I tried the oven method recently and ended up with soupy yogurt. I'm guessing this is because I used a cheap store-brand yogurt for the culture or it didn't stay warm enough overnight or some combination of the two. I plan to buy some Dannon soon to see if that makes a difference. I had pre-warmed my gas oven prior to putting the mixture in it. I also left the light on hoping that would help keep it warmer. I'll let you all know if switching to Dannon makes a difference when I get a chance to do that.
You can "Greekify" regular yogurt pretty easily. Just line a sieve with a couple of paper towels, dump in your yogurt, and hang the sieve over a bowl to drain. Leave it in the fridge overnight, and in the morning, you have nice, thick yogurt.
I don't know if this will help with any of the "soupy" yogurts discussed in this thread, but it works great on Stonyfield yogurt, which is pretty thin.
I'm interested in the idea of using a crockpot. That seems like a good way to get a constant temperature. Would it be too hot? How long and what setting (mine has low and high).
I think the low setting is still way to hot for yogurt. My slow cooker has a keep warm setting which I have checked and it keeps the temperature at about 140 ºF which I think is still to warm. My recollection is you want about 120 and anything over about 135 will just kill the bugs.
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Jeff Hansen
Department of Chemistry and Biochemistry
DePauw University
602 S. College Ave.
Greencastle, IN 46135
jhansen@depauw.edu
I don't know if they are all this way, but even on low, my two crock pots
would be too hot. They are designed to cook either slow (250 W)or slower
(160 W), but cook nonetheless. Perhaps if you found one at a thrift store
and dedicated it to only to yogurt, you could modify it to operate at a
lower temperature.
It's a resistance device, so a suitable voltage divider or solid state
device should work. A lab rheostate might do it, or at these power levels
maybe even a light dimmer switch with a 250 or 300 W capacity. Ramp it down
with water in it and measure the temp in the morning to see if it's 120F or
less.
Hello yogurt enthusiasts,
Lactobacillus feels best between 34-46 degrees C.
In Bulgaria we use an old blanket or sweater to place the container in and cover it as a bundle well, cover more if needed and keep it away from a draught. No incubators or other temperature maintaing equipment necessary. You can start at 46 C, it will cool off in the process. Select a wrap that can hold the temperature for at least 6 hours, although you can have a faster process if using more starter than the ca. 5% I use.
This is how my grandmother did it, how my mother does it when she gets large amounts of fresh farm milk and it always turns well. I had to learn when I first came to the US. As fermentation is a complex process, the product might vary from batch to batch so don' t get discouraged by variation in sourness or texture. It might be runnier than commercial products but the taste will be much fresher.
I use glas containers that are easier to clean well, can be larger as we are big users and cool fast in the fridge. Cooling the yogurt before tasting or putting with jam in containers is important to get a thicker texture (but there are many other factors like the starter that can influence texture).
I have tried various yogurt makers but revert to the sweater method as 1 L is too little for us and noticed temeprature variations at the bottom of the appliance. Some ovens have functions for yoghurt (Kitchen aid ovens seem to have one) I have never tried one.
A coffee filter is easier to scrape off than paper towel if thickening the yoghurt.
Venetka Agayn
Thanks Venetka for reminding me about the sweater method. This is what we did back in Poland! I am going to try it as soon as I am back from the national meeting. We used to drink our yogurts so we did not care so much about thicker consistency!
Marta
Marta Gmurczyk, Ph.D.
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