How I Make Yogurt (2019) | Hacker News Reader

How I Make Yogurt (2019)

rmosolgo.github.io

118 pointsciconia104 comments

A few updates since I first wrote this up:

- I don't bother sterilizing any more. I make sure the jars are clean, but that's all. I think the culture is fast enough to raise acidity to a safe point very quickly. (I still sterilize for cheese though.)

- I always use commercial culture now. I had off-results after the third round of saving a starter. (Someone mentioned heirloom cultures, which I think would avoid this problem. My wife tried those, but we didn't care for the flavor, and I prefer the workflow of two gallons at a time, done overnight.)

- If you make yogurt, but never started with the high-temperature initial step, I really recommend trying it. It makes a thicker consistency because the proteins are denatured and curdle better. (The downside in my opinion is that it also destroys some of the goodies present in my previously-raw milk.)

- My 20-minute high-temperature hold is often much longer. I try to reach 180 degrees F and take it off the heat, then put the kids to bed. It always seems to do fine.

Anyways, thanks for all the comments. I'm always happy to read a nice discussion about dairy processing! Next time you're passing through central Virginia, let me know and we can share a cheese plate.

How critical is the rate of cooling? Do you have to use an ice bath or can you use air cooling to cool it down?

I make my own yogurt using an instant pot for both the boil and incubate but cool using the air. Sometimes the consistency is lumpy, and I wonder if this anything to do with it.

I use my Instant Pot in pretty much exactly this way, but have never had lumpy yogurt, so maybe something else?

That's good to know, thank ou. Maybe it's my starter culture. I had been using yogurt from Dannon or a Skyrr.

Try (if you can find it!) Stoneyfield plain yogurt, not their Greek-style. It tastes great, and I have a 100% success rate with that as a starter. Good luck!

One of the first times I tried using an Instant Pot, I was also using a starter (powdered, commercial) I'd not used before. It turned to cheese curds. I came to the conclusion that the Instant Pot got too hot for that particular culture. So, yes - it could be a combo of both temp and culture causing your lumpiness. I've noticed too with a different culture (yesterday's yogurt) that even after mixing thoroughly, it seems like it clumps back together and I've not been able to discern why.

My instant pot isn't consistent in temperature for saute or high heat. I heat up the milk in a separate pot and use an instant read thermometer to ensure it hits the correct temperature.

When you mix the culture into a small part of the milk, make sure to get that to a fairly smooth consistency before adding it to the rest. That also seems to help achieve a smoother result.

I found that saving a starter really depends on what you start with. In our case we were using store bought yogurt (the yeo valley brand) and after saving the starter 2 to 3 times, it wasn't much active anymore. One day we bought a yogurt from a local farm and have been able to save a starter and re-use it for months, we are still using it. We make yogurt every week.

Same experience with starting from store bought yoghurt, only got 2-3 rounds from it.

Do you know why that is? Is it the quality of the culture on the store bought? This also happens with me, however, the 2 rounds that I get from it are very good, thick, creamy yogurt, so I assume it has to have live cultures. Maybe I'm wrong?

You have to make each round using yogurt from the previous round, not the preceding ones (1), else the bacteria in the culture probably get too few / weaker due to less than optimal conditions, like temp., hours out, etc. (1) That is, batch 2 using starter from 1, 3 from 2, etc.

E.g. google videos of how to make kefir and see what they say about how to preserve and replicate the kefir "grains".

Exact same technique may not apply to yogurt culture, but principles do.

I live in Turkey where yogurt is an essential part of our diet and culture and nothing beats a homemade pot with a thick layer of cream on top.

I can assure you, you'll never need to buy any more starter, ever! As long as you save some for the next batch, you're golden! If you can use unprocessed milk purchased directly from a dairy farm, that's even better as I promise your tastebuds will rejoice! :)

I don't bother sterilizing any more.

I'm glad to read this. I used to "make yogurt" by mixing a small container of yogurt into a gallon of milk and leaving it out on the counter for a day. The result was perfectly cromulent yogurt. Then well-meaning friends urged me to worry about sterilization, and I haven't made it since...

