in June of 2017, I did not expect that it would become SO popular! One reason it is so popular is that it is very EASY to make. Another reason is that it TASTES so good!
I also did not anticipate all the questions that this method would bring, and putting all these questions/answers on my original Cold Start™yogurt post made it into a very long post.
, then come back and see if you have any questions.
where you will find the original recipe, & complete information about Cold Start™yogurt. Enjoy!
and it is simply using 2 ingredients: cold ultra pasteurized milk & a couple tablespoons of yogurt (also called starter), mixed together and letting the Instant Pot warm up your milk automatically to the perfect temperature. No heating or cooling your milk, and no additional or special equipment is necessary. "No Boil" is not accurate to describe this method, as milk is not boiled to make yogurt.
, milk is heated to 160°-180°F using the "Boil" setting of the Instant Pot to make yogurt. Milk is then cooled to 100°F -110°F, starter is added, and incubated. Incubate means keeping the milk warm, at a constant temperature of 100°F-110°F.
You can still make yogurt; it will require a couple of extra steps to heat the milk and find a method to maintain the temperature of your milk in the 100°F-110°F range for at least 8-10 hours. An accurate thermometer is needed. You can find
milks with this method. Shelf stable milks include: canned, boxed or powder milks. UHT (Ultra high temp) milks are the same as ultra pasteurized milks.
Pasteurized milk is heated to 160°F, kills any harmful bacteria, but still has natural bacteria in the milk. This natural bacteria competes with the yogurt bacteria while the milk is warming up to incubation temperature. Results are thin yogurt that doesn't have very many yogurt cultures.
Ultra pasteurized milks are heated to 280°F, quickly cooled and are 99.9% bacteria free. While the milks are warming up to incubation temp,
the yogurt bacteria is allowed to grow, resulting in yogurt! If you want to use any other milks to make yogurt, use the more
Carnation Instant Milk Powder
Easily available and tastes great. Use it alone or in addition to milk to make a thicker yogurt. 1/3-1/2 cup of instant powdered milk added to 8 cups of cold milk will help make your yogurt thicker.
Not everyone has access to fresh milk, so dry, or powdered milks are perfect for the cold start method and you can make a concentrated milk by using half the amount of water that the recipe calls for. You can also add instant powdered milks to cold milk to help thicken your yogurt.
You may live in another country where fresh milk is not available. You may see Ultra Pasteurized, Ultra High Temp, High Temp Short Time (HTST) or Extended Shelf Life (ESL) on the package.

Amanda Atchley, who lives in Japan, found this ESL milk. It took about 11 hours to set, which can be true of some ultra pasteurized milks. She also strained it for a thicker texture.
Here are some examples of boxed, shelf stable milks. Some people have found boxed milks at their local dollar store.
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I live in Canada. What milks can I use?
You can use any UHT (ultra high temp) milk with the Cold Start. Most organic or lactose free milks are UHT. Organic milks can take longer to culture or set, as long as 10-12 hours.
Natrel filtered milks are NOT ultra pasteurized. Only the lactose free version is ultra pasteurized, so look for the orange label.
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Do I need to use Sweetened Condensed milk?
No. You only need to use milk & a couple of tablespoons to make yogurt. Adding sweetened condensed milk is optional and is added along with the milk at the beginning. It adds sweetness, and thickens the yogurt.
You can choose
ONE of the following, add it to your milk to flavor and sweeten your yogurt:
The higher the protein, the thicker the yogurt. Adding protein drinks, or "shakes" can thicken yogurt without using full fat or adding instant powdered milks. Adding 1-2 of these 11oz shakes to a fat free milk can help make a very thick yogurt while adding flavor and keeping the sugar very low.
Can I use this method with other Ultra Pasteurized milks?
For the most part, yes. Sometimes the high heat process damages the proteins in the milk to the point that it won't set. Some UP milks take longer to incubate, up to 10 hours or more. Milks that you can try for the cold start method are: Organic milks, Soy milk, canned milks (evaporated or sweetened condensed), heavy cream, half & half, powdered milk (mixed with filtered water), any ultra pasteurized or ultra high temp milks. Organic milks can take longer to culture or set, as long as 10-12 hours.
