Creating Fruit Yeast Water Starter

Creating yeast water couldn't be easier, simply combine fruit and water, and you'll be ready to bake naturally leavened bread in less than a week. Here, I'll show you how you can use yeast water to create a sourdough starter that's ready in 3 or 4 days, instead of 2 weeks. 

If you've ever made a sourdough starter, you already know that yeast is all around us. All we have to do to harness its power is to harvest it. When you create yeast water you are harvesting the yeast that naturally occurs in fruit and vegetable skins or pulp. 

Although the process couldn't be simpler, there are a few things you should note before making your yeast water starter:

Avoid using mango, pineapple, kiwi and papaya. 

You can use almost any edible, non-toxic fruit or vegetable to make yeast water, except for these fruits which contain a protease enzyme called actinidain. This enzyme destroys protein and inhibits gluten development. 

There are some bakers who have succeeded in using these fruits, but they must be cooked or specially treated first. As a first timer, I would avoid these altogether. You can do a deep-dive and research ways to use these fruits yourself if you wish. 

Temperature matters

Yeast water starters love warmer temperatures, the ideal range for yeast water fermentation is between 77 F to 80 F / 25 C to 27 C. A yeast water culture can incredibly temperamental and their activity is greatly dependent on environmental variables. Hot temperatures can make your yeasts explode with activity, while cold temps can make it stall. 

When my yeast water bakes have failed in the past, it was because my kitchen was a tad bit too cold. I've been most successful with yeast water in the summertime. 

Yeast water activity can vary wildly

Wild yeast are fickle beasts, in comparison to sourdough, yeast water can be quite unpredictable. I've had yeast waters that literally explode like a can of soda that has been shaken, and some that just fizz a little, know that explosiveness is not a prerequisite for a viable yeast water. 

I've found that my yeast water is most active at day 3 or 4, during this time my dough can rise almost as fast as if I used commercial yeast. But using it past this point, at day 6 for example, resulted in more sluggish activity, with similar or slower rise times than sourdough starter. This is why you need to watch for signs of readiness in your dough, instead of the clock. 

As one baker once told me, when baking with wild yeast, hide your clock and pay attention only to the dough. 

You can use yeast water directly in your bake

Yeast water can be added directly to your dough without creating a starter. Your yeast water is always ready for use, you don't need to feed it like a sourdough starter to use it in a bake. 

But as I mentioned above, activity is really unpredictable and this is why I'd advise creating a levain with flour and yeast water anyway. This will let you "proof" your yeast, observing the activity of your levain can also allow you to gauge rise times of your bread. 

Most yeast waters will not affect the flavor of your bread 

The flavor of bread made with yeast water is more neutral than bread made with sourdough starter. Because the tang of sourdough develops overtime, the bread you make using your yeast water won't have the same flavor as breads made with starter. As your starter ages it may develop this tang down the line, but it won't have this flavor immediately. For this reason, many bakers prefer using yeast water to make sweet enriched breads, and pastries. 

Most of the time, the flavor of the fruit you use for your yeast water won't transfer to your finished bake. There are some fruits or vegetables that affect the flavor of bread, however, I haven't baked anything where this has occurred. I'll be sure to announce it on my Instagram if or when I do! 

Test for pH level

It's important to ensure your yeast water is safe to consume by testing its pH level. This can be done easily using pH test strips. Your yeast water may appear active, but it may not be acidic enough, therefore unsafe for consumption. Safety is paramount, your yeast water should register at a pH of 4 or lower before you can use it. 

Maintaining your active yeast water

There are a few options for maintaining your yeast water starter

Convert it to a sourdough starter. Once you've created a starter using flour and yeast water, you can now maintain that as you would a sourdough starter. There are many articles online about sourdough starter maintenance, so I won't recount the steps here. Know that feeding your starter with plain water at this point is absolutely fine, and you won't need to keep using yeast water to maintain your sourdough starter. 

Refresh it with fruit or sweetener. After your yeast water is fully active, you can strain the fruit out of it, keep the liquid and store it in the refrigerator indefinitely. Once you'd like to use your yeast water again you can top it off with some fruit or even sugar and keep it at room temperature before use to increase activity. 

Process

Things You'll Need

• Container (1 liter bottle or 32 oz jar)
• Fruit (any edible and non-toxic fruit or vegetable, I used grapes***)
• Water
• pH test strips 
• Flour

***You can other kinds of fruit, but I've been most successful with grapes, so I recommend using them for your first time. 

Instructions

Create Your Yeast Water

Day 1:

Split a handful of grapes (10 to 15) in half and place them in your container and cover them with 4 to 5 inches / 10 to 12 cm of water. 

On the first day, your water will be clear and all of the grapes should lie in the bottom of your container. 

Set aside and allow to ferment.  

Day 2: 

Loosen the lid of your container to release any CO2 build up. Place the lid back on tightly. 

Shake your yeast water vigorously. This prevents mold from growing on your yeast water. 

Repeat this process once or twice.

Day ¾:

Release any gas buildup and shake your yeast water vigorously, 2 times throughout the day.

At this point the water in your yeast water may have changed colors and all the fruit should be  floating. 

Test the pH level, if it registers at 4 or lower, your yeast water is ready to use. If not continue to release gas and shake until it is reaches the optimal pH level. 

Create Your Starter

In a separate container or bowl, combine 30 grams of yeast water with 30 grams of flour. 

After 3 to 4 hours, if your starter doubles and appears bubbly it is ready to use and will be strong enough to bake bread! 

Et Voila!

Creating a sourdough starter using yeast water is such an easy and uncomplicated process. If you've had trouble making a starter the conventional way or if you don't particularly like the tang of sourdough, I recommend trying this method out. I love how creating a yeast water allows me to use fruit that I would otherwise toss in the bin. 

Did I cover everything you wanted to know about fruit yeast waters? Let me know in the comments if you have questions I didn't answer in this post!