> If you make yogurt, but never started with the high-temperature initial step, I really recommend trying it. It makes a thicker consistency because the proteins are denatured and curdle better.

I wonder if using UHT milk (which is heated up to 135°C/275°F) would achieve similar results. It has the bonus of being sterile straight from an unopened packet.

I've been making kefir with UHT milk for a couple of years now, and it always seems thicker and creamier than some others I know who use fresh refrigerated milk.

Since you seem to be really into making yogurt and like your science, I wonder, have you ever tried using "dew" as your starter?

There's an old (unfortunately dying) tradition in Turkey where dew you collect at sunrise during late spring, early summer can be used to ferment fresh milk to make the absolute best yogurt.

How my wife does it:

1. Boil milk in a pot (3-4 liters). Forget it's there. Turn it off when someone notices it boiled.

2. Wait till it cools to ~40c. Try to put a finger in the milk. If it's cold enough so you don't have to take your finger out, it's about ready.

3. Dump a cup of probiotic yougurt inside and stir.

4. Cover with the lid. In the winter wrap it with some blanket to keep it warm (probably not really necessary)

5. Wait for 24 hours.

6. It's ready. Put the whole thing in the fridge.

Somehow this works every time... It's seems really hard to ruin the process, and not for lack of trying...

Hard to ruin recipes are the best recipes.

That's almost exactly how I do (The difference is that I use a thermometer).

Are you using some local milk? I use "bio" milk and I'm pretty sure (by the expiration date being at least a month into the future) it is UHT, so no need to boil the milk?

Using whole milk (also works fine with regular milk), refrigerated, so probably not UHT.

You should boil the milk anyways, you want all other bacteria/bugs dead and only the "wanted" bacteria to "spoil" the milk. Otherwise the result could be unpredictable.

Boiling the milk also helps the bacteria to work faster.

> You should boil the milk anyways, you want all other bacteria/bugs dead and only the "wanted" bacteria to "spoil" the milk.

UHT milk tends to be sterile, if it's straight from an unopened carton.

Boiling denatures some of the proteins, and gives you more of the texture you expect. From what I understand, if you don't boil it the texture will be very runny.

ELI5 - Boiling makes it easier for the bacteria to eat.

Also evaporates some of the water.

This is how my mother does it too.

You just need good bacteria to start with, called the "culture", for your next preparations you can just get a sample from your previous yogurt.

The yogurt you get from stores with preservatives and ultra long shelf time, a.k.a. all bacteria is cleaned up to prevent it going sour, wont work, find someone that has real yogurt.

That's the reason for using a probiotic yogurt. They add the relevant bacteria after they finish ruining it :)

The problem with using yogurt from the last batch is that usually there is nothing left when you finally get to making the next batch... :)

Well, we usually just keep at least one teacup of yogurt to avoid the situation where none has left as you have mentioned be able to make more :D

Yeah, well... The kids have a tendency to find and eat anything that happens to be in the fridge :D

This sounds brilliant - I'll give it a go tonight!

On a different note, I grew up in Eastern Europe before it became capitalist and used to spend my summer holidays in the countryside. Needless to say,almost nothing was pre-packaged or ready made and everything was made from scratch, including yogurt. I can't really remember exactly how my grandmother made it, but I think she followed a similar process. I remember very fondly how it tasted, cool and slightly tart on a hot summer day; obviously these memories make me want to try it even more!

Somebody once told me that smokers smoke hoping that each cigarette will taste like the first. I can't really comment on that, but personally, every time I eat yogurt I hope it will taste like it did in childhood.

For anyone wondering why this works, and why the link's technique is so complicated, remember that humans have been making yogurt for thousands of years. So you don't need anything fancy to make yogurt.

Even a fridge is not needed. Put the milk+yogurt mix container in a clay pot placed in a tray of water, and it will turn into yogurt.

Anything fancier on top is just to reduce the amount of work needed or have longer fridge life.