You will need to keep in mind that Fairlife milk has more protein, which helps make a thicker yogurt. Higher fat and more protein is what makes whole milk yogurt thicker than a1% or non fat milk yogurt.
Why is milk heated to make yogurt?
Three reasons:
1.
Kill pathogenic (harmful) bacteria. If raw milk is used, heating it kills bacteria. The higher you heat the milk, the more bacteria is killed. Heating milk to 160°F is pasteurization.
2.
Allow only yogurt bacteria to grow. Yogurt bacteria begin to grow in a 100°F-110°F environment. So milk is heated to at least this temperature to allow the yogurt bacteria to begin doing their work.
3.
Change proteins. The proteins in the milk begin to change, or denature, when the milk is heated. The higher the temperature of your milk, the more the proteins will denature. This process results in a thicker, more custard-like yogurt.
Ultra pasteurized milks have already been heated to 280°F, so no pre-heating is necessary.
Can I heat my regular pasteurized milk and Cold Start it later?
No. You would have to heat your milk to at least 280°F, which can foam, scorch and burn. Heating it only to 180°F would not be enough to use it for Cold Start yogurt, for the reasons listed above. You can read more about ultra pasteurization in the next question.
Are Ultra Filtered & Ultra Pasteurized the same thing?
No. Ultra filtered milks are milks that are screened, or filtered, to separate the milk components of water, fat, sugar, lactose, etc. and are put back together. Low fat milks use a similar process. Ultra filtered milks need to use the traditional boil method and cannot use the Cold Start.
Ultra pasteurized milks are heated to 280°F, quickly cooled and are 99.9% bacteria free. These milks are suitable for the Cold Start method because they are heated for a thicker yogurt and are bacteria free.
Do I have to use Fairlife Milk?
No. You can use any ultra pasteurized, ultra high temp (UHT), or shelf stable milks which include: canned, boxed or powdered milks. Many use Fairlife milk as it helps make a much thicker yogurt that doesn't need straining. This is because it has more protein than other ultra pasteurized milks.
What is Fairlife milk?
It is 100% dairy milk that filtered, using a process similar to water filteration, by using sieves,
adsorption, ion exchanges and other processes, resulting in a milk that has 50% less sugar, 50% more protein, 30% more calcium and is labeled as lactose free.
Fairlife milk comes from
Fair Oaks Farms in Indiana. Coca Cola does not own Fairlife; it has a partnership with Fair Oaks Farms, handling the marketing and distribution. You can find a
list of 74+ stores that carry Fairlife here.
Is Fairlife milk Ultra Pasteurized?
Yes, Fairlife milk is ultra pasteurized.
It doesn't say it on the carton, so I contacted Fairlife, and this is the response I received:
Can I use any Lactose free milk? How does lactose work?
Yes. Most lactose free milks are ultra pasteurized and work well.
Fairlife milk is lactose free. Lactase is added to the milk to make it "lactose free.":
"Those who are lactose intolerant are not allergic to milk, or even to lactose. Instead, they lack the digestive enzyme needed to break down the lactose, or the sugar in milk.
"Lactose-free milks are the same as regular milk, except for the addition of lactase. This neutralizes the lactose and, therefore, eliminates the gastrointestinal trauma. Lactase does make milk taste sweeter. Also, to neutralize the lactase enzyme inactive, manufacturers ultra-pasteurize the milk, a move that extends the shelf life." -
Karen Fernau, Food writer
Here is another explanation of lactose free milk:
"It’s neither practical nor really possible to remove lactose from milk — not only would it be logistically difficult, it’s simply not necessary. Instead, manufacturers react the lactose chemically, altering its composition and converting it into molecules that your digestive system processes easily. To react lactose, manufacturers add small amounts of the enzyme lactase to milk, explains OrganicMeadow.com, a producer of lactose-free milk. The lactase splits lactose into its constituent components, which are two sugars called glucose and galactose." - How is Lactose Free Milk Made?
But wait...don't you need lactose to make yogurt?
