We use WLP002 which is the most flocculent yeast strain I've personally ever seen.
We're experiencing a problem with re-suspending it before pitching. Regardless of how much we shake the pitch, once it's added to the top of the FV, it sinks straight down to the bottom and sits in the cone where it has no contact with the wort. It requires rousing multiple times over a couple of days before it gets going.
We've noticed that adding about 1.5% phosphoric acid v/v to the yeast un-flocculates it and we use this method to suspend cells for counting under a microscope. However the amount of acid it takes to do the job drops the PH way below the 2.0-2.2 suggested for yeast washing and my concern is that if we use this method on our pitches, it will irreversibly damage the yeast and affect the beer we're trying to make.
I understand that EDTA does a similar job by sequestering the calcium ions necessary for flocculation to occur but I don't want to satay adding crazy stuff to our beer.
We approached White Labs for advice but their response was unfortunately extremely technically unsophisticated (rouse yeast more, use different strain).
Does anyone have any suggestions? Is the phosphoric acid un-flocculating the yeast because of the low PH or because its somehow interacting with calcium ions? Or are those two things essentially the same?
It'd be good to get some thoughts from someone with a biochemistry background.
We're experiencing a problem with re-suspending it before pitching. Regardless of how much we shake the pitch, once it's added to the top of the FV, it sinks straight down to the bottom and sits in the cone where it has no contact with the wort. It requires rousing multiple times over a couple of days before it gets going.
We've noticed that adding about 1.5% phosphoric acid v/v to the yeast un-flocculates it and we use this method to suspend cells for counting under a microscope. However the amount of acid it takes to do the job drops the PH way below the 2.0-2.2 suggested for yeast washing and my concern is that if we use this method on our pitches, it will irreversibly damage the yeast and affect the beer we're trying to make.
I understand that EDTA does a similar job by sequestering the calcium ions necessary for flocculation to occur but I don't want to satay adding crazy stuff to our beer.
We approached White Labs for advice but their response was unfortunately extremely technically unsophisticated (rouse yeast more, use different strain).
Does anyone have any suggestions? Is the phosphoric acid un-flocculating the yeast because of the low PH or because its somehow interacting with calcium ions? Or are those two things essentially the same?
It'd be good to get some thoughts from someone with a biochemistry background.
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