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4 jars experiment, inoculation

#sourdough #experiment

In this experiment I look at “total hydration” and viscosity

“Total hydration” is the ratio of the mass of water to the mass of flour, including the flour and water in the starter. Typically in my recipes I don’t include the water or flour from the starter in my hydration calc since the liquid may also include acid and alcohol, and the flour is fermented. However for this experiment I wanted to test an apples to apples comparison of viscosity so I did the math to make all the jars have the same “total hydration” of 74%.

Viscosity, as in how thick the starter is after stirring. The theory is that more water means less friction (lower viscosity) which lowers the internal stresses in the starter (or dough) and allows the fermentation to happen quicker. Less water = more friction, higher viscosity, and slower peak. In this experiment I question whether at the same “total hydration” if different inoculation starters will have different viscosities.

What I found was that the higher inoculation jars on the left were less viscous (easier to stir) than the lower inoculation jars on the right telling me there’s much more to just adding in the “flour” and “water” from the starter into the total hydration calculation. If anything, maybe just add the water, and not the flour, more experiments to come on viscosity!

The strong peak of the 100% inoculation jar makes me question if acid carryover is really a thing we need to worry about in terms of a starter’s rising power. I think the thing that stands out the most is the near identical peak of 100%, 50%, and 25% inoculation jars. This suggests that acid carryover has more of an impact on starter mechanical strength (less viscous) more than actual rising power.

Next experiment: Rerun at 100% hydration to more clearly understand the impact of acid carryover on mechanical strength (viscosity).

100% inoculation means a starter fed with 100% sourdough (1:1:1 as an example)
50% inoculation example would be a 1:2:2
25% would be 1:4:4
12.5% would be 1:8:8

All my feeding ratios are always starter:water:flour

These were (left to right)

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