The old, traditional yogurts were made by using soil (yes, literally earth). The soil had the bacteria required :)

Right, many recipes in this thread are fancy. No need to get in such a ferment about it (pun intended). May be needed for colder northern climes, but I have my doubts. (E.g. people were making yogurt in similarly cold Central Asia for centuries, with out such data structures and algorithms, er, containers and instructions.) In India, mothers and housewives (and nowadays househusbands) routinely make curd (Indian English name for yogurt, dahi in Hindi), just by warming (c)old milk (or cooling just-boiled new milk down some), bunging some old curd in (e.g. 1 to 2 tbsp per liter milk) putting it in a slightly cooler or warmer part of the house, depending on the season), and forgetting about it for 8 to 24 hours. That's it. Dead simple. If not come out well, tweak a parameter or two, retry. But mostly it goes smoothly (pun not intended but retained).

I'd like to hear more about why you make your own yoghurt. Does it taste very different than store bought plain yoghurt, do you find the DIY aspect appealing, or is it mainly for cost savings?

You can clone any expensive yogurt for small price and control the ingredients fully.

I do it to make full-fat, low-sugar yogurt, which is harder than it should be to find at the grocery store. Almost all of them besides the Fage Greek are loaded with sugar. Guess which one our store doesn't stock? (the Fage 5%)

In Spain you can find everywhere "natural yogur", not sweetened, with "4 g sugars", I guess lactose, per 100 g, so 5 g per 125 g cup. Is this low-sugar by your standards or is it possible to achieve lower contents?

Yes, I'm referring to "no sugar added" really. As you mentioned, there is some natural sugar.

I personally do it because I get a better consistency and taste, with lower lactose than in commercial varieties, and save a couple of bucks. It's really easy to make, I use a teaspoon of the previous yogurt batch as a starter and let it ferment 13 hours in 1L of milk, in the oven with the oven light on. Too much starter and it ferments too quickly, gets chunky and sour.

Most yogurts here contain various additives for firmness, which usually means some kind of processed sugar, which I prefer to avoid. There is also the quality and the price aspect.

Also, it's fun.

You need yogurt to make yogurt?

Instant Pot is great for this. 1. 4L of yogurt, press button. 2. Wait to cool to 40C (place whole pot in sink full of cold tap water if you're in a hurry). 3. Stir in 1-2 tbsp yogurt, press second button. 4. 8hrs later/next morning, yogurt is ready. Transfer to whatever container you want.

You can strain it further with one of these dealios, or a homemade contraption: https://www.amazon.ca/Euro-Cuisine-GY50-Greek-Yogurt/dp/B009... It makes it milder and absurdly thick.

Sometimes I like to leave batches for 60hrs instead of the usual 8. It makes it incredibly acidic, but after straining thoroughly, most of the acidity is gone and you're left with a very strong tasting, goat cheese-like product, ie yogurt cheese. Mixing this with finely grated garlic and salt is sublime. I've given this to many friends and acquaintances, it's always a hit.

Came here to mention the Instant Pot. My only difference is to put the cooled milk into pint jars, then add a teaspoonful of the previous batch of yogurt to each one.

I'll have to try the 60-hour thing... sounds interesting!

Yep - Instant Pot makes it really simple. Do make sure your model has a yogurt button (not all do). It works something like 95% of the time. You'll easily make up the cost of the Instant Pot with just yogurt if you eat as often as I do.

The only modification I make is that after the milk has cooled down to about 110F, I pour the milk into containers, and put the containers in the Instant Pot. I add water to the IP to make a water bath. This way when the yogurt forms, it is in my final container I want it in.

Some other "tips": I do 6.5 hours - it is enough. For the cooling, I simply put the hot pot in the fridge and wait an hour - easier than continually checking the temperature. I've timed it such that an hour will get it to about right. In any case, it's OK if you forgot about it and it gets cold - you can still make yogurt - you only have to adjust the time (so instead of 6.5 hours for me I may do 8 hours with cold "boiled" milk).

That's interesting about the cheese-like product. Just recently I left some paneer in the fridge for a few days too many. When I took it out to use it in a dish, I saw it had a cheese-like consistency (harder than the original paneer) and smell. Used it in the (Indian) dish anyway, tasted different but fine.

