduction.html
Interesting part about how effective microwaves are, I do use this to boil a little water in my 500ml Erlenmeyer for early prop starters. So I might achieve some sterility this way. My 3 litre can't fit in the microwave though.
A lot less faff than getting pressure cooker out for the small flask.
Oven for dry heat sterilisation seems most practical for my large flask.

 

[Yesfan]

This past starter I did a 15 minute boil and noticed I lost some volume (250mL). So I did a second step and just boiled for 5 minutes. Now I have a 3L starter of Que Bueno going now for a brew day tomorrow. Que Bueno puts out the rhino farts.

I usually just use dry yeast, but if I use liquid again I'm going to just boil enough to kill off the bugs and not lose volume like @CascadesBrewer or do @day_trippr's method to avoid a messy stove (and the wrath of SWMBO).

 

[Yesfan]

On a slightly off topic note, a dumb question.....

The last beer I used Imperial's Urkel on a Pilsner/Saaz smash. Unfortunately, I underpitched it (info: 4 month old pack into 4 gallons of 1.046 wert, pressure fermented @15psi @ 66F). The beer tastes decent, but there is an off flavor I'm detecting.

Can I use the slurry in a future batch or will that off flavor carry over? Even if I make a new starter from it?