Yogurt by the Gallon





Introduction: Yogurt by the Gallon

About: retired chemist trying to stay out of trouble

You've read a lot of stories about making yogurt. I think there are enough innovations here to give you something new and interesting. If you need a gallon of yogurt every week, this is the fastest, most reliable, easiest, and cheapest home process by far. I'll have further musings at the end, but let's get right to it.

You will need a gallon of milk in a plastic jug, a pot bigger than that jug, 2 coffee filters, 2 oz. of plain yogurt in a cup-sized jar, a pair of gallon-sized shallow food containers, an insulated container to hold the jug, a drill or sharp knife, a cooking thermometer, and a kitchen with a stove, fridge, and sink.

The cheat sheet.
1. Sanitize everything.
2. Heat to 180 - 190F.
3. Cool to 100 - 110F.
4. Inoculate.
5. Ferment for 6 - 24 hours.
6. Strain in refrigerator.

Step 1: Scald the Milk to 180º - 190º

Poke the temperature probe through the cap. Reserve a cup or two or three for pudding and place the jug in the pot. Add just enough tap water to barely float the jug. Cover the pot if you can and set the burner to high.

It takes my electric stove about 25 minutes to heat the milk to 175F. Then turn off the heat and let it coast up to 180+. I use a timer so I can turn my attention to other things, but depend on the thermometer. 

It's hard to find the perfect vessel for this, but it really doesn't matter to the yogurt. Mine is a 12 quart aluminum pot, over 10 inches high inside, with a glass lid that has a vent hole. It saves time and heat. You can do this in an open 3 quart pot for a trial run, but it's more trouble.

Step 2: Cool the Milk to 100º - 110º.

You can take the jug out of the pot to cool with tap water in the sink, or just take the pot to the sink. Be careful, it's heavy and hot. I grab the jug with the hook end of a ladle. Once it's out of the water, the jug handle is cool enough for me to handle. Do whatever is safe for you. There is no urgency here.

Cooling time depends on the temperature of your tap water and kitchen air. Plan on a half hour in water to reach 110F, but depend on your thermometer. At 112F, dry off the jug and prepare to inoculate. But the exact temperature doesn't matter that much to the yogurt. 

Step 3: Inoculate

Below 110F, your bacteria will be happy. Of course you want to use a nice clean starter culture, but it doesn't matter to the yogurt. I dilute some of my last batch with an equal volume of the scalded/cooled milk to let it pour easily into the jug. As little as a tablespoon of starter will work — they grow like crazy. I try to save about 2 oz for this because I'm going to eat it anyway.

Step 4: Ferment

Now the inoculated milk needs some quiet time in a cozy place. This is my 2nd generation Yogurtron, which I made specifically for this job. It is a carefully crafted foam box that holds the temperature loss to 3 degrees overnight. But the yogurt doesn't care. 

You can use a cooler with foam peanuts or bubble wrap or whatever. Just don't use towels or they will smell a lot like yogurt. Which isn't as delightful as you might think. There is no need for a heater or worries about electrical failure. If your home is cold, build a nice thick foam box and preheat it with hot water.

I usually let the batch ferment overnight. Sometimes 6 hours if I'm in a hurry. Sometimes I forgot it for a whole day. The yogurt doesn't care. 

Step 5: Strain the Yogurt

Now you should have a fairly solid jug of yogurt. And that may be all you need. Screw on an un-pierced cap, refrigerate, and serve directly from the jug.

I like thick yogurt, so I developed this strainer. It is made from a pair of gallon-sized food containers. Since they nest, only 1 cover is needed. I drilled about 50 1/8th inch holes in the bottom of the top container. You could do just as well by gouging out a dozen rough holes with a knife. The yogurt doesn't care. 

I cover the holes with 2 coffee filters. The top container is set into the bottom container. Then I pour in the yogurt. But not quite all of it. 

I put the lid on and leave the strainer on the counter for an hour or so to drain. Why shock my fridge when I can just pour off warm whey? 

The strainer is showing no signs of wear from 16 months of constant use. 

Step 6: Store and Serve

I slide the entire strainer assembly into the fridge. It keeps draining as I use the yogurt, so there are never any nasty puddles of whey. I hate those. And since I've gone this far without washing much of anything, why start now? 

But there is one thing: I want to save some of each batch to inoculate the next. So the last few ounces out of the jug go into a jar. I leave this starter untouched for the week in the fridge.

Step 7: But Wait … There's More!

Now I have this valuable empty jug, so I give it a rinse. With the top cut off, it makes a handy container for edible garbage. Then my main garbage doesn't get stinky, so I can really pack those bags for weeks. One jug — three uses.

Step 8: The Circle of Life

I was thinking about these clever bacteria: They have evolved to trick us into using our bodies to promote their culture. So exactly who is the "superior" species?