There are two things at work when making yogurt with lactose free milk. First, the lactose free milk is treated with the lactase enzyme to break down the lactose into its component molecules, glucose and galactose, which make it easier for the bacteria to ferment. Otherwise, they do this conversion themselves, but the process is a bit slower.
Second, the ultra filtered milk is higher in protein, and the action of the bacterial fermentation creating lactic acid which then acts to coagulate the protein. More protein, easier coagulation. -
Kathy Peschell
Do I have to use a non-dairy yogurt with Lactose Free milk?
No. You can still use a dairy yogurt as your starter! The lactase added to lactose free milks will help you digest any lactose that is found in your starter. If you want to use a dairy free yogurt as your starter, you can use a dairy free yogurt:
Silk,
SoDelicious, or try
Yogurmet, a freeze dried powdered starter.
Can I use Low Fat milk?
Yes, you can use low fat or skim milk for for making yogurt with the cold start method.
Lower fat milks have a higher water content and may yield a more soft-set, pudding like yogurt. If you want a thicker yogurt,
you may want to strain or add
non-fat instant powdered milk your yogurt for a thicker consistency. Fairlife, Joyya and similar low fat & skim milks have more protein, which help contribute to a much thicker yogurt than other milks.
It is not necessary to use a
low fat yogurt starter with these milks - you only want the starter for the live cultures. You can find out more about
How to Choose a Starter, here.
Can I use Chocolate milk or a flavored milk?
Fairlife Chocolate milk, like any store bought chocolate milk, has too many additives (thickeners, sugars and other ingredients) that interfere with the culturing process. Most people using Fairlife and other chocolate milks get a thin, "pudding-like" texture, even with a 9 -10 hour culturing time. Some add
sweetened condensed milk, which does help thicken a little bit, but adds sugar to an already sweet milk. The additional sugars in the milk will need at least a 10 hour culturing time, which makes a tangy or tart yogurt. For most people, this combination of chocolate + tartness is not a pleasant taste. If you want a chocolate yogurt, make a plain yogurt, and after chilling, add chocolate syrup, chocolate drink mix powder, whey protein powder or a small box of instant pudding mix.
How can I make a DAIRY FREE cold start yogurt?
If you need a dairy free option, Soy or Ripple (pea) milk work great!
TIP: Soy or pea milks need at least 12 hours incubation to thicken and will continue to thicken or "set" while chilling in the fridge. It will not be a thick Greek style yogurt, but more of a traditional yogurt consistency.
These are the only plant based milks that don't need a thickener. Ripple pea or Soy shelf stable milk (must only contain soy and water).
Almond, Coconut, Rice and other plant based milks need a thickening agent (gelatin, agar agar, tapioca starch, etc) and those thickeners require heat to activate. These milks will not work well for the cold start method.
Does the Cold Start™ method save any time?
Yes, it can! It only takes 2-3 minutes to mix up your milks, push the yogurt incubation setting, and walk away. Most find that they don't need to strain, which saves 4-8 hours.
Is it safe to make yogurt with this method?
Yes. I have tested the temperatures of the milk in my testing and found that the Instant Pot yogurt setting warms up the milk to 107°F within 30 minutes, well within food safety guidelines. The Unsafe Food Zone temperature range is 40°F-140°F
as determined by the USDA.
The Unsafe Food Zone
The unsafe food zone is any food that is left out in the temp range of 40°F-140°F for 2 hours or more. It is perfectly fine for any milk to be in the unsafe food zone
as long as the yogurt starter is actively working in the milk. Once the yogurt starter is active (in the 100°-110° range), it begins to produce acidic whey, which continues to ferment and preserve your milk in this temp range. Milk without an active yogurt bacteria present should not be left out at room temperature for 2 hours or more.
UP/UHT (ultra pasteurized/ultra high temp) milk already has
99.9% of the bacteria killed during processing, meaning there is little risk, if any, of any pathogenic (bad) bacteria multiplying during the warming up to the incubation zone, as long as it is less than 2 hours. Once you open UP/UHT (ultra pasteurized/ultra high temp) milks, it needs to be treated like dairy milk. Even though UP/UHT milks are shelf stable in their sterile packaging for 6+ months, once opened, their fridge shelf life is 1-2 weeks and should not be left open at room temperature for more than 2 hours.
