I’ve been steadily using my new yogurt maker. It’s like a microscope: I can see things I never saw before. I started with the recommended fermentation time: 12 hours. Then I did batches at 16, 20, 24, and 28 hours. The yogurt grew steadily more sour. The increase was remarkably clear. I am unable to find this crucial info anywhere on the web — that 28 hours produces more sour yogurt than 24 hours, etc. By making my yogurt much more sour than commercial yogurt I’m getting a lot more of the crucial ingredient (bacteria).
The results are so clear, I think, because I’m starting with a hyper-pasteurized product (which can be stored at room temperature) and the yogurt maker holds the fermentation temperature very constant. Constancy of temperature means constancy of selection means greater population. (The theory behind the Shangri-La Diet says the main reason for the obesity epidemic is that we’re eating food with exactly the same flavor from one instance to the next — from one can of Coke to the next, for example.) If the temperature is 120 there is selection for bacteria that grow best at 120; if the temperature goes down to 110 many of those bacteria die and are replaced by bacteria that grow best at 110. If the temperature goes back up to 120, those bacteria die . . . and so on. More temperature variation means more diversity of bacteria but less number of bacteria. I’ll get my diversity of bacteria elsewhere — from kombucha, say.
I suspect that commercial yogurt makers are time-limited. If they fermented twice as long they could only make half as much. The average yogurt buyer has no idea that more sour = more healthy, so they couldn’t charge more.
Although the yogurt maker’s box shows the machine set to 32 hours, the actual maximum time is 24 hours. To get 28 hours I reset it during the process.
The official website of the National Yogurt Association, aboutyogurt.com, contains nothing about how to make yogurt.
The Salton Yogurt Maker might be the best yogurt maker available in America. I can’t tell if you have to preheat the milk — the worst part.
More Does more sour = more healthy? I agree with the two commenters who suggest that the number of live bacteria probably goes down after a certain point as the mixture becomes more acidic. The number of live+dead bacteria, however, probably continues to increase. My guess is that the total live+dead is maximized when the yogurt is most sour; the number of live bacteria is maximum around the tme that the acidity is most quickly increasing, somewhere in the middle. I think the digestive benefits come only from live bacteria but that the immunostimulatory benefits come from both live and dead bacteria. I find it hard to believe that the immune system can tell whether bacteria it encounters are alive or dead.
“the average yogurt buyer has no idea that more sour=more healthy…”
I don’t quite see how you know this either. There seem to be too many variables involved to really draw much of a conclusion (i.e. does it really matter how many individual bacteria you eat, is the sourness/bacteria count correlation always positive, is there more than one or two species of bacteria capable of surviving in yogurt culture with L. acidophilus, etc)
My basis for my belief that more sour = more healthy is that more sour = more bacteria (the bacteria multiply) and more bacteria = more healthy. The second conclusion I base on all the evidence for the umami hypothesis — see all those posts for the data. It’s true I can’t make a dose-response function; at some point more bacteria won’t do any more good. But I truly doubt that a single serving of weak yogurt (= commercial yogurt) is optimal.
im not so sure that more sour = more bacteria forever. more alcohol doesnt equal more yeast, for a counterexample.
We have one of these yogurt makers and found it works great with a round 2-quart (I think) plastic container of the kind sold for use with frozen juice. We don’t preheat the milk, although we use powdered milk and use warm water to reconstitute it. The recipe couldn’t be simpler — fill the container halfway with milk powder, fill up the rest with water (you need to add some water, and then whisk it around to mix it up, add 1/4 cup of the last batch of yogurt, mix it around as best you can with a whisk, and then leave it all day or over night.
If only you could readily get powdered whole milk in the U.S. (you can buy some imported from Mexico, but it’s expensive), it would be the perfect way to make yogurt.
On the sourness issue, I note the increasingly prevalence of “tart” frozen yogurt places in my college town. Perhaps it’s a sign of changing tastes (or, more cynically, perhaps it’s a way to allow people to add more sugar without noticing).
I’ve also been making my own yogurt lately, and I ferment for at least 24 hours due to my lactose intolerance. When I try to use that yogurt as a starter for the next batch, however, the results are not good. Instead, I pull some of the yogurt out after 6-12 hours and save that as a starter for the next batch. I think the problem might be that the lactic acid that makes the yogurt more sour might also kill off bacteria at some point. In any case, if my yogurt fermented for 24 hours had more bacteria than yogurt fermented for 6, wouldn’t it be at least as good as a starter?
https://ezinearticles.com/?Instructions-For-Salton-Yogurt-Maker&id=1192702
Instructions for the Salton yogurt maker. You do have to preheat the milk. It also says “allow the yogurt to incubate 6-12 hours. The longer it is heated, the more tart the taste”.
https://www.williams-sonoma.com/products/e096/index.cfm#
I got one of these yogurt makers from Williams-Sonoma for Father’s day. I preheat the milk to 180, put in some powdered milk, add some yogurt for starter, and 10 hours later I have 7 6 oz containers ready for the fridge.
My best results are with Whole Foods low fat organic yogurt for starter and organic whole milk for my milk. The best batch so far used a gradual cooling from the 180 heat cycle and a 10 hour cycle. The result was very smooth, very sour yogurt.
Previous efforts at an ice bath to quickly cool the mix and 12 hour cycle yielded yogurt that felt grittier on my tongue but not as sour.
YMMV,
Jim Breed
It should really be called the “National Association of Industrial Yogurt Manufacturers.”
The salton maker I used (which looks like the one in the link) was basically an incubator that maintained a constant temperature, so all the prep work of getting the yogurt started had to be done. I found it frustrating to only do one quart at a time, so I gave the maker away and use a large canning pan where I can have several quart jars going at the same time in a water bath.