For those interested in avoiding the complexity of dealing with industrial bacteria strain that can't survive easily in normal conditions, I recommend looking into traditional yogurts.

. They don't need sterilization at all

. They mature at room temperature

. They taste great and have a range of different textures and flavour depending on the strains

. They are stable among generations and can be reused indefinitely

My favorite is Viili but the slimy texture is challanging for some.

This is a great low scale shop that I use:

http://gemcultures.com/

That website has a delightful geocities look to it.

I've never bothered with sterilisation to a great deal (just hand washing with washing-up liquid), I just use UHT milk (I think it tastes better for yogurt, and it's already obviously more sterile than fresh milk). I just add a spoonful of yogurt to 1-2 L of milk (I don't bother heating it beforehand), leave it in my PID-controlled crock pot [1] overnight at about 42°C, then it's done. I usually leave the yogurt in some coffee filters for an hour or two to get more of the whey out and make the yogurt thicker. If you leave it for 2-3 hours it's essentially solid, and absolutely delicious.

[1] No write-up yet I'm afraid, but it's a custom PCB I made with a simple temperature sensor, Atmel microcontroller and mains relay that switches on and off my crock pot. It's powered from the mains via a cheap board-mount switch-mode power supply, so no extra power required. Board files here: https://github.com/SeanDS/slow-cooker/tree/master/hardware/v....

There is no comparison between home-made and store bought yogurt. More than anything a proofer box [0] has made the process better. Author mentions the Brod and Taylor recipe, but not the box. The box is what makes that recipe easy. The "Set it" step is where I find things tend to go awry. The box will hold the temp, which will allow you to control the consistency of the finished product. Also it makes it easier to do larger quantities.

[0] https://www.williams-sonoma.com/products/brod-and-taylor-fol...

Or just use instant pot. I use it to make a small batch (1/2 gallon) of yogurt everyday for years now and it have never failed me. Thought I add the culture at 110F.

This seems hugely complicated. I make yogurt daily.

Warm up milk to lukewarm. Mix spoonful of starter. Bundle the vessel in a thick towel for insulation. Leave it overnight. (Or less, if you live in a very warm place).

If it is cold, I warm up the oven just a tad and turn it off, and leave the vessel inside.

Use a spoonful of that yogurt the next day as starter.

Do you strain yours, does yours naturally thicken to a consistency you like, or do you like it kind of thin? I ask because this is the part I find the most frustrating - the making it is easy, the getting it to the consistency I want is work.

The image shown in this link is the consistency I get.

https://www.indianhealthyrecipes.com/how-to-make-thick-curd-...

As this site says, if you want it thicker, use whole fat milk, or boil the milk on low for a while before letting it cool to luke warm temp.

Good info -- yes I've gotten sloppy about milk selection as I often make it with just whatever we have on hand that needs to get used up.

Ofcrpls deleted their message before I could get my response out, but…

Maybe I need to be clearer in my intensions here... I like to make a yogurt that is thick like a sour cream. I know that commercial producers often strain theirs as well (or add xanthan gum) in order to get the consistency they want. On that same note - I have really liked the sheep milk yogurts over holstein milk yogurts because the difference in fat content does make a consistency difference. BUT, I've also contemplated that there are different cultures that might also be part of this difference as I've seen that for myself as well but have not been able to identify which cultures might be making the difference. All that was the reason for my inquiry.

I find you can even make yogurt from slightly sour milk, just by adding a little baking soda.

Details: to make good yogurt you need to bring it to 85-90C, which denatures the milk proteins and improves thickening. If the milk is acidic, it will separate into curds and whey when heated. Sour milk is acidic, so adding a little baking soda to raise the pH allows you to heat the milk without separation. Then, during the later fermentation process, the pH falls again, and the yogurt is tart.

My method is very similar, but I find even just a tablespoon of yogurt from the previous batch is enough to inoculate 1 gallon.

We also drain off a good portion of the whey using a nut bag to make Greek yogurt. The leftover whey we put in smoothies.

I LOVE being able to control how much sugar is in it, and it’s way cheaper than buying individual packs. All in it costs us right around $2.50 for a gallon of yogurt at home.

