How To Store Yeast Long Term – Shelf Life and Viability Test

It’s a common question when buying extra yeast (e.g. preparedness)… “How to store yeast?” or “How to store yeast long term?”

I’ve just updated this original post to better reflect the science, and the experience input from our readers. Continue to add your own opinions about storing yeast in the comments below.

>> jump down to storage tips

Maybe you noticed that your homemade bread isn’t rising as much. I recall when it happened to us awhile ago — A number of years ago I had bought a quantity of 1 pound instant dry yeast packs for preparedness. They happened to be Fleischmann’s brand, but yeast storage issues could potentially happen to any of them.

The yeast that I had been using was 4 years beyond the stamped date on the package. And the stamp date itself was 2 years after manufacture. So that means the yeast was 6 years old. Whoops. I hadn’t realized they were sitting on the shelf that long…

This prompted me at the time to go through our long term storage. I knew that I was storing a number of these 1 pound vacuum-sealed yeast packs. I found another that was 4 years beyond the date, and then found a 2-pack that was dated more recently (it was 2 years old).

So, I figured I would do a yeast efficacy test and compare the two! (A science experiment)

Is My Yeast Any Good? How To Test Instant Yeast For Viability

Add 1/2 Cup of warm water to a small bowl.

Add 1 Teaspoon of sugar and stir in till dissolved.

Then add 2 Teaspoons of yeast. Just dump it on top.

Wait 10 minutes.

It should have foamed frothy on top.

I took a picture. Here’s how it should look after 10 minutes:

How to test yeast efficacy

I tested the 2 year old yeast and the 6 year old yeast under the same conditions. (By the way, I adjusted the initial water temperature to 105-degrees-F)

They both rose and frothed. BUT, the older yeast didn’t rise as much.

Here’s the comparison:

Old yeast compared with new yeast

The yeast on the left obviously rose more than the longer stored yeast on the right. It’s not a huge difference, but definitely different. It could have been wore if I had not stored them well.

Tip: This Yeast Spoon is very convenient for measuring the perfect amount for making bread. It holds the same quantity as a packet of active dry yeast. 2-1/4 teaspoons.

>> view on amzn

Storage Tips:

How To Store Yeast and Shelf Life Results

Air tight container for storing yeast

Best: Store Yeast in the Refrigerator

In the fridge.

Apparently the science indicates that active dry yeast is best stored between 33 and 38-degrees-F.

Most yeasts in a package can be stored at room temperature, with the exception of fresh yeast, which should be refrigerated. For best results, use by the date on the package.

For better shelf life of ANY yeast, consider storing in the refrigerator.

Tip: For best results, do not store fresh yeast in the freezer.

Generally, sealed packages of dry yeast can last around two years, with the exception of fresh yeast that’s best used within several weeks of purchase.

Keep opened jars in the fridge for up to four months.

~ Fleischmann’s Tips

What About Storing Yeast in the Freezer?

I have had some success storing yeast in the freezer. Others too. However I have also read that yeast cell damage can occur if the freezer temperature is too cold.

Maybe we’re talking about the difference between storing yeast in a refrigerator freezer versus a subzero chest freezer.

I used to store yeast in the freezer. But I don’t do that anymore. I keep bulk quantities (vacuum-sealed) on a shelf in a cool/dry environment. All opened yeast goes in the fridge in a sealed container(s).

Storing Yeast: Keep Air-Tight and Dry

Make sure the yeast container is sealed. Air-tight in a appropriate seal-able container. NO MOISTURE!

Yeast will go bad if exposed to moisture or high humidity.

Yeast Container

Several size choices from OXO. For example, this one is 0.4 Qt, ~ 3 x 4.3 x 4.3 inches. It will hold 1 pound of yeast (my Fleischmann’s 1-pound packs measure 4 x 4 x 2). Push the button to engage the airtight seal. The button doubles as a handle for the lid.

OXO Good Grips POP Container – Airtight Food Storage – 0.4 Qt
(view on amzn)

image shown storing baking powder:

Yeast Shelf Life?

Some say that yeast will keep well in the refrigerator for 6 months after opening. But I know it’s much longer than that! What happens over time is evidently a slightly lesser rise. Eventually you may notice.

My experience: Unopened sealed active dry yeast will last at least for several years under good storage conditions.

We have saved a number of the (4-ounce) Fleischmann’s jars and use them to dump in the yeast from a 1-pound packet when we open up a new one from storage. One pound will fill four jars, which we then keep in the fridge.

What are your experiences or recommendations how-to store yeast long term?

