How to Tell When Yeast is Still Viable
I never really needed to know how to tell when yeast is still viable, because I always manage to use it up before it gets a chance to go bad. The other day, however, I set out to make my world famous—perhaps only in my mind—pizza dough, when I took out a packet of yeast from the fridge only to find it had expired by a full year and a quarter! How could this be??? Well, I’ll tell you.
Tommy—bless his heart—didn’t bother to look at the date on the package when I sent him to the store to get some. He bought it assuming it was fresh. Silly assumption indeed! Here’s a lesson for you home bakers; always check the expiration date on yeast packages.
Now, any rational creature would assume this long expired yeast is no longer viable, but I never said I was rational. I am, however, frugal as can be, and I just didn’t see tossing the yeast away without testing it first. It wasn’t just one packet of yeast we were talking about with the long expired date. It was several 3-packs which adds up to a lot of dough!
Expired yeast? What a waste!
I went ahead and made the pizza dough as usual, hoping for the best. Well, blimey, don’t you know, it was fine and dandy. The dough was not as high rising as usual, but still made a nice soft dough and great pizza. So, having just proved to myself that the long expired yeast was still viable I made extra batches of pizza dough to use it up quick—lest it get non-viable within the next week or so. One never can tell and it’s best to be safe than sorry. In future I’m keeping my yeast in the freezer!
Raising some dough
Of course, if the dough had not risen properly I could have used it for making flat bread, bread sticks or even crackers. I did mention once or perhaps a hundred times that I am ever-so-slightly frugal, right?
Yummy fresh bread
Having said that, there is an easy way of testing the yeast for viability without going through the making of dough and possibly wasting flour, if you don’t wish to. Here’s how to do it.
How to tell when yeast is still viable
- Pour a half cup of very warm water (110-115℉) into a small bowl.
- Add 1 teaspoon sugar and one packet (2 teaspoons) of yeast to the water and stir.
- You should see three layers form; the bottom layer will have the sugar and yeast. The middle layer will be cloudy water and the top layer is a yeasty film.
- Wait ten minutes.
- If it foams and bubbles the yeast is still viable. The layers should be now milky looking water with foam on top.
You can now use this without fear of a dud. If the yeast mixture just lays there looking dead, you can still use it to make a flat bread, bread sticks or crackers.
Fresh is best with almost everything even yeast, but it is good to know that there is an easy way to tell when your yeast is still viable, so you don’t toss it away needlessly.
Photo credit: Bread
Glory Lennon spends loads of time in the kitchen, cooking, baking and eating, too. You’ll find a few of her favorite recipes over at Glory’s Garden in the kitchen.