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Condition-aware microbial kinetics

Species Doubling Reference

Peer-reviewed starter, probiotic, and benchmark growth data for dairy and lab contexts

Bacterial Growth Database

Doubling times shown here are exponential-phase monoculture reference values. They vary with strain, substrate, oxygen, pH control, and buffering, so each card includes the reported temperature or medium-specific conditions when the paper provides them. Mixed-culture or cofermentation behavior can be materially faster than the values shown here and should not be inferred from these rows.

Entries 10 species
Scope Dairy + lab
Primary years 2000-2023
Reference Scope / Use At Your Own Risk

This page summarizes literature-reported microbial growth kinetics for comparison and educational use. Real doubling behavior varies with strain lineage, inoculum age, oxygen handling, medium composition, pH control, buffering, milk treatment, and measurement method.

Monoculture reference only. The displayed td values are mono-culture or single-organism benchmarks under the cited conditions. They should not be treated as direct mixed-culture, cofermentation, or symbiotic growth rates.

Not food safety advice. This is not a pathogen-safety model, HACCP tool, fermentation process validation, compliance reference, or substitute for direct pH, temperature, CFU, or contamination testing.

No warranty. No liability. No suitability claim. You assume all risk. The tool is provided as-is, without warranty of accuracy, completeness, merchantability, fitness for a particular purpose, or regulatory acceptability. The creators and maintainers expressly disclaim responsibility and liability for contamination events, spoiled batches, failed ferments, incorrect strain assumptions, product claims, shelf-life decisions, process release decisions, compliance failures, commercial losses, downstream damages, or any other consequence arising from use or misuse of this page.

Not a release criterion. Do not use this reference by itself to clear product for consumption, sale, labeling, patient use, or manufacturing decisions.

Cofermentation caveat. Protocooperation and cofermentation can yield effective doubling behavior far shorter than the mono-culture values shown here, especially for starter pairs such as S. thermophilus and L. bulgaricus.

Verify independently. Check the cited papers, validate conditions against your actual substrate, strain, and culture mix, and use qualified food-safety, microbiology, or production guidance before using any value for safety-critical, commercial, clinical, or regulatory decisions.

Compare Up To Six Species

Select one reported mono-culture td behavior per species. The chart normalizes all selections to the same starting abundance, plots doublings over custom time, and estimates a normalized endpoint share from independent mono-culture growth only. It is a back-of-the-envelope overlay, not a cofermentation model.

Live update. Enter a positive duration to refresh the plot and normalized endpoint share.

Selected species 0
Fastest td n/a
Largest normalized share n/a
Temperature spread n/a

Doubling Behavior Plot

Y-axis shows doublings from the same normalized starting point. Fold change is 2doublings.

Species doubling comparison chart Normalized comparison of selected species doubling behaviors over time.

Normalized Endpoint Share

Percentages below rescale each row's independent mono-culture endpoint from the same starting abundance. They are useful for quick endpoint comparison only and are not mixed-culture composition predictions.

Primary Yogurt Starters

Fast acidifiers and proteolytic partners used to drive classic yogurt fermentation.

S. thermophilus

Streptococcus thermophilus

Starter

Fast thermophilic starter that scavenges oxygen and produces metabolites that help its symbiotic partner acidify milk.

td (dairy)
30-45 min
μmax
1.23 +/- 0.09 h-1
Topt
~41°C
Reference medium
Whey + yeast extract

Reported conditions

  • 36°C, pH 5.7: μmax 0.759 h-1, td ~55 min
  • 40°C, pH 6.5: μmax 1.186-1.247 h-1, td ~33-35 min
  • 44°C, pH 7.3: μmax 1.087 h-1, td ~38 min

Sources

L. bulgaricus

Lactobacillus delbrueckii subsp. bulgaricus

Starter

Proteolytic thermophile that supplies peptides and drives acidification after S. thermophilus establishes the fermentation.

td
40-75 min (mean ~60)
μmax
1.25 +/- 0.08 h-1
Topt
43.5°C
Reference context
MPL lactose medium / whey models

Reported conditions

  • 42°C, MPL chemically defined lactose medium: td ~60 min; 40-75 min across 22 strains
  • 44°C, pH 5.7: μmax 1.013-1.330 h-1, td ~31-41 min
  • 48°C, pH 4.9: μmax 1.024 h-1, td ~41 min

Sources

Probiotic Adjunct Cultures

Supplemental cultures used for survival, labeling, and functionality rather than sheer acidification speed.