What is your yeast brand of preference?

I’ve been using Fleischmann’s for many years.
SAF yeast has been good too.

16 Ounce (1 lb)

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  1. My favorite is saf, and Red Star a close second…haven’t used Fleischmann’s in a very long time. Last time I made bread, used saf that was three years old (stored in the fridge) and it did just fine!

    1. WOW, saf yeast sure is popular on amzn. I had used it a long time ago, and it was fine. I’ll bet they’re all about the same.

      Many of them seem to have good reviews and ratings, in including Red Star.

      That’s one reason I asked that question – curious if others have noticed any difference with brands.

      1. I like SAF. It is in the pantry but will put in the freezer. Keep my open package in the freezer. I have a Lock Lock container that works perfectly.

      1. We used yeast that was a bit older than 6 years on the best before date. Tested it and it rose but not what like Ken showed so we added more a tried a loaf in the bread machine and got a decent but not the greatest loaf. Adjusted yeast by adding an extra 1/4 teaspoon and that seemed to work. Was Fleischmans in the standard glass jar stored un refrigerated in a cool basement pantry.

    2. I have successfully used Fleischman’s Active dried yeast 18 years beyond the due date. It was stored in a dark pantry at room temperature. Proof the yeast (as above) to see if it has any activity. then use the yeast to make a poolish, 50 gms. of flour 50cc. of water and a small (1/4) tsp. of yeast. Ferment on the counter until you see bubbles, then into the refrigerator overnight. The next morning you have the equivalent of 2 pkgs. (5 gms.) of fresh yeast ready to use.
      This is a great way to extend your yeast in this dearth caused by the Covid-19 pandemic.

    1. White Cracker;
      A word or two on Red Star Daddy.
      Holy CRAPO that stuff can be hot, I did a 170 gallon batch of Apple “Wine” last weekend, rehydrated the Yeast (one full pound) first so-as not to give it ‘sugar shock’ added it when ready and sealed the Fermenter up, within 2 hours the Air Gap was bubbling like a Steam Locomotive. The next day it was a full-on stream of CO2.
      At that rate it should be ready for refinement within a cpl of weeks, Can anyone say Sparkling Apple Cider?

        1. Ken;
          About 3 weeks, I know a LOT of drunks… HAHAHAH
          Tis a 5 barrel Conical Fermenter, works GREAT for Wine
          100 Pounds of Apples ground up
          175 Pounds of Sugar dissolved in water
          1 Pound of Red Star Daddy Yeast and fill the Fermenter
          Fill with Water
          Seal that puppy up with a Airlock Bubbler and wait a few weeks
          Makes a heck of a Gift for Christmas and Thanks Given dinners.
          Nothing funnier that watching non drinkers guzzle down a few glasses of Hard Cider (after being warned of course).

      1. Yup some good stuff RSD leaves a good flavor when refining your apple “wine”. Tolerance to higher alcohol yields is defiantly a priority when making high test wine.

        1. I use one individual packet of fleishmens active dry yeast in a 3 gallon batch of blackberry wine. Works great! My low tech recipe teals a high quality blackberry port in about 3-5 years.

      2. WOW that a lot of yeast. I inoculate 5000 gallon batch cooked corn with one pound of Lalvin and I have a 5 day fermentation before distillation.

  2. We use Fleischmann’s normally, and Red Star second. Haven’t noticed much difference. Now that the subject is brought up, it made me feel like making bread. I have an old bread recipe book I found in an antique mall. It has all the old bread recipes and hot roll recipes in it from way back when. Some are pretty darn good.

    1. BigBadCat
      What is the title of your bread book? Year of publication and who were the authors of the book?

      I have one that I was going to put in the yard sale or give away but know rethinking this for future needs.
      If I keep this up, it will take several long haul trailers to hold all that we keep…rowl

  3. Maybe just adjust the rise time to compensate for the yeast being older.

    We keep our yeast in the freezer until needed, no problems yet.

  4. Agreed on the Fleishman’s Yeast, good stuff, I have used Red Star and Saf, but keep coming back to Fleishman’s for the price at the local Sam’s Club.

    Additionally I keep several different Beer Yeasts on hand for different Brews, from Stouts to Lagers and everything between, even Champaign Yeast for those High Octane Beers (24 percent Beer). One more I do store, like White Cracker, I have several pounds of Red Star Daddy for Fermentation of Extreme Octane “beverages”.

    I keep the Bread Yeast in the freezer, the rest in a “Garage” Kegerator kept at 34 degrees, I like COLD beer.

