I use the crockpot method: Heat a crockpot to 82C, let it cool to 48C, stir in a tub of good-quality, plain yogurt, wrap the crock in towels, and leave it in the oven overnight. Then, in the morning, I put a long mesh collander in a glass cake pan, line the collander with cheesecloth, pour the yogurt in and let it sit in the refrigerator for several hours. The cake pan will be slowly filling with whey over the course of the day.
If you’re worried about disposing of the whey, you can drink the stuff, or use it in place of things like buttermilk in recipes.
That’s what I do; I use 5 cups of powdered milk to 12 cups of water. It works just fine.
Hm. I bring it up to 180º and leave it there for five minutes to pasteurize it, and then let it cool to <120º. Then I mix in some yogurt from the previous batch (about 12oz yogurt for 192oz milk) and put it in a proofing box at 115 degrees for three hours. It comes out exactly the same every time. There’s nothing unpredictable about bacteria—if you are getting unpredictable outcomes, you’re not controlling one or more of the variables. For me the proofing box was what made the difference—because it’s thermostatically controlled, there’s no variance in the temperature.
I get good thick yogurt using this technique—actually the reason I only let it go three hours is that I like it a little less thick. When it’s done there is some visible whey, but it mostly dissolves back into the yogurt during the first 12 hours in the fridge. I’ve never needed to add powdered milk to this. I am using very good milk from a local dairy that comes in glass bottles—the main reason I started making yogurt was to reduce my trash stream.
I have not had good luck with yogurt starter, because it comes with added sugar, which throws off the flavor of the yogurt. Yuck. I just get some local yogurt to use as starter. If you are west of the Mississippi you can get some Straus yogurt from Whole Foods. You only need this once—afterwards you can use your own yogurt as starter. East of the Mississippi the Trader Joe’s organic yogurt works. I use a local brand called Side Hill Farm, which seems to have a nicer culture than most commercial yogurt I’ve tried.
This slow cooldown idea is interesting, though. I’m tempted to try this. My proofing box is collapsible, so it would be easy to take the sides off and just leave the yogurt for a while longer.
I have read that the purpose of heating the milk is to denature proteins that would interfere with the yeast. I doubt these temperatures would kill the bacteria. Maybe.
Totally fine. Providing the yogurt isn’t so heavily processed as to have killed off the bacteria you need flavoured/sweetened yogurts will not make any real difference to the starter culture.
When I need a new starter culture this is what I check for:
When does the yogurt I'm buying expire?
Generally I pick anything with a "best before" anywhere between a week or three weeks away. If it's less than a week, the yogurt has probably been on the shelf for too long, and the culture inside will be dying and thus might not work great^. If its longer than three weeks I tend to assume the brand of yogurt adds a lot of preservatives/or does something to steralise the product, and I'm never sure how well the culture survives these processes, I've had both successes and failures with yogurt in this category.
Does it claim to be "full of good bacteria?" "probiotics" "etc"?
If it claims this one can assume it hasn't been processed to the point of killing the necessary culture, although the above still applies.
Will I enjoy eating what I don't use for a culture?
You only need a tablespoon or two, may as well enjoy the rest!
The flavouring/sweetening of the culture tends to make no difference to the final product.
^Interestingly I’ve certainly had a few dud batches that didn’t really work, which I’ve blamed on an old batch of culture. However they’ve still been edible (just runny and more whey than curds); and I’ve then used the new less successful batch to create a normal and successful batch afterwards, so culture colonies can be restored from the brink! I like to think I’ve saved a decaying society of yogurt bacteria from the brink of extinction before I greedily gobble them up.
Also, don’t use/drink raw-milk. Just don’t. Unless you’re making speciality cheeses^ there is just no need, and you introduce the opportunity to make people sick. Raw milk is not healthier, it is potentially deadly; this is what scientific evidence says. If you are using raw milk, keep the temperature above 75*C for at least a minutes whilst stirring to kill off any potential nasties. Congratulations, you’ve now pasteurised your milk and you’ve joined the scientific community in accepting that this is better for you.
^Some cheese making processes do have different outcomes using unpasteurised milk. These cheeses should then be aged, which due to acids and salts within the cheese will essentially achieve the same bacterial killing outcome. If the cheese is a fresh unpasteurised cheese, I still wouldn’t eat it.
Yogurt made with heavy whipping cream is good. Very thick, very rich. It can be beat into whipping cream, or, if you whip even longer, churned into butter. The cultured butter is good, and the buttermilk makes the world’s best salad dressing. And boy, that heavy cream yogurt tasted really really good on grape nuts. I culture a gallon of the stuff every thanksgiving.
Thanks for this method, I will try this as I am not to happy any more with the yogurt maker we have.