L. acidophilus

Lactobacillus acidophilus

Probiotic

Common adjunct probiotic that can grow well in lab culture but often slows down in milk because peptide availability becomes limiting.

td (lab)
~54 min
td (dairy)
60-150 min
μmax
0.22-0.77 h-1
Topt
37-42°C

Reported conditions

  • Constant culture: generation time ~54 min in controlled lab growth
  • Skim milk fermentation: early, mid, and late log phases documented during milk adaptation
  • Dairy benchmark: 60-150 min reported range across milk-oriented strains

Sources

L. reuteri

Limosilactobacillus reuteri

Probiotic

Useful probiotic adjunct, but slower than starter cultures in conventional dairy unless the substrate is made easier to metabolize.

td (MRS)
~130 min
td (SSF)
~58 min
μmax
0.14-0.31 h-1
Topt
37°C

Reported conditions

  • 37°C, MRS broth, pH 6.2: GT 2.17 h, μmax 0.14 h-1
  • 37°C, SSF flour blend, pH 6.0: GT 0.96 h, μmax 0.31 h-1
  • Fermentation takeaway: substrate choice cuts doubling time by more than half

Source

L. rhamnosus

Lacticaseibacillus rhamnosus

Probiotic

Widely used probiotic adjunct that grows acceptably at yogurt temperatures but usually trails the starter pair in raw acidification speed.

td (MRS)
~157 min
td (SSF)
~85 min
μmax
0.12-0.21 h-1
Topt
37-44°C

Reported conditions

  • 37°C, MRS broth, pH 6.2: GT 2.61 h, μmax 0.12 h-1
  • 37°C, SSF flour blend, pH 6.0: GT 1.41 h, μmax 0.21 h-1
  • SSF lag phase: ~1.98 h before acceleration

Source

L. plantarum

Lactiplantibacillus plantarum

Probiotic

Flexible acid-tolerant adjunct that appears more often in mixed or plant fermentations, but can still be benchmarked against dairy media.

td (MRS)
~124 min
td (SSF)
~82 min
μmax
0.15-0.22 h-1
Topt
30-37°C

Reported conditions

  • 37°C, MRS broth, pH 6.2: GT 2.06 h, μmax 0.15 h-1
  • 37°C, SSF flour blend, pH 6.0: GT 1.37 h, μmax 0.22 h-1
  • SSF adaptation: no clear lag phase reported

Source

L. casei / paracasei

Casei group reference

Probiotic

Commercial labels often collapse this group, so the reference combines paracasei kinetics with a whey-based casei benchmark where helpful.

td (MRS)
~99 min
td (SSF)
~66 min
μmax
0.18-0.27 h-1
Topt
37°C

Reported conditions

  • 37°C, MRS broth, pH 6.2: L. paracasei GT 1.65 h, μmax 0.18 h-1
  • 37°C, SSF flour blend, pH 6.0: L. paracasei GT 1.10 h, μmax 0.27 h-1
  • 37°C, whey + lactose: L. casei μmax 0.299 h-1 in deproteinized cheese whey

Sources

B. animalis subsp. lactis

BB-12-type bifidobacterial benchmark

Probiotic

Anaerobic bifidobacterial adjunct used for probiotic positioning rather than fast dairy acidification, with growth strongly tied to substrate and oxygen handling.

td
~106 min
μmax
~0.39 h-1
Topt
37°C
Condition
Anaerobic fortified MRS broth

Reported conditions

  • 37°C, fortified MRS broth with glucose: μmax 0.40 +/- 0.03 h-1, td ~104 min
  • 37°C, fortified MRS broth with lactose: μmax 0.38 +/- 0.03 h-1, td ~109 min
  • Interpretation: practical benchmark is about 100-110 min under anaerobic broth conditions

Source

Kinetic Benchmarks

Reference organisms that help anchor how fast or slow the yogurt-relevant cultures are by comparison.

E. coli K-12

Rich-medium laboratory benchmark

Benchmark

Standard lab comparator for very rapid growth in rich broth; included as a ceiling for what fast bacterial doubling looks like.

td
~20 min
μmax
~2.08 h-1
Topt
37°C
Medium
LB broth

Reported conditions

  • 37°C, rich medium: classic textbook-like doubling near 20 min

Source

L. monocytogenes

Listeria monocytogenes

Benchmark

Food-safety benchmark that tolerates cold storage and broad environmental stress, making it a useful contrast to fermentation-focused organisms.

td (37°C)
45-60 min
Topt
37°C
Cold growth
Possible near 0-4°C
Medium
BHI broth

Reported conditions

  • 37°C, BHI: doubling time approximately 45-60 min
  • 14°C, diluted BHI: doubling times 12.4-19.9 h reported for food-environment isolates
  • Cold storage risk: growth can still occur during refrigeration rather than fully stopping

Sources