    I know we have had articles on Sour Dough Breads, the ‘Starter’ is easy and seems to always produce a good quality bread.

    Tis interesting that we often talk of keeping food-stuffs in a cold environment for long-er term, seems this is a good example of that.

    BUT 6 year old Yeast that’s still good, Not Bad, kinda shows ya the BS we get from Producers about “Best By” dates huh?????

  5. Make your own, keep a starter. Put the starter in the freezer and pull it out when necessary. A lot easier on flour than the traditional method and no waste.

    1. You can also thinly spread some starter (about 2-3 tbsp)on parchment or waxed paper and let it dry overnight. In the morning, it will crumble into flakes. The flakes will keep at room temperature for about a year. To make fresh starter, combine the flakes with equal parts water and flour.

  6. Do not keep your yeast long-term in a zero or sub-zero freezer. It will slowly kill the yeast. The freezer part of a fridge freezer combo is ideal. It will last almost indefinitely. I love making our bread, and for a long time I have used Jim Leahy’s recipe using only 1/4 teaspoon of yeast per batch. His book is called “My Bread” and it is wonderful. I also keep starter going and occasionally toss in some starter as well, sort of like an Italian “biga.” Mix the dough up the night before, bake in the morning. Such flavor! Delicious! You can use fresh ground wheat, just adjust the water for it. I like a combo of fresh ground wheat and bread flour. I also bake it as a pot bread, Italian loaf, French baguettes, or rolls. Love it! And my yeast lasts a really long, long long time using only 1/4 teaspoon per batch.

  7. I have been storing all yeast in our freezer (except a quart jar for current use). I learned about doing that here, in a previous article several years ago.

  8. I store my yeast in the freezer. When I open a package, half goes in a pint jar for the frig and more immediate use and the other half goes into a pint jar and back in the freezer. I have used yeast over 4 years old with no problem. But I did notice one that stayed in the frig longer than normal was not as active, which is why I now place that second jar back into the freezer after opening. I have increased the amount needed when I don’t get a good rise.

    I have used all of the different yeasts named. The Fleishmans I believe I got from Sams club in the double packs. Some of the SAF I got from my son’s friend that worked for SAF, and they have a couple different types of yeast also. The other brand I purchased from the Amish store. I prefer putting my yeast in warm water and starting my bread with the soaking methods, but I always try new recipes that do not include this process.

    It is probably time to review my yeast supply and perhaps replenish with newer since you never know what is coming down the line. Thanks for the article Ken!

  9. I use the Fleishmann’s Traditional yeast. Expiration date of this jar is September 2020, but this isn’t my first jar. I store it in the fridge. It NEVER doubles in size or froths like your pictures. I get a slight foaming on the surface. That’s it. Am I doing something wrong? Should I wait longer than ten minutes?

  10. I place yeast in a “Ball” mason jar and that goes in the fridge. Did I mention I vacuum seal the jar before it goes in the fridge? That takes out all of the oxygen and the moisture.

    1. I put my yeast in a mason jar and didn’t vacuum seal the jar. Now my yeast is not proofing. :( On my third attempt – did I just screw up a lb of dry yeast? I’m so new at this – just started bread making since covid.

      1. Li;
        I would need to ask how old the Yeast is, What Temp was it stored at, Did you re-hydrate the Yeast before using it.
        Normally storing Yeast in a Mason Jar will not kill the Yeast, even if not vac-sealed.
        I do not keep mine in the Fridge and it will last literally for years, sometimes when over two years old I increase the amount some.

  11. When I bloom my yeast in water before adding it to a recipe, I also add a dash of sugar to it. Make sure the water is somewhere around 105-110 deg F, and stir the sugar and yeast around a bit. Then let sit for a bit. The sugar feeds the yeast and gets it bubbling. That seems to work really well. And just a little dash of sugar isn’t enough to be tasted in any recipe, even savory ones.

  12. Thank you for the information, I will test my yeast to see if it still work like you said, if not I will trash it. It has always been kept in the spare fridge freezer.

  13. J.B. Don’t just throw the yeast out; if you have a septic tank at your place, put it in a 5 gal. Bucket with a pound of brown sugar than fill the bucket with water, let sit for 2 days then, pour equal amounts down all of your drains. Your septic tank will love you

  14. blackjack22
    That is good news, did not know about the brown sugar. We would just dump it down the drain with warm water for the septic.

    1. AC, If you put the yeast in with the brown sugar, the yeast will “activate” and get all frothy. If you let the mixture sit for a couple of days then, the yeast will become more “active: and when you pour it down your drains you will get more/faster activity in your septic tank, which is a good thing for your tank.

