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Cultured butter
Level 2 · some practice
Cream cultured for a day, ripened cold overnight and churned until it splits into butter and buttermilk. You get both.
- Time
- 16–20h
- Temperature
- 68–77°F
- Jar
- 1L
The golden rule: pasteurized cream or milk, a bought culture, and into the fridge as soon as it thickens.
No sign-up. We guide you step by step, from the scale to the fridge.
Reviewed October 26, 2026 · 40 facts, each with its source
Before you start
Cultured butter is made from fermented cream. Well into the 19th century, butter was made from cream left to sour on its own, but that was touchy and outside microbes often spoiled it. Today the cream is cultured with a commercial mesophilic culture, like crème fraîche, and then churned until it splits into butter and cultured buttermilk. The cream follows the British Columbia food safety sheet for professional kitchens, and the churning, the University of Guelph's dairy science textbook. You'll need a thermometer.
You'll need
- 1-liter (quart) glass jar with a lid
- Pot for a water bath
- Kitchen thermometer
- Electric mixer with whisk beaters
- Large bowl
- Strainer
- Cheesecloth
- Spatula or wooden spoon
- Bottle or jar with a lid for the buttermilk
- Kitchen scale, if you're salting it
Step by step
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Bring the cream to 68–77 °F in a water bath
Wash the jar, lid, bowl, strainer, beaters and spatula in hot soapy water and rinse them well. Pour the cream into the jar and set it in a pot of lukewarm water. Stir until the cream reaches 68–77 °F, or the temperature on the culture packet. It should get there within 1 hour.
Tip: Read the cream label closely: over 33% fat, pasteurized, not UHT and with no stabilizers such as carrageenan. With UHT cream or stabilizers it won't thicken.
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Add the culture and stir gently
Sprinkle the culture over the cream, using the maker's dose for 1 liter, and stir gently until it's spread through.
Tip: Always use a commercial culture. The British Columbia sheets don't approve a previous batch as a starter, and that includes the buttermilk from this recipe.
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Leave it covered at 68–77 °F for 16 to 20 hours
Close the jar and leave it at 68–77 °F, away from drafts and without moving it. It's ready when it has thickened and smells tangy. If you have a pH meter, it should read 4.6 or below.
If it hasn't thickened by 22 hours, throw it out. That's a house rule: the British Columbia sheets discard a batch that hasn't reached pH 4.6 two hours past the expected time, and we apply that to the texture.
If your kitchen is between 77 and 86 °F, it goes faster: the British Columbia sheets give up to 12 hours at about 84 °F. Check it from 8 hours on and, if it hasn't thickened by 14, throw it out. Above 86 °F, find it a cooler spot. Both are house rules.
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Chill it and let it ripen in the fridge for 12 to 15 hours
Put the jar in the fridge as soon as it's ready. It should drop to 68 °F within 2 hours and to 39 °F within 4 more: 6 hours in all, at most. If the fridge is full, chill it first in a sink of cold water or ice. Leave it in the fridge for 12 to 15 hours: in the cold, the fat crystallizes and churns better later.
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Churn it at 45–55 °F until it splits
Take the cream out of the fridge and check it: it should be between 45 and 55 °F. Guelph churns at 45–50 °F in summer and 50–55 °F in winter. If it's colder, leave it out for a while. Pour it into the bowl and beat it with the mixer on medium. First it whips like whipped cream. Keep going: the foam breaks and yellow grains of butter appear in a thin, white liquid.
Tip: When it starts to break, turn the speed down and cover the bowl with a towel: the buttermilk splashes.
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Strain the butter and keep the buttermilk
Line the strainer with the cheesecloth, set it over another bowl and tip in the butter. The liquid that drains out is cultured buttermilk. Pour it into the bottle, close it and keep it in the fridge, at 39 °F or colder. Use it within 3 days and throw out the rest.
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Wash it in ice-cold water and work it
Put the butter in the clean bowl with some of the ice-cold water and work it with the spatula, pressing it against the sides. Pour off the cloudy water and repeat with fresh water until it runs almost clear. Then work it without water and pour off what it releases, until no droplets show.
Tip: Washing removes the buttermilk left inside. The industry rarely washes butter now; at home we wash it to leave as little buttermilk in it as possible. That's a house rule.