This is a robust process. Over the past 2 years I have fermented about 80 gallons of yogurt. I've used different gear and different milk and made every mistake. For the past 60 batches, I have used only my own starter. Still *never* a failure. I am careful about sanitation; brush cleaning everything with a little bleach in my dish detergent. But my kitchen isn't a laboratory. This bacteria is so territorial, it's fighting off other microorganisms. It creates it's own environment for its safety and our delight. After 60 generations, it's growing like fresh culture.

I tried some batches with added dry milk. That's just more trouble and expense. Fluid milk is cheaper than the equivalent powdered milk. If I need more yogurt for a special culinary project, I'll buy a 2nd jug.

After losing a lot of weight and radically improving my health, I have switched from skim to whole milk. The resulting yogurt product is luscious. Like cream cheese (but with flavor), you can spread it on toast. Of course I use it for fruit smoothies every morning. With a dab of olive oil and spices, it makes wonderfully thick and creamy salad dressings. When loaded with Southwest spices or wasabi, it sauces sandwich meat. Creamy belly-filling vegetable soups too.

With foamed cream or pasteurized egg white, it makes a sweet whipped pie filling. Oh yes. I hope to spend years discovering new yogurt desserts. And living well.

Cheers from Sarasota.



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    209 Discussions

    omg, you come from MY HOMELAND area, Sarasota. I am from Ft.Myers area. BTW, I would GIVE to be able to do this! Ho-made food is &*% good!! I die a lot whenn I taste ho-made food! Soo obscenely GOOOOOOD!

    Hi...Question is...I have made this by pouring into a stockpot and doing same temp etc..But in gal jug is definitely new...IN YOUR PIC...Your yogurt pouring out looks like cottage cheese..Will it smooth out? I assume it's because it's hard to blend/stir when you add the starter inside the jug..Can't mix well? But I definitely want a smooth creamy yogurt...Please let me know when you smooth it out?

    Also - I wouldn't worry so much about getting the accurate temperatures correct. I usually just boil my milk, and literally touch the side of the container to see if its warm enough. As long as it feels like hot latte you would get from a coffee store you are fine. In the event you wake up in the morning and your yogurt didn't ferment, turn on the oven to warm for like 7 minutes and turn off. Your yogurt will be ready within a hour!! :)

    I was reading your recipe of Yogurt and thought to share my method as well. I have been making yogurt daily for the past 10 years. I am worried that you are warming up the milk in the plastic jug itself. I don't believe that it is meant for it to be warmed up. You are adding unnecessary toxins into the milk. There is a lot of research about plastic containers (even BPA free) and links to cancer. It is very important that you do not warm anything in plastic.

    My recommendation would be to take a gallon of milk and pour it into a stainless steel pot. Warm it up to the desired temperature, let it cool down, add the starter, mix well, cover with lid and place in the oven (turned off). To prevent the milk from sticking to the pan - you can stir occasionally or keep it on a low setting. If it is winter time, you can throw a towel over it. The yogurt should be ready in 6-7 hours. If is not needed to strain as it will turn very chunky (unless you want greek yogurt).

    This is a really simple method- and you don't have to worry about making a hole in the jug or cooling it down in water. Seems very tedious.

    I usually make yogurt in the morning around 6am when I wake up. As I am making moring tea/breakfast, I will boil up a cup of milk, cool it down, add the yogurt, mix and place it in the oven. By 12-1 I have yogurt that is very fresh. It is not sour and naturally sweet. If you are in a rush you can also microwave the milk.

    Hope you like my post!!


    1 year ago

    A variation of the 1 gallon method

    I have made yogurt using an instant read thermometer through the cap of plastic gallon of whole pasteurized milk. I make Greek style yogurt by filtering through a colander lined with a large commercial paper coffee filter. I discard the whey and transfer the yogurt to a plastic container. It takes me several weeks to use it up.

    Recently I have greatly simplified the procedure with good results. Since the milk is pasteurized and in in an unopened container before I use it I heat it only to about 110 F. I do this by immersing it in a sink-full of hot water. The water supply from the faucet is about 140F. Letting it sit for about 1 hour brings the milk to temperature. I add the culture then incubate it in the gallon container by wrapping it in an ordinary automatic heating pad set at low with a towel wrapped around the whole assembly. I usually incubate it 10-12 hours.


    2 years ago

    I've made many a batch of your Yogurt by the Gallon, and love it! I haven't read all the comments, so I don't know if anyone else has discovered, as I did, a great way to strain the yogurt after making it. I have a rice steamer that I bought for a few bucks at a thrift shop, the kind that has two plastic containers that fit onto a base. The larger, outer container has perforations at the bottom of it (for letting in and holding steam around the smaller bowl in which the rice cooks). The one that I have holds the gallon of yogurt with a little room left over.

    I place the large perforated container into a glass bowl that happens to hold the container a couple of inches off the bottom. I wet a coffee filter and place it flat into the perforated container -- the filter exactly covers the perforated area. I pour the yogurt in, then set the whole set-up into the fridge to drain. Sometimes I leave it in this set-up until all the yogurt is eaten; if the yogurt gets too thick, I just stir some of the whey back in. Or else I'll turn the thickened yogurt into another bowl, trying to make it kind of flop in upside down, as the coffee filter will peel right off the bottom of the thickened yogurt.

