Ingredient
Yogurt culture
Also known as: Lactobacillus bulgaricus, Streptococcus thermophilus, yogurt starter
Mixed live culture of thermophilic lactic-acid bacteria — the right ingredient to convert milk into yogurt by acidification at 105–115°F over 4–12 hours. Two principal species: *Streptococcus thermophilus* (faster-acidifying, sweeter) and *Lactobacillus delbrueckii subsp. bulgaricus* (slower, more tart); they grow in symbiotic complement. Heirloom cultures (Bulgarian, Greek, Caspian Sea) are vegetatively reproducible — every batch yields enough live culture to start the next, indefinitely. Commercial freeze-dried starters are single-use to 7-batch-use depending on strain. The right ingredient as the foundational dairy ferment, the precursor to many cheese cultures, and the gateway to homemade kefir, labneh, and skyr.
Inputs / outputs
- Milk: any milk (cow, goat, sheep, soy, oat, almond — non-dairy yields require added thickener)
- Inoculation: 1–2 tbsp yogurt per quart milk, or commercial dry starter per packet
- Temperature: 105–115°F (40–46°C); below 100°F bacteria sluggish, above 120°F bacteria die
- Time: 4–12 hours (longer = tangier, thicker)
- Output: ~5–6% [[lactic-acid|lactic acid]] yogurt, refrigerator-stable 2 weeks; fresh enough culture for next batch
Solves / unlocks
- Daily yogurt production at home (penny-on-the-dollar vs commercial)
- Heirloom-culture preservation (Bulgarian, Caspian Sea, Greek strains held vegetatively for generations)
- Greek yogurt / labneh / skyr (yogurt + drain in cheesecloth)
- Kefir (separate culture — kefir grains, mesophilic, yields effervescent drink)
- Cheese-making bridge (similar bacteria, different processing)
- Fermented-dairy diversity (kvass, viili, filmjölk — regional traditions)
Constraints
- Temperature precision — most failures come from cooling milk improperly or maintaining temp poorly. Insulated cooler with hot water, yogurt maker, oven with light on, or sous-vide all work.
- Heirloom cultures need regular refresh — make a batch every 5–7 days or freeze a small portion as a backup.
- Antibiotic residue in milk can kill culture; raw or pasture-raised milk works best, ultra-pasteurized milk works fine but is denatured-protein different texture.
- Non-dairy yogurts need pectin or other thickener; the bacteria do not produce yogurt structure on plant milks alone.
Source
- Cultures for Health: https://culturesforhealth.com/ (commercial freeze-dried)
- Yemoos Nourishing Cultures: https://www.yemoos.com/ (heirloom strains)
- [[the-art-of-fermentation|The Art of Fermentation]] ([[sandor-katz|Sandor Katz]]) — dairy chapter
- Yogurt Culture (Cheryl Sternman Rule) — modern application
See also
Auto-generated from this entry’s typed relations: frontmatter, grouped by relation type so the editorial signal isn’t flattened.
- Parallels: [[lacto-fermentation]]
- Member of: [[ingredient]]
- Combines with: [[salt-cure]]
What links here, and how
Inbound connections from across the wiki, grouped by lens and by relationship. These appear automatically — every entity page declares what it links to, and that data populates here on the targets.
Scientific
parallels
- The microbe as collaborator the dairy-microbiome partnership that made nomadic-pastoralist civilizations milk-tolerant
Practical
parallels
- Cheese cultures yogurt cultures are simpler subset of cheese cultures; mesophilic cheese cultures often include the same Lactococcus/Lactobacillus species
contains
- Preservation toolkit microbial / thermophilic dairy lactic-acid culture
3 inbound links · 3 outbound