Study · The British journal of nutrition · 2012

Sweet buttermilk and Listeria infection in rats

What it found

In rats, sweet buttermilk powder reduced colonisation and spread of Listeria monocytogenes, but did not protect against Salmonella enteritidis.

The protection may come from blocking the bacteria from sticking to the gut lining.

What they found

Animal and lab studies

Listeria in rats

Rats fed sweet buttermilk powder had lower numbers of Listeria in their faeces, gut contents, and gut lining, and less spread to the spleen and liver, compared with rats fed skimmed milk powder.

Salmonella in rats

Sweet buttermilk powder did not reduce faecal excretion of Salmonella enteritidis in rats.

Killing by stomach contents

Stomach contents from rats fed sweet buttermilk killed Listeria better than stomach contents from rats fed skimmed milk. This was not due to acid, fatty acids, or the xanthine oxidase system.

Membrane lipids tested

Feeding rats sphingomyelin or phosphatidylcholine did not affect Listeria colonisation or spread, so these milk fats are not responsible for the protection.

Sticking to cells

In lab tests, sweet buttermilk powder stopped Listeria from sticking to red blood cells and to Caco-2 cells about four times and three times better than skimmed milk powder, but did not stop Salmonella from sticking.

What the authors conclude

“In conclusion, sweet buttermilk powder, which is rich in MFGM, protects against L. monocytogenes infection in rats, probably by preventing adherence of this pathogen to the intestinal mucosa.”
Sprong RC, Hulstein MF, Lambers TT, van der Meer R, 2012

Also in their conclusions

  • They conclude that sweet buttermilk powder, which is rich in milk fat globule membrane, protects against Listeria infection in rats, probably by preventing the bacteria from sticking to the gut lining.
  • They state that which specific compounds in sweet buttermilk cause this resistance is not known and needs further research.
  • They advise that more work is needed to find the exact mechanism and the individual components responsible.

How it was done

The milk fat globule membrane in buttermilk contains antimicrobial components that work in lab tests, but evidence in living animals is scarce. The authors wanted to test whether these components actually protect against gut infections in a whole animal.

Rats were fed diets based on either skimmed milk powder (low in milk fat globule membrane) or sweet buttermilk powder (high in it) for 14 days, then infected with Salmonella enteritidis or Listeria monocytogenes. In separate experiments, rats were fed sphingomyelin or phosphatidylcholine, and lab tests measured how well buttermilk powder stopped Listeria from sticking to cells.

What it can’t tell you

  • These are animal and lab studies. They cannot show whether sweet buttermilk would protect people against Listeria or any other infection.
  • The study does not show which compound in buttermilk is responsible for the effect.
  • The results apply only to the specific strains of Listeria and Salmonella used, and to rats fed these particular diets.

The paper

Title
Sweet buttermilk intake reduces colonisation and translocation of Listeria monocytogenes in rats by inhibiting mucosal pathogen adherence
Type
Study
Evidence
Animals and lab studies
Summarised from
Full text
Cite
Sprong RC, Hulstein MF, Lambers TT, van der Meer R (2012). Sweet buttermilk intake reduces colonisation and translocation of Listeria monocytogenes in rats by inhibiting mucosal pathogen adherence. The British journal of nutrition. doi:10.1017/S0007114512000165Free full textPubMed 22370235DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error