  15. I recently used some fleishmans yeast that was in the freezer for like….3 years. It had been opened. No rise !! a big flat scone on the bottom of the bread pan. Will try fridge…….

    1. Faith Gillis Pietruszka:
      A little late on the responce, hopefully you will get this.
      Yes I store Flesfman’s yeast in a 1 pint mason jar, holds right at one pound of yeast.
      I do not use a moisture absorber.
      Current yeast has been in fridge for many many months without degradation at all.

  16. Kind of late to the party… I bought a 2 pound vacuum sealed block of Red Star active dry yeast from Costco. I figured that it would be okay to store with my other preps in the basement, just on the shelf (since it’s already vacuum sealed and BB date is 2 years out).

    Do you think that I should put the vacuum sealed block into a vacuum seal bag and seal it for extra protection, and maybe it would last even longer? We are having a bit of a humidity problem in the fridge at the moment, otherwise I’d put the block in there as is (and I don’t know if you heard, but now is not the time to find a fridge). TIA for any help on this.

    1. An extra layer of vacuum seal will only help if the other seal is somehow defective. I store mine in the freezer. The humidity in the fridge shouldn’t be an issue as long as the original seal is intact.

    2. Newish:
      No. I’m using Fleishman yeast thats a good 5-6 years old stored under the house (crawl space).
      Zero problems, would suggest using about 1/4more yeast when you do use it.

    3. Newish,
      Glad you made it to the party… On Refrig.. Check your seals on the doors, the gaskets, make sure they are clean and seated well… sometimes conditioning them will do it.. you may be getting air intrusion somewhere..causing refrig to run more than normal and not pull moisture out.. clean the coils and check and possibly blow out(compressed can air?) the drain lines to the pan underneath it…

  17. An update on the Yeast Storage.
    I have moved the long-term storage to the Crawlspace along with the other stuff. Freeze space is to valuable for Yeast.
    Opened packages (1#ers) get dumped into a pint jar and stuck in the refrigerator.
    I have had zero problems with 5-7 year old yeast, just add a little bit more, 1/4 as much.
    I still prefer Fleishman Yeast. Old School I guess.

    1. NRP,
      Gee, with all the “farming in the woods” you seem to do down there, I figured your yeast supply would be turned over more often.

  18. I do store yeast in the freezer and I’ve never had problems. However, when I don’t use the breadmaker I’m making no-knead bread which just goes in the oven when it’s ready, however long that might be. The yeast is still good, it’s just slower to develop when it’s older.

  19. Storing dry yeast in the freezer is an excellent method. It’s dry; so, the cells won’t burst when frozen which happens when ice crystals form in fresh or liquid yeast. I freeze liquid brewer’s yeast in the freezer – real freezer. Let the yeast settle and pour off the water replacing with glycerin. It works fine.

  20. For those unaware, Lesaffre is the corporation that is SAF yeast and Red Star yeast. They also offer other products commercial bakers would be interested in. All of the SAF yeasts are color coded for commercial use, red being an all-around bread/pizza yeast. Blue and gold are for high sugar doughs (up to 30% sugar). I forget what green and purple are for. I believe all of the SAF yeasts are instant yeasts and Red Star is sold as active yeast or cake (fresh) yeast. Both product lines target commercial bakeries … yeast is available in 50-lb bags. I think Lesaffre brands one SAF instant yeast as Red Star for the home market. One of those lines now offers a yeast for freezing dough … make bread dough then freeze it, thaw at room temp and bake with no loss of flavor or leavening. SAF red and blue are popular for home bakers. When it is available, Costco Business Center sells 1-ln bags of SAF red for around $2.70.

    Regardless of brand, instant yeast does well in the freezer, last indefinitely.

    Not so with active yeast, best kept in the fridge.

    You can extend life for a couple years in the freezer. Cake yeast must be kept in the fridge and has a 42-day usable life.

  21. Thank you for sharing this info! I have been looking for good-sized container to store m 1lb vacuum packed yeast in.
    The 0.2qt OXO POP container you recommended seems so tiny! Does it fit an entire 1lb pack of yeast?
    Thank you!

    1. @ SLS,
      Thanks for the question. The 0.2 Qt would work for dumping in the small containers of yeast (such as the typical 4 oz jars).

      I’ve just changed the link above to reflect a more common use-scenario (for up to 1 pound of yeast storage). The 0.4 Qt size which measures about 3 x 4.3 x 4.3. My 1-pound Fleischman’s packs measure 4x4x2.

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