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Salt it if you like, wrap it and keep it cold
If you want it salted, weigh it and sprinkle on 10 to 30 g of fine salt per kilo (2.2 lb) of butter, 1 to 3%. Work it well to spread the salt: salt improves the flavor and helps it keep. Wrap it or pack it in a jar, and keep it in the fridge. Use it within a week and freeze what you won't use in that time.
Tip: The week is a house rule. For store-bought butter, once opened, Oregon State University Extension gives a couple of weeks; homemade butter holds more buttermilk, so we count half.
No sign-up. We guide you step by step, from the scale to the fridge.
Variations
The same method, a different flavor. Once you have this one down, try one of these.
How to tell it's going well
- Pasteurized cream only. The cream spends hours at room temperature before there's any acid.
- Use a commercial culture, at the maker's dose. A previous batch, or its buttermilk, isn't a starter.
- If it hasn't thickened by 22 hours, throw it out, or by 14 if the kitchen is at 77–86 °F. With a pH meter: if it hasn't reached 4.6 by then, too.
- Into the fridge right away: down to 39 °F within 6 hours.
- The buttermilk, 3 days in the fridge at most.
- The butter, a week in the fridge, and the rest in the freezer.
- If it smells rancid or changes color, the butter has gone rancid: it tastes bad. If mold appears, throw it out. Bacteria you can't see may grow with the mold. Don't sniff it.
Where every number comes from
Every number in this recipe comes from a food safety guide. We keep a copy of each source and quote its exact words.
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1
Well into the 19th century, butter was made from cream left to sour on its own
“Well into the 19th century butter was still made from cream that had been allowed to stand and sour naturally.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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2
Souring on its own was touchy, and outside microbes often spoiled it
“The natural souring process is, however, a very sensitive one and infection by foreign micro-organisms often spoiled the result.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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3
Cultured butter uses mixed mesophilic cultures
“If ripening is desired for the production of cultured butter, mixed cultures of S. cremoris, S. lactis diacetyl lactis, Leuconostocs, are used”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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4
Traditional batch churning uses cream with 25 to 35% fat
“traditional batch churning from 25- 35% mf. cream”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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5
The cream ripens cold for 12 to 15 hours before churning
“As a rule, aging takes 12 – 15 hours.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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6
Churning gathers the fat into butter grains
“In the churning process the cream is violently agitated to break down the fat globules, causing the fat to coagulate into butter grains, while the fat content of the remaining liquid, the buttermilk, decreases.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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7
First it whips, then the foam breaks into butter and buttermilk
“If beating continues the fat clumps increase in size until they become too large and too few to enclose the air cells, hence air bubbles coalesce, the foam begins to “leak” and ultimately butter and butter milk remain.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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8
Churned at 45–50 °F in summer and 50–55 °F in winter
“7-10°C in summer and 10-13°C in winter”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
Show the remaining 32 claims
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9
Too warm and it turns greasy; too cold and it turns brittle
“If churning temperature is too warm or if the thermal cream aging cycle permits too much liquid fat, then a soft greasy texture results; if too cold or too much solid fat, then butter becomes too brittle.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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10
The cream splits into butter grains and buttermilk
“Thus the cream is split into two fractions: butter grains and buttermilk.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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11
Washing removes leftover buttermilk; the industry rarely does it now
“It used to be common practice to wash the butter after churning to remove any residual buttermilk and milk solids but this is rarely done today.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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12
Well worked, no water droplets show
“Water droplets decrease in size during working and should not be visible in properly worked butter.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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13
If salted, 1 to 3% salt
“If the butter is to be salted, salt (1-3%) is spread over its surface, in the case of batch production.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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14
Salt improves the flavor and helps it keep
“Salt is used to improve the flavour and the shelf-life, as it acts as a preservative.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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15
After salting, it's worked well to spread the salt
“After salting, the butter must be worked vigorously to ensure even distribution of the salt.”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Butter Manufacture · read on October 25, 2026
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16
Cream over 33% fat; it won't work with UHT cream or stabilizers
“Crème fraîche is made from high fat whipping cream (>33% BF). This recipe will not work with ultra-pasteurized (UHT) cream or cream that has added stabilizers.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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17
The cream is cultured just like crème fraîche
“The process for making Crème Fraîche is the same as buttermilk and sour cream. However, it is made with heavy cream /whipping cream.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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18
