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Mike's (more or less) Weekly Baking Tips Logo2019-06-11 - The Five Percent Solution

From Mike's (More or Less) Weekly Baking Tips

My dad has been in a physical rehabilitation center to try to get him in better shape. And that made me think of other rehabilitations.... of course, I mean rehabilitating an ailing starter. My view is that if you take care of your starter, that is to say, feed it regularly, this discussion isn't necessary. But as the saying goes, "stuff happens". If you are looking for a more in-depth discussion, look at our "reviving starters" page.  (As an aside, dad did get better.  Aging is not for sissies!)

We'll present two different ways to revive a sluggish starter, one this week, and one next week. This week, we'll talk about the 5% solution. This is how Blair Marvin of Elmore Mountain Bread handled starter in class. I like this approach because it is very simple and it works. Like me, Blair feeds her starters twice a day, and uses what some call a 2:1:1 feeding regimen. That is, she feeds the starter enough to double it in size with each feeding. Or, to 100 grams of starter, she'd add 50 grams of water and 50 grams of flour. This keeps your starter going, and it should double in size between feedings.  Some people point out that this leads to a starter that is excessively acidic.  While that wasn't a problem when we lived in the mountains of Colorado, it does seem to be a problem at sea level for what some call, "reasons unknown".  In any case, if you want a real fire breathing rip-snorting container bursting starter, do what Blair does.

Before we go any further, if you click on the images of spreadsheets, you'll see a larger version of them.  One you can read.

Her last feeding before she uses the starter is at 2:19:19, or put another way, this is a massive feeding where the starter being fed up is 5% of the final amount of starter. To make 1,000 grams of starter, she'd use 50 grams of active starter, 475 grams of water, and 475 grams of flour. If your starter was active, this will make it explode (figuratively, anyway).

When I heard about this, I was sure that thus extreme a feeding would knock the sour-taste producing bacteria WAY into the background, producing a very bland bread. However, that did not happen. The bread was very nice.

This technique allows you to maintain a smaller amount of starter than doubling it twice a day would lead to. Again, my own preference is to feed a refrigerated starter for three days before using it. If you'd like to download a copy of the starter calculation spreadsheet, just download this archive from our web site.

The rest of this post will be about using the spreadsheet. The file in the archive you want is startercalc5.xls This file will work with Microsoft Excel, OpenOffice Calc and LibreOffice Calc.

Unless you want to modify the spreadsheet, everything you need is on the first sheet of the spreadsheet.

Column B has the labels thatA look at the control are of the spreadsheet describe the contents of column A. B3 says "Method" and A3 has a dropdown menu which allows you to choose between nine different feeding protocols for your starter.

To the right, around area C1 - H4 is an explanation of the feeding regimen you have chosen.

Cell A4 is where you enter the number of grams of starter you need.

Cell A5 is where you can enter the date when you need the starter. In this example, I want to use the starter on June 16th, 2019.

Cell A6 is where you can enter the time of day you want to use your starter. In this example, I want to start mixing my doughs at 7:00 AM.

Cell A7 allows you to enter the percentage of Calcium Sulfate you want to add to your starter. Calcium sulfate, also known as Gypsum, is used to harden soft water and was part of an effort on my part to investigate the impact of harder waters on dough development. My suggestion is don't use it. I'll probably remove this field in the next version of the spreadsheet.

To the left, you can see the dropdown menu showing the none feeding protocols this spreadsheet supports.
A look at the method dropdownAs you select different protocols, the descriptive text to the right will change.

The screen capture below shows the feeding schedule for the amount of starter I have selected, 1,500 grams. It shows 5 feedings, the number of feedings shown by the spreadsheet will depend on the amount of starter you are feeding, and the method you are using. If the screen capture is too small to comfortably read on your computer, you can click on the image to see a larger version of the image.

Sorry about the absurd fractions, feel free to round the numbers. (That will be a project for the next version.)The feeding schedule (click on the picture for a larger view)

As a "reality check" the spreadsheet shows the desired and actual amount of starter the feeding should produce, any error in the amount due to rounding, and the starter hydration.

Of course, there are real world influences on the amount of starter you actually create. The amount that gets stuck to your spoon, carried out of your mixing bowl and lost. The starter gives off carbon dioxide as it ferments. And there is a certain amount of evaporation. I usually make about 10% more starter than I actually need so I'll be sure I have enough, and to be sure I have some left over to build up to the next bake.

If you have questions, please get in touch with me! Until next time, may your dough always rise, no matter how you fed your starter!

2 thoughts on “2019-06-11 – The Five Percent Solution”

  1. Thomas Cappiello

    I’ve had my starter for about 20 years and I don’t know nutin. Lol. It just does what it does, of course we humans can have some influence. I think I’ve read just about everything written by microbiologist Debra Wink on The Fresh Loaf and have come away more confused, and paranoid than ever. Based on her knowledge and writings, I don’t fully understand why a 5% feed favors a yeast growth (and thus lower acidity) because it will take longer to develop, and the longer it takes the bacteria growth will overtake the yeast, of course temperature is a huge factor too. Anyway, I’d like to see some data and further investigating on this. I do know my starter does get acidic (or proteolytic?, or excessive thiols from respired yeast?) over time and ramping up by by starting out at a low % does help. . Karl De Smedt at the Sourdough Library provides instructions on how to “wash” a starter to lower acidity. This actually makes some sense to me, but I have not actually tried it.

    1. Hi Thomas,

      It is certainly possible to over think things. I’ve read a number of technical papers on sourdough and am left with the reaction of, “Huh? What does that mean to me as a practical baker?”

      With regards to the 5% solution, how do we know that the extreme feeding favors the yeast? If we were microbiologists we could take samples throughout the fermentation and see what happens with regards to bacteria and yeast. If we are practical bakers, we could look at the starter, see it was becoming very active, and then taste it and see it was less acidic, and make a logical conclusion.

      That observation, whether through microbiology or a practical baker lens, would tell us what is happening. The why of it is another matter entirely. I suspect the microbiologists would have to work hard to answer it. However, for the practical baker the question remains, “how’s the bread turning out today?”

      While learning is, in itself, it’s own reward, if you like the bread you’re making, there really isn’t any reason to change things.

      Best wishes,

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