One of my favorite things to do with homemade yogurt (or with store bought) is Labneh or strained yogurt, as used in middle eastern kitchen. The process is similar to how you describe you make greek yogurt, you place a cheese cloth in a colander and pour the finished yogurt through, then you squeeze it for a bit and allow all the whey to drip off for 1 to 2 days (the whey can be used in various ways as well btw), unrefrigerated works as well, but if it is very warm, best to do this in the fridge. You end up with a cheese like loaf that can be spread on toast. Or you eat it with sliced tomatoes, parsley and garlic. But my favorite way is to form it into small falafel sized balls and roll it in Za’atar, the middle eastern spice mix.
I haven’t tried straining it, but i have made ricotta which involves the straining with a cheese cloth. I think one of the uses for whey is making ricotta but i prefer to do it with milk as you get a better yield. I tried making porridge with whey but it was horrible! Any other good uses you know of?
Thanks for the extra info, really interesting. I don’t use raw milk for yogurt, but i do use unhomogenised (still pasteurised). This gives a nice flavour and texture.
I would really like to try raw milk though - here in the UK there are a handful of farms that are strictly regulated for hygiene and can legally sell raw milk. I am curious to see the difference in flavour and i am not overly concerned about the bacteria in these super-hygienic farms particularly as i live near to France and eat a lot of unpasteurised french and english cheeses.
as far as my GCSE biology goes, i think a lot of bacteria is killed above 65C - however, pasteurisation has a strict regimen which involves superheating the milk beyond this (and beyond 100c, as you imply)
Our milk does not contain added vitamins and chemicals, and the yogurt that i use lists the strains of bacteria present - it is specifically sold as ‘live yogurt’. Thanks for the tips for those in America though - i didn’t know that US store bought yogurt doesn’t have the right strains, and i did wonder about the milk as i wrote
I bought a yogurt maker for cheap at a discount store. It was intended for babies but as there is no difference between baby yogurt and grown up yogurt, I thought it was worth the $5 to have something that would regulate the temperature of the yogurt. It came with little jars, which are nice. You can also just sit one container inside to make a bigger batch.
I also bought a yogurt maker for my dad for a present and he makes it most every day - it has been a real life saver for him as he has problems with his teeth and is on a soft diet. He likes the science-y aspect of it too.
My next project with the yogurt is make frozen yogurt. I haven’t tried this yet, but I have a book that uses a meringue, similar to this recipe, to give enough air into the recipe to make the texture more like the commercial soft serve kind. http://bakingbites.com/2012/07/homemade-frozen-greek-yogurt/
Whey can be used for lacto-fermenting vegetables, my current favorite recipe is not quite seasonal, beets and horseradish, grated then placed in salted water with whey added for the fermentation process.
there it suggests that you heat the milk to 200F to change the structure of the milk proteins and thus prevent the yoghurt from splitting into curds and whey. Also suggested is keeping the temp up for at least 10-15 minutes (before cooling to 115Fand inocculating) as this will produce a thicker yoghurt. It may jsut be due to evaporation of water but I don’t think so. I concur that only a small dribble of whey is produced (I use a incubator called Yogomagic which holds about a litre at a time) but perhaps this has to do with my timing which is usually less than 3 hours as there is less acid produced and I prefer the creamier taste to the sour of most yoghurt. Am I missing something here do you think? Is this acid important? I would love to not heat it for this long but the results are great.
Quite right. You don’t need to pasteurise already pasteurised milk. But you can get around the milk sticking to the pot issue by heating it in the microwave. Simple.
A caveat on the pasteurising though - I don’t heat new milk, but if I’m making yoghurt from the last litre of a two litre bottle that has been in the fridge for a week I do. And you should.
I use exactly your proportions of milk powder/milk, I use homogenised full cream milk but skim milk powder. It’s the protein content that makes for a thicker yoghurt, and skim milk powder has more protein by volume.
I happen to have a water bath (surplus from work) that I use to incubate yoghurt (and cheese, and to cook meat sous vide sometimes) and quite often forget to take the yoghurt out in the morning - an extra 8 hours just makes it a bit more acidic.
Have to laugh at the article where it says raw milk is supposed to make better yoghurt, then proceeds to instruct us to cook the milk
I’m surprised that nobody has mentioned the health benefits of homemade yogurt. My friend suggested it when I was having stomach problems, and it really does work! I ate store-bought yogurt anyway, and had tried Yakult drinks to no avail, so I was very skeptical, but the fresh stuff made an immediate improvement that has lasted over 6 months (with regular intake of yogurt).
I found different brands make very different tasting yogurt, my favourite is Total/Fage Greek yogurt, and I agree with others that you don’t have to be very precise at all. Mine has never failed so far in dozens of batches, just using a jam thermometer and Thermos flask.