    It might take a little bit of comparison shopping to find a bowl that fits nicely with the plastic rice cooker container, but this process does work great! The bowl that I use is an old Anchor Hocking glass bowl that I bought ages ago, and I don't know if that same kind is still available. There is 4 quart Anchor Hocking mixing bowl on Amazon that looks very similar.

    Another couple of hints -- if you have an electric kettle, boil water in it to add to the pan that you heat the yogurt in. It heats more quickly and saves energy over heating the water on the stove top. I also pour the still-warm water into the cooler that I use to incubate the yogurt (I like to have the water at 105 degrees, but it's probably not a big deal, as long as the water's not too hot) in order to keep the temp steady for longer.

    1 reply

    I often find myself boosting the warmup with an electric kettle too; especially when cooking on my honey's glass top range.

    Always good to hear about successful variations. Pictures of your rig would surely be useful to our fellow milk fermentors.

    Ive been using your method for atleast two years now. i thought i would finally post instead of just trolling back whenever i needed to check the reference temperatures. Thanks a gallon! Great yogurt! Easiest method out there! Excited to try the whey next time as my inoculant!

    1 reply

    Very nice of you to leave the kind words. Makes the world go round.

    I haven't perfected a compact 1 gallon straining method yet. I just wanted to comment about uses for the strained whey. A quarter cup of strained whey will ferment another batch of gallon yogurt. I save it to marinade meats. Soak oatmeal in it. Use it instead of water for baking bread. Dog likes it too! I use my crockpot bowl to heat a gallon in my microwave, on high, for 23 minutes. Gets it to 185 every time, I don't even check it any more. I don't know if it hurts my refrigerator, it still works- I put the hot milk in the frige for 1 hour. Once the milk is in the frige, preheat oven to 250f then turn it off, I have a pizza stone in the oven it may or may not absorb much heat. Take a quarter cup of whey from the frige and set out on counter. After 1 hour to cool off, add the 1/4 cup whey, cover and stick it in the oven.

    3 replies

    Thanks for a great comment.

    The nesting food containers continue to work well for me, but some people object to plastic contact. You could try drilling a 4 quart stainless steel bowl.

    Yes it is very convenient to get reliable timings for your method. But that is always peculiar to our gear and kitchen and ambient temps.

    I like your idea of using whey as the inoculant. I used this on a double batch this week and it worked perfectly. Also much more convenient to pour than yogurt. This is a solid improvement in the method. Collaboration is wonderful.

    Very intrigued by this tip! Just 1/4 cup whey per gallon?

    It doesn't just work; it is the best way.

    This is still my favorite Instructable of all time! I use this method twice a month and it has saved me so much time and dirty dishes. Thanks to a tip on another of your Instructables, I finally over came the hurdle of keeping the gallon warm overnight. I was at my pharmacy when they got a delivery of
    refrigerated drugs and they happily gave me the cooler that they came
    in. It's perfect! The dense foam is about 5 inches thick. I just had to cut out a couple of ridges and my gallon fits nicely inside. My yogurt was still warm 12 hours later. The reusable
    ice packs are a very nice bonus too! I'd like to encourage anyone looking for a great insulated container to check at your pharmacy. They even had more in the back that they asked if I wanted too.

    2 replies

    Very gracious to let me know of your success. Five inches, you say? Impressive.

    I looked at it tonight while waiting for my milk to cool. It looks like I exaggerated in my excitement on my find. It really seems to be about 3 inches thick. Dense though.

    Awesome work! I only make things in big batches, so this is perfect for me and I can't wait to try it! Here's a quick thought/suggestion for those of you like myself who love to cook, but HATE doing dishes (I always look for the method that allows me to wash the least number of dishes possible). Instead of actually using a pot to boil the water, fill up the sink and use a Large Volume Hot Water Coil Heater (if they don't allow the link below just enter the capitalized words into the search box over at amazon; I haven't bought one this size yet but for only $13 it's worth a try and the little ones work amazing!). Since you aren't actually making soup or pasta, or any other food directly in the water, why have to wash a pot? You might be able to just drain and dry a pot used for something like this, but I don't think I could sleep if I ever did that. I'm neurotic, I'd have to wash it properly. You might use this method for other things requiring a hot water bath as well (candle-making, cheesecake baking, or anything requiring a double boiler).


    Large Volume Hot Water Coil Heater

    Great "ible". I'm collecting the supplies & equipment. I was reading labels on yogurt @ market; would "pasteurized milk, contains live cultures" be a good starter for my first attempt at home culturing yogurt?

    1 reply

    Yes, that's perfect. Get the milk to target temps of 180F and 110F as carefully as you can, and the yogurt will take care of itself.

    this is an easy an cool setting the only thing that worries me is warming up milk in the plastic bin, the chance of chemicals released in to the milk from the hot plastic..