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Sour cream
Level 2 · some practice
Light cream thickened with a culture that works at room temperature. It's heated, cooled fast, cultured for a day and gets better after another day in the fridge.
- Time
- 16–20h
- Temperature
- 68–77°F
- Jar
- 0.5L
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 · 31 facts, each with its source
Before you start
Sour cream is light cream cultured with a mesophilic culture, the kind that works at room temperature. It turns thick and tangy. No home guide gives figures for making it. This recipe follows the British Columbia food safety sheet for professional kitchens, and takes its time from the University of Guelph's dairy science textbook. You'll need a thermometer.
You'll need
- Pot for a water bath
- Whisk
- Kitchen thermometer
- 500 ml (pint) glass jar with a lid
- Clean spoon
Step by step
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Whisk the milk powder into the cream and heat it to 180 °F
Wash the pot, whisk, jar, lid and spoon in hot soapy water and rinse them well. Pour the cream into the pot, ideally in a water bath, and heat it gently. When it's warm, add the 6 g of milk powder a little at a time, whisking. Keep heating, stirring all the while, to 180 °F and hold it there for 10 minutes.
Tip: If you can't find 18% cream, mix equal parts heavy cream and whole milk: it comes out around 19%, inside the 14 to 20% the sheet asks for.
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Cool it to 68–77 °F within 1 hour
Set the pot in a sink of cold water or ice and stir until the cream drops to 68–77 °F, or the temperature on the culture packet. It should get there within 1 hour: if it takes longer, microbes that come with the milk can grow.
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Pour it into the jar, add the culture and stir
Pour the cream into the jar. Sprinkle the culture over it, using the maker's dose for 500 ml, and stir gently until it's spread through.
Tip: Always use a commercial culture. The British Columbia sheets don't approve a previous batch or store-bought sour cream as a starter.
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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 within 6 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.
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Let it rest a day and use it within 3 days
It's better if you let it rest a day in the fridge before using it. Keep it covered, at 39 °F or colder, and use it within 3 days of making it. Throw out the rest and don't freeze it. The 3 days are the British Columbia figure for professional kitchens; there's no published figure for home cooks, so we don't count on more.
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. Neither a previous batch nor store-bought sour cream is a starter.
- Cool it fast after heating: to 68–77 °F within 1 hour.
- 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.
- In the fridge for 3 days at most. Don't freeze it.
- If mold appears, throw it all out. In cream, mold can reach below the surface and bring bacteria with it. 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
The British Columbia sheets are written for professional kitchens
“Production of Sour Cream 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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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2
In Canada, pasteurized cream soured with a culture and at least 14% fat
“the product prepared by the souring of pasteurized cream with acid producing bacterial culture and shall contain not less than 14 percent milk fat.”
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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3
14 to 20% fat; an 18% cream works well
“Sour cream is a cultured cream product that contains between 14 and 20% butterfat. An 18% BF Table Cream can be a good starting point for this product.”
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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4
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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5
125 g of nonfat dry milk per 10 liters of 18% cream
“10 Litres of pasteurized 18% BF cream 125 g skim milk powder (about 2/3 cup)”
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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6
Milk powder improves the texture
“Skim milk powder can be added to improve the consistency.”
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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7
The milk powder goes slowly into the warm cream, with a whisk
“Slowly add dry ingredients to warm milk and cream portion of mix using a whisk.”
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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8
180 °F for 10 minutes, for a better texture and longer life
“It is beneficial to use a heat treatment such as 82 °C for 10 minutes. This optional heat treatment will denature the milk proteins and improve shelf life.”
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
Show the remaining 23 claims
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9
Heat and milk powder make it firmer and thicker
“Heat treatment and the addition of skim milk powder to increase total milk solids are significant factors with respect to firmness and viscosity of the resulting sour 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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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10
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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11
To the culturing temperature within 1 hour
“Cool down quickly to incubation temperature (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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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12
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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13
If it cools slowly, unwanted microbes can grow
“Prolonged cooling time may allow for the growth of undesirable microorganisms (for example, spore formers naturally present in the milk).”
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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14
The culture is mesophilic and grows at room temperature
“The starter culture used for sour cream is a mesophilic culture and grows at room temperature.”
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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15
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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16
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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17
Neither a previous batch nor store-bought sour cream is approved as a starter
“Previous batches of sour cream or sour cream from other manufacturers 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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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18
Covered, at room temperature and away from drafts
“Sour cream 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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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19
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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20
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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21
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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22
It's better after a day of rest
“The sour cream is better if allowed to age for one day before use.”
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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23
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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24
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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25
Don't freeze it
“Do not freeze”
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: Sour cream, production of dairy products in food service establishments (September 2022) · read on October 25, 2026
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26
Sour cream cultures like buttermilk
“Inoculation and fermentation conditions are also similar to those for cultured buttermilk, but the fermentation is stopped at an acidity of 0.6%.”
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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27
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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28
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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29
Moldy sour cream goes in the trash
“Yogurt and sour cream Discard Foods with high moisture content can be contaminated below the surface.”
USDA Food Safety and Inspection Service · Molds on Food: Are They Dangerous? · read on October 20, 2026
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30
Bacteria can grow along with mold
“Moldy foods may also have 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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31
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