This is how I make yogurt:

Step 1: Put 1 liter of milk mixed with 0.2 liter of Yogurt on a heating radiator at 11PM.

Step 2: Wake up at 7AM. Yogurt is ready.

Yes, the original post seems a lot of extra effort to make it thick and set. My simple method:

1. Warm milk to 120°F in a pan with a spoon of yoghurt

2. Put in thermos flask 8 hours / overnight

3. Put in a jar and leave in the fridge until cool enough to enjoy

What Yoghurt do you use in Step 1?

The first time, you can use a Yogurt without artificial flavor. Afterward, you can reuse the Yogurt made the first time. Or just use a common Yoghurt from the store. You can use less than 0.2L the first time because the artificial flavor mixed with the natural Yoghurt flavor will not taste that good. The second time and afterward you can use the Yogurt made the first time, the artificial flavor will be diluted.

EDIT: Warning, I do not know how many times can you safely reuse the Yogurt. I've reused the 'same' Yogurt several times without any issue, but please do your research. Of course, I store it in the fridge.

Nice writeup, good tips.

I recently started making my own yoghurt. Here's my bits:

I buy the Costco 3-pack of organic whole milk. I'd never get thru that much milk otherwise. Works out to about the same price as their greek yoghurt, but theirs is low fat and I want the full fat for the extra calories.

For my starter, I now use a store bought brand I really like, ellenos.com. I tried a few dry starters. Blech. Though I will now try cheesemaking.com's Thermophilic stuff too (linked in article).

I can't figure out an easy, practical way to drain the whey. I don't mind the juice so I've stopped trying.

Now I use my Instapot.

I bought the wrong model of thermometer. https://www.thermoworks.com/DOT Has a temperature alarm. But it only works for rising temps, no way to alert for cooling temps. Surely someone knows how to hack it. Recommendations please.

I make and consume kefir every day. It's a lot less involved than this and has the same familiar tang that plain yogurt has.

I also notice a sense of well-being shortly after drinking it. I noticed this prior to learning that kefir is Turkish for "feel good".

BTW there's no evidence that the word has Turkic roots. "Keyif" means "enjoyment" but Kefir has no shared roots with it and "keyif" itself comes from Arabic.

Whatever its original root is, last verifiable root is Russian "кефир", according to Sevan Nişanyan ( Turkish: https://www.nisanyansozluk.com/?k=kefir )

What is your method? I’m a champ at making yogurt, but my first foray into kefir went horribly wrong.

1. Put kefir grains in milk.

2. Wait maybe 24 hours at room temperature, depending on preference. I regularly do 48 with no problems.

3. Remove grains and eat.

Can you reuse the grains? If so, how many times until they stop working?

I've been using a set of grains since 2017 or so.

Since they're essentially a symbiotic culture of bacteria and yeast (SCOBY), they won't "stop working" as long as the grains are regularly replenished with milk, or kept in the fridge to slow down the fermentation process.

I get the same sensation when eating other fermented foods, like sauerkraut (which is also very easy to make, just pulverized cabbage and salt). I assume it's my gut flora sending happy signals to my brain.

I tried keeping kefir grains for several months and it never really turned out in a way that I thought was worth the bother.

I absolutely love the kefir you can buy bottled in stores, but maybe that isn't really anything like traditional kefir?

You can also make Yogurt out of soymilk. Not every milk that you can buy in the store will work, but it works just the same way.

What works for me is:

- Heat up the soymilk to 45 °C

- Put in the yogurt culture or a tablespoon of the leftover yogurt

- Add a tablespoon of sugar

- Fill into an isolating container and wait for 8+ hours

- Put the yogurt into the refrigerator

- Consume yogurt but save a spoon for the next batch

I've found that when starting from culture it takes a couple batches until the yogurt gets really good. After that there didn't seem to be an upper limit on how long you can keep making yogurt from the old batches, although it can get bad if you wait for too long with starting a new batch.

