Fructooligosaccharides and sulfur metabolites from meat in lab digestion
What it found
In lab tests, adding fructooligosaccharides to