Been a quiet lurker here for a few years and I have had many questions about cheese making that I easily find answers for by searching this site, up until now. So much knowledge here it`s incredible! So, I`ve been working hard on keeping pH targets exact with my pH meter to fix some overacidification problems and amongst my attempted remedies is to be more precise with the amount of starter culture I use. Instead of using tiny measuring spoons I have bought a micro scale (precision to .1 of a gram). Problem is I cannot find any recipes that use weight for measuring cultures. Is there a guide anywhere that explains how much 1/16th , 1/12th etc. of a teaspoon is in weight? I use DVI starters exclusively and wish to continue doing so. My make size is 14 -16 liters of milk. Thanks very much for any help you can offer.
Bear, it's a bit cumbersome, but you'd have to see how many DCUs per weight there are in your particular lot, of your bought culture. E.g., say it says 50 DCU, 25 g pouch. You now know you've 2 dcu per gram. Each culture, even each lot of each culture, is different - one pouch of culture x might say 50 dcu and 25 grams, another of the same culture but a different lot might say 50 DCU and 22.3 grams. It's to do with the manufacturer's voodoo on "acidifying strength" of each lot number. More complicated, but it's enough to know the pouch DCU and weight (some don't give you that - just the DCU and/or dose; you'd have to find the net weight of the pouch, to figure the DCU per gram....more of a pain).
There's a conversion of mother cultures in bulk, danisco and CHR Hansen somewhere on this site - sorry, I've lost track. But as a for instance, say you would like to do a 1% bulk equivalent of starter (bulk equivalent meaning, if you were doing this with bulk culture, you'd be putting it in at 1% v/v). Let's say you were doing a 4 gallon batch, 15.1 liters. 1% by volume would then be 151 milliters. The equivalent, given in this chart, of Danisco DCU (at 1% bulk equivalent) would be .98 DCU. So, knowing your culture comes in at 2 DCU per gram, you would use .98/2 or .49 grams culture.
You might want to double check me on this - I am prone to spacing if I don't slow down, but I believe that's correct. Let me know if you can't find the chart I'm talking about, I believe Sailor Con Queso kindly provided it on one of his threads (look up "mother and DVI culture calculation"), and Sailor or Linuxboy are the go-to guys for this stuff. I think it checks out, though, and in the event they didn't get back here soon, wanted you to have something. Good luck.