I've actually found that it doesn't usually make a noticeable difference for soy yogurt whether I heat the yogurt to 45 °C or some lower temperature or even at all, at least when using a electric yogurt maker (or other device with active heating). Maybe I need to try them side-by-side because I assume there's some reason many people suggest heating the milk first.

I just mix the existing soy yogurt with soy milk, both of which only consist of soybeans, water, and cultures which seems to be the most reliable option. It involves virtually no effort this way.

With a yogurt maker there’s no need to preheat it since the appliance will take care of heating and maintaining the temperature. But if you make soymilk yourself, the milk has to be cooked for sometime (regardless of whether you’re going to consume it directly or make yogurt with it).

> You can also make Yogurt out of soymilk. Not every milk that you can buy in the store will work, but it works just the same way.

You can also make it with peanut milk, coconut milk, cashew milk and other combinations. The process is the same, but the results will be different because of the inherent nutritional composition of the base ingredients. Store bought milks may have additives that hinder this process. It’s better to make the milk at home and then start it.

Hello, former home yogurt maker here. I used to do this weekly, using a recipe from Harold McGee in the NYT. The incubator was a home oven left warm overnight. It was pretty painless with a success rate of 100%. But, the result was always mediocre, no matter the starter culture. (I didn't buy pro culture, just made it from different brands of yogurt.) It was always pretty thin, never creamy enough, never tart enough. The next step is of course to strain out some of the whey and doctoring the milk fat. Out came the cheesecloth and the bowls, and ... now I've done it. What was I going to do with the whey? The counter was always littered with stuff, the cheesecloth had to be disinfected and washed and hung dried. I got thicker yogurt, but it still didn't taste great. It dawned on me one day that I was spending a lot of time and money (organic milk, expensive yogurt starter) and putting up with a lot of silliness to get an OK homemade product. I chucked it all. Now I buy the European Style yogurt from Trader Joe's and their brand of plain Greek yogurt, both at $3 a container. I love how those taste. I don't regret having tried to make yogurt, and then quitting. That's been my experience and perspective, and I'm in no way devaluing or deflating the experience of the folks here. I think it's pretty awesome that people are still making their own food. My next dairy misadventure: burrata.

There are machines that just do this process for you that work well, I have one similar to this[0] and it's very easy to use.

0: https://www.amazon.co.uk/VonShef-Digital-Yoghurt-Maker-Jars/...

The machine I have is so easy that I ended up getting two. I just pour a quart of UHT milk in each one, don't bother boiling, add yogurt starter, turn on, put great thick yogurt in the fridge 9 hours later.

My wife makes yoghurt in an Instant Pot, she uses lactose-free milk, full-fat Fage yoghurt as a starter and I think some other ingredients. (I'll check and update later)

End result is a Greek/Skyr like yoghurt that lasts both of us for more than a week. It's so tasty!

> she uses lactose-free milk

I am lactose intolerant but yogurt is fine for me. As I understand it lactose in yogurt is easier to digest with the yogurt bacteria.

Curious do you have intolerance with regular milk yogurt?

I thought lactose was what yogurt bacteria ate?! How does this work?

Bacteria eat sugars, not just lactose. There's other sugars in milk.

I'm also lactose intolerant and I'm sensitive enough to where different brands and types will yield different... results. Icelandic yogurt/skyr sits the best with me, it also has a more complex culture cocktail than most yogurt so it might be related to that.

She is the lactose-intolerant one, she's chosen this recipe because it does indeed bother her the least.

She uses Fairlife milk, sweetened condensed milk, and a full-fat Fage yoghurt. It's great!

How I make yogurt:

Requires:

* a Digital temperature regulator * a non digital crockpot (mechanical on/off switch)

1. Dump milk into gallon jar. 2. Stir 1/2 C yogurt into milk. 3. Put jar in crockpot 4. Pour water around jar 5. Insert temp probe into water 6. Plug crockpot into temp regulator and temp regulator into wall 7. Set temp regulator at or below 115 deg F 8. Cover with towel or apron to hold in heat 9. Wait 12-36 hours to taste.

Total working time: 5 min. Total cost per gallon: < $2.00

You don’t have to pre boil the milk if you’re going to use a commercial probiotic yogurt rather than chaining. That’s the biggest time and effort saver: not having to watch a slowly heating pot of milk and preventing it from boiling.