I’ve found that having a small burner set on medium-low maintains the temperature at a constant 110 or so (at least for the depth of water bath I tend to use), and I typically let that go for 24+ hours (I prefer a more sour taste apart from whether it confers additional health benefits or not).
Having two kids and using the yogurt to make yogurt cheese (which I use in ways not unlike cream cheese), it’s pretty easy to go through a quart a day (which clearly doesn’t work so well one quart at a time).
I make yoghurt myself a couple of times last months. Did not use a yoghurt maker, but the oven in my home. Taste was a bit different each time, and it tends to become better after a few days. Even used the sun’s heat last summer, but temperature was still to low to turn the milk into yoghurt in a day, the taste wasn’t right. I just kept the milk/yoghurt in the fridge, and somethink like 5-6 days later the taste was good!
I’m not making my own yoghurt right now. It’s a bit of a hassle and keeping the oven on all-night, nah. I could buy a yoghurt maker, but I’m now buying yoghurt from a smaller-scale company located in a small town in The Netherlands with some 400 residents. They ferment the “real farmers’ yoghurt” for 18 hours. The yoghurt is quite thick compared with the normal yoghurt you can find in the stores and the taste is very nice, close to what I made myself a couple of times.
I’ve made yogurt before, but I really didn’t want the hassle of yogurt with all the worrying about temperature, so I started making KEIFER. Much simpler.
I just put some of the kefir “grains” (they look like cottage cheese) into a mason jar with some milk, put a loose cover on, and stick it in a cupboard for 2-3 days. I don’t have to worry about temperature or anything else. Warmer is better, but it’s not critical either way. And the longer you leave it, the more fermentation happens, so time is not an issue.
The research I’ve done indicated that it actually has more kinds of bacteria than yogurt, though I wouldn’t bet the farm on that. Here’s a brief discussion of that which echoes other sources: https://www.kefir.net/kefiryogurt.htm
You can have a couple going if you want, but I use a quart=sized mason jar, and that works out perfectly for me. And the grains/starter just keep growing and multiplying, so you can give the extra away, or just toss it. I’ve been making kefir from the original batch of grains for almost 6 months now. Apparently, they pretty much last forever.
I got on to this whole bacteria kick from you, Seth, so I appreciate you continuing to discuss this.
I tried making kefir. It was too hard to get the grains. And they didn’t seem to multiply as they are supposed to. In Beijing it would be even harder to get kefir grains than in Berkeley. I’ll just say yogurt = kefir for dummies.
Seth,
This year I cured my seasonal allergies thanks to yogurt, which I started eating regularly due to following this blog.
I use a yogurt maker that was sitting in my in-laws attic, unused. Very easy: I just mix two tablespoons of yogurt and a half gallon of milk. The machine only goes for 8 hours (the instructions say it’s done then), but I run it a few times, between 24 – 36 hours — less than 24 results in noticeably less sour yogurt.
For the past 3 years or so, a co-worker and I would suffer spring allergies together. We seemed to be allergic to the same thing, bc we’d start and stop at the same times. This year, we both got whacked hard late April. Desperate, I started eating yogurt (breyers mostly, some danactive and stonyfield) every day, sometimes twice, after reading your blog and doing some research. About 8 – 10 days later, I noticed I had no symptoms. My friend had light symptoms, so I thought maybe it was just a lull. Then about 2 weeks later, my friend got pummeled by allergies again, very badly; he could hardly work. I had NO symptoms. I didn’t even realize it was a bad day for allergies until he showed up to work. I haven’t had any allergies since.
So now I make my own yogurt, to save money, and bc it’s so easy. Next, I’m trying to do sourdough bread, but the starter is taking me a while to get going.
Thanks for your blog and sharing your personal results!
Mike
you’re welcome. thanks for letting me know about this.
“I’ll just say yogurt = kefir for dummies”
I had to read that a couple of times until I was sure I wasn’t being insulted. Funny! But I think it’s the other way around. I hate having to deal with temperature issues, and having another electrical appliance.
When you get back to the states, email me, and I’ll send you some grains. Mine multiply like crazy, and I end up throwing them away. Starting out with good grains is definitely the key, and the ones I have are prolific. They have essentially doubled every 3 or so batches.
Charles, thanks for your offer of kefir grains. I’ll take you up on it so long as I can remember. I think yogurt may be the most popular fermented food — leaving aside beer and wine — just because it can be made the fastest. I would like more variety in the fermented food I eat.
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Listen listen guys !
You got the right idea that sourer is better, and then it hits a plateau where and when it becomes too acidic for the bacteria that make lactic acid to continue to be able to survive in the pH,
OR they simply consume all the food available to make lactic acid and then when they run out of food and there is most lactic acid around, = sourer,
then they stop feeding and slowly die off,
the lactic acid however remains behind, but it slowly dissipates, because it’s probably buffered by something else in it like calcium,
then it gradually becomes less and less sour, allowing pathogenic bacteria to multiply more easily…
So to simply put, it’s true, – wait for your yogurt to get quite sour, but don’t wait for more then 24-32 hours per batch,
Lactic Acid is one of the most amazing molecules in our body, – it provides DiRECT energy to the neurons in our brain, after it’s converted from glucose ( wikipedia )
So that’s another main reason why sour is healthy, just make sure it’s lactic acid and not acetic acid ( you can taste the difference ! (:
ENJOY ! – For Your Health .
Seth: yes, 24-32 hours/batch is a good length of time, based on my experience. The yogurt gets more sour up to about 30 hours, then doesn’t get any more sour.