I read recently, unfortunately I did not record the web address, of a technique for progressive building of a starter/levain whilst changing the hydration progressively, if required. The idea is that you don't shock your beasties by a 'sudden' change in hydration, the growth of the population is controlled and invigorated by the regular feedings and there is not an excessive volume to be populated at any one time or that cannot be used by the population.
The technique was to start with a small amout of your culture and to increase the mass in three stages (0,8 and 16 hours) so that after 24hrs you had the required mass and hydration of starter/levain that would be alive and kicking the proverbial six pointers.
The link that follows points to a spreadsheet that you can down-load that does the calculations for this method for you.
Data entry is in the top half of the area and includes your target hydration, target mass, a buffer mass (to allow for errors/losses) and the hydration of your starting culture. Using TAB between entries jumps to the next data entry cell.
The results appear in the bottom half in the grey cells. The intermediate hydration figures are for information only.
I hope this proves useful. Any ideas for other 'calculators' or improvements to this one, feel free to contribute.
Farinam, Thank you so much for sharing this spreadsheet. I've been struggling along with a 166% hydration starter. I've found recipes calling for a lower percentage and thought I was unable to use that recipe because I didn't have the right hydration. Now, I can use them, thanks to your spreadsheet calculator help. Thanks again for your generiousity. Happy Baking! Mary
I've tried a couple of combinations and they all seem to work. I say 'seem' only because I have not verified all of your calculations. Your calculations are more sophisticated than those I used on my spreadsheet and I am not sure that I would be able to work my way through them with ease.
On my spreadsheet the amount of levain to start with is kinda touch and go. I did not know how to calculate that amount. With your spreadsheet, I think that that problem is solved. I shall work a bit with your spreadsheet for a while and see how that goes. I believe it will be a big help.
On a more general note, I am thinking that the usefulness of those spreadsheets [yours, mine, and anybody else's] could be enhanced if some of the cells would include comments that explained to an interested user how a particular result has been obtained. If I can find some time, I might do just that on my spreadsheet. Do you think that would be a good idea or would it be rather overkill?
I don't see any problem with documentation. I guess I was relying on people having read my blog to know what it does. When I get a moment, I will add some commentary and upload the new version.