You should not try the Cold Start™ method with raw or regular pasteurized milk. See below.
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If you are undecided about the safety of using the Cold Start™ method, you can always warm up your yogurt to 100°-110°F, add your starter and incubate from there.
Can I use the Cold Start™ method with regular pasteurized milk?
I do not recommend using the Cold Start™ method with regular pasteurized milk. Even though the milk is heated to 160°F for pasteurization,
there are still natural bacteria present in the milk. This bacteria can grow/multiply during the 30-40 minutes of warming up to incubation temp & compete with the natural bacteria in the yogurt starter. This competition of bacterial strains may result in either a thin, runny yogurt, lumpy, bitter, stringy or ropey yogurt. You can see the results of what happened with raw milk:
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Raw milk used with the Cold Start™ method |
For raw, pasteurized & filtered milks,
you can find this simple method here for thick, Greek style yogurt.
How do I sweeten or flavor the yogurt and when do I add it?
If you want a vanilla yogurt, you can add your vanilla extract when your yogurt has chilled and strained. It is theorized that the alcohol from the extract can interfere with the culturing process, but you can add vanilla bean paste or scrape a 2"vanilla bean into your milk
before starting. If you are straining your yogurt, any flavor or sweetener can go out with the whey.
Sweetener, Added AFTER CHILLING:
You can use any sweetener of your choice after your yogurt has chilled and strained. Granulated sugar, powder sugar, maple syrup, or any alternative sweetener can be used. Honey mixes in better if it is warmed first. If you add sugars to your milk prior to heating, it can inhibit, or slow down the culturing process, adding time to your yogurt to properly set. I prefer to add sweetener after my yogurt has finished. You can add a small box of instant pudding, coffee, drink mix, or get some inspiration from this
topic in my Instant Pot Yogurt Guide for Newbies.
Sweetened Condensed Milk, Protein Drinks, Creamers, Added to the milk BEFORE incubating:
You can add a up to small can of sweetened condensed milk to your Fairlife milk prior to heating. Make sure it is mixed in well and plan to add time if necessary to allow your yogurt to gel, or set. This makes a creamy, slightly sweet vanilla yogurt.
Can I mix the milk & starter together and pour them into individual jars first?
If you are not straining your yogurt and like the consistency, you can try it. Fairlife and other filtered milks will make a yogurt that has the thickness between Greek and traditional yogurts. You can use canning jars or Oui yogurt jars.
Dry fit your jars to make sure they fit. Estimate the amount of milk you will need to use. If you have any milk mixture left over, put it in a clean container with well fitting lid and use it within 24 hours to make yogurt.
When 2 layers of jars are used, the
bottom jars will set while the top layer is still liquid milk. It can take
at least 10 hours to for the top layer to set. No trivet/metal rack or lids are necessary. You can add 1"-2" of water, which seem to help incubate the yogurt, but it is not required.
Does the texture change with this method?
No. If you use whole milk, it will taste creamier. You can use 2% or skim, and have it strained nice and thick, but the texture may not be as creamy. If you like the taste of the milk, you'll enjoy the yogurt made with it.
Why is my yogurt grainy or gritty?
The yogurt stuck on the bottom of the pot does have a gritty or grainy texture. Take a look at the photo, below, taken right after incubation and before straining in the fridge. Avoid scraping this into your yogurt. This may be difficult to avoid if you chill your yogurt while in the pot prior to straining.
Try slowly pouring your yogurt immediately into another bowl or your lined strainer and chill in the fridge or use the
Ice Cube tip in my traditional yogurt recipe, which keeps the milk from sticking to the bottom of the pot. If you still find your yogurt to have a grainy texture, try another brand of yogurt as your starter. Each brand of yogurt has a unique blend of bacterial strains that make up both the tang & texture of your yogurt.
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The yogurt stuck to the bottom of the pot had a grainy, gritty texture. When using the ice cubes, this is how my pot looked after milk was heated.
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