The British Columbia sheets are written for professional kitchens
“Production of Crème Fraîche in Food Service Establishment”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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19
Pasteurized dairy only
“Purchase and use only pasteurized dairy ingredients from approved sources.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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20
Commercial culture only
“Use only approved commercial starter culture.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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21
The dose and temperature are the maker's
“Follow the manufacturer’s instructions for usage rate and incubation requirements.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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22
A previous batch isn't approved as a starter
“Previous batches of crème fraîche are not approved for use as a bacterial culture.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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23
To the culturing temperature within 1 hour
“Heat cream to desired temperature as per your recipe (reach temperature within 1 hour)”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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24
In a water bath and stirring, so it doesn't scorch
“Stir constantly to avoid burning the cream. Use of a water bath or double boiler is recommended.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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25
Stir gently until the culture is spread through
“Mix gently and thoroughly to disperse the culture.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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26
Covered, at room temperature and away from drafts
“Crème fraîche may be incubated by leaving it covered at room temperature in an area away from drafts.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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27
pH 4.6 or below
“Endpoint pH <4.6 or lower within 2 hours of the expected incubation time.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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28
If it hasn't reached pH 4.6 two hours past the expected time, it's discarded
“If the end point pH (pH 4.6 or lower) has not been reached after 2 hours past the expected incubation time, there is a problem with the batch and it must be discarded.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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29
To 68 °F within 2 hours and to 39 °F within 4 more, 6 hours in all
“Cool down to 20°C within 2 hours, and 20°C to 4°C within 4 hours. Total cooling time not to exceed 6 hours.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Crème fraîche, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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30
Guelph, for buttermilk: 16 to 20 hours at 68–77 °F
“Milk is usually heated to 95°C and cooled to 20-25°C before the addition of the starter culture. Starter is added at 1-2% and the fermentation is allowed to proceed for 16-20 hours”
University of Guelph, Department of Food Science (Goff, Hill & Ferrer) · Dairy Science and Technology eBook: Cultured Dairy Products and Cheese · read on October 25, 2026
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31
British Columbia, for buttermilk: up to 12 hours at about 84 °F
“generally just around room temperature (29°C). This low temperature fermentation can take as long as 12 hours.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Buttermilk, production of dairy products in food service establishments · read on October 25, 2026
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32
To cool it, cold water or an ice bath
“Cool the pot in a sink with cold water or ice bath.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Buttermilk, production of dairy products in food service establishments · read on October 25, 2026
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33
The buttermilk, in the fridge at 39 °F or colder
“Store at 4°C or colder.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Buttermilk, production of dairy products in food service establishments · read on October 25, 2026
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34
The buttermilk is thrown out after 3 days
“Discard product after 3 days.”
Province of British Columbia (Ministry of Health, BCCDC Environmental Health Services, Fraser Health), Guidelines for the Production of Dairy Products in Food Establishments · Sample documentation: Buttermilk, production of dairy products in food service establishments · read on October 25, 2026
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35
Store-bought butter, once opened, a couple of weeks
“If the package was opened, stored in the door of the refrigerator, or left out for a period of time, then the storage time will be only a couple of weeks.”
Oregon State University Extension Service (Ask Extension) · Does butter expire? · read on October 25, 2026
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36
Butter you won't use soon goes in the freezer
“If you are not going to use the butter within a couple of weeks of purchasing it, the butter should be stored in the freezer.”
Oregon State University Extension Service (Ask Extension) · Does butter expire? · read on October 25, 2026
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37
Salted butter keeps longer
“Salted butter generally lasts longer.”
Oregon State University Extension Service (Ask Extension) · Does butter expire? · read on October 25, 2026
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38
Rancid butter changes color and tastes bad
“The butter you used may have been rancid, which would cause a change in the color of the butter and an unpleasant flavor.”
Oregon State University Extension Service (Ask Extension) · Does butter expire? · read on October 25, 2026
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39
Bacteria can grow along with mold
“Foods that are moldy may also have invisible bacteria growing along with the mold.”
USDA Food Safety and Inspection Service · Molds on Food: Are They Dangerous? · read on October 20, 2026
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40
Don't sniff mold
“Don't sniff the moldy item. This can cause respiratory trouble.”
USDA Food Safety and Inspection Service · Molds on Food: Are They Dangerous? · read on October 20, 2026
