If you are looking for a quick and fool-proof method to create a starter that has a high concentration of lactic acid, check out Rus's CLAS procedures on YouTube [1] and Blogger [2]. Mind you though, the formula uses commercial yeast ("CY") to boost leavening power because CLAS is yeast-free.  If you're a hard-core purist who does not use CY,  this method is not for you.

Thanks to Rus for sharing this opening technology with us!

 100% Rye

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pH @ 1500 hr

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@ 2400 hr

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pH @ 2400 hr, it's ready for bread making 

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pH after refreshment; acidity continues to increase

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