If you don't want to spend 30+ minutes a pop sterilizing everything, you can always go the homebrewer's route and pick up a bottle of Starsan, a food-grade sanitizer.

A bottle lasts for quite some time, and if you make the solution with distilled water, its shelf-life is quite a bit longer. When you want to sanitize something, just throw the dilution into a spray bottle and spray down your containers and wait for 30 seconds - no rinse needed.

Just a thought to save time for those who might be doing this often.

I love making yogurt, and have tried it on and off since I first had fresh homemade yogurt made by my Oma on my first trip to visit them in Germany back in the 90s. Every day started out with fresh yogurt with muesli, and my mind was blown. But here in Canada because of supply chain management price controls on milk it's just not that cost effective compared to buying pre-made yogurt. And there's not the same variety of fresh milk products available here either.

How I do it:

  1. Heat 14oz of milk for 2 minutes in a 700W microwave
  2. Add 4oz of cold milk to a container
  3. Add 2 spoons of Yogurt (I use Pavel's full cream) to the cold milk and mix
  4. Pour the hot milk in the container and stir it
  5. Put away in a place where the temperature won't fluctuate much and container won't be disturbed for next 12-18 hour. 
     I use an oven for this with no per-heating or temperature control.

Tip for making better yogurt: use a clay pot if you can find one. I can't tell you why, but somehow it creates smoother, richer yogurt.

I have a gas stove whose oven has a pilot light, so the oven is always slightly warm and suitable for culturing yogurt. Here's my recipe:

Put milk in a pot on stovetop on lowest heat, heat until its steaming (or to a boil) then turn off heat and allow to cool to room temperature. Add some yogurt, stir, put pot inside oven and leave overnight. Its all yogurt by morning!

I followed a recipe a few times and had decent success using store-bought as a starter. It ends up taking a long time, cost about the same to make as buying a 32oz tub and yielded about the same volume so I just buy it. Fun and easy project to do yourself, but for me it isn't something I took enough interest in to keep doing regularly.

I use a sous vide machine to keep the yogurt at a consistent temperature. If you're working with non dairy milks, that extra time can help a lot.

If you're looking for another good fermentation, kimchi is a great one. There's nothing better than making kimchi fried rice or kimchijjigae with homemade kimchi.

I do a lot of yoghurts at home. I find skim milk powder is really excellent for thickening it up before you culture it. I also enjoy browning it a teensy bit on the bottom of the pot - gives it a nice caramel flavour.

I make yogurt pretty much following same steps. Unfortunately I only have access to store bought yogurt as starter. It’s fine for a few times after that it gets stringy. I have to find a good alternative.

I use a $20 salton rice maker on warm (not cook) setting into which I put a 2 litre glass jar of ingredients brought to 90 degrees F beforehand. No sterilizing. Takes about 10 hours

Poking around a little in that guy's repo... he actually seems to write that entire blog as plain HTML files! I was really surprised, sort of expected it to be gatsby or something

I wish I could give it a try... I don't have a place of my own yet and no access to a kitchen, but hey! It could be worse. I'll save the recipe for the future though.

Is yogurt the next peanut butter&jelly or craft beer or avocado toast thing?

I've seen a few recipes for making yogurt on my hipster friends facebook feeds recently and now this.

What was the peanut butter & jelly thing?

Fermenting in general has been gaining popularity over the past few years and with shelter in place there's been a sudden spike in interest. I've see a lot more content on making sourdough, yogurt, sauerkraut, kefir and kombucha popping up.

You can avoid burning the milk by keeping the milk moving with a large spoon. Nesting the milk in a second pot of water seems overly complicated.

Has anyone tried using thermophilic starter to make yogurt? How does it compare to using store bought yogurt as starter.

Thanks for sharing. Will be giving this a try. Also, for the author, I like the design of your site. Very easy to read.

Walk into any Indian home for a free lesson, they make it every day for a few thousand years now :-)

How long does home-made yogurt remain active enough to be used as starter for a new batch?

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