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Fermented milk from France, Germany, Scandinavia, Netherlands
Cultured (lactic) butterbeurre de baratte
Cream, or in many countries whole soured milk, is soured by lactic bacteria and then churned until butter grains separate from the buttermilk. Dairies pasteurise the cream, add a culture and hold it through a set temperature programme for 12–15 hours before churning. Made in 4 steps over 12 h – 15 h. The longest step, sour and ripen the cream with a culture, takes 12–15 h (Tetra Pak) and runs at 6–21 °C (Tetra Pak). Lactococcus lactis subsp. lactis, subsp. cremoris and subsp. diacetylactis does most of the fermenting.
No fixed amounts recordedNo fixed batch; dairies set the ripening programme by the iodine value of the milk fat, and households churn whatever soured milk or cream they have collected.
Lactic culture (dairies), or the milk's own bacteria (households) · Lactococcus lactis subsp. lactis, cremoris and diacetylactis are the usual cultures[lei2025][fao-tmp-iii]
Salt (optional) · Butter may be unsalted, salted or extra-salted[tp-butter]
Starter: defined culture (dairies); spontaneous souring (traditional)
Total time across the recorded steps: 12 h – 15 h
Start
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What changes:The cream is heated to kill unwanted microbes before the culture goes in
Step 1 of 4
Pasteurise the cream
Time
Not documented
Temperature
85 °C
Reported
Salt
None given
Acidity
Not documented
Which microbes the steps name, step by step
Lactococcus lactis
Traditional butter skips this step and uses raw milk or cream soured overnight. Output: pasteurised cream.
Flavour
Not documented
Texture
Not documented
Colour
Not documented
Microbes at work in this step
Not documented for this step.
Method
Measured measured in a studySet fixed by a specification or tested recipeReported one source reports itTypical a general value, not sourced for this fermentUnconfirmed not yet checked against a source
What makes this one different
Cultured butter is churned from cream or milk that lactic bacteria have soured first, while sweet-cream butter is churned from fresh cream. In the NIZO method dairies churn sweet cream and add culture and lactic acid to the butter afterwards.
NIZO methodSweet-cream butter grains are mixed with an aromatic starter and a lactic-acid permeate made by Lactobacillus helveticus.
Makkhan (South Asia)Whole dahi churned in a wooden piston churn; the buttermilk is chaas, and makkhan is often boiled into ghee.
Gibde (Chad)Unwashed butter shaken from sour milk in a gourd for 1–2 hours; keeps 21–30 days.
Afar shoulder churnSour milk in a skin bag slung over the shoulder and pushed with the elbow while walking.
Safety
Dairies pasteurise the cream at 85 °C or more before adding the culture. Traditional butter from raw soured milk is not heated; FAO notes that it is often made from milk of poor quality that has curdled before the cream could rise.
FAO suggests butter began when nomads carrying sour milk found that hours of shaking on an animal's back split it into two phases. Churning soured milk is still the most widespread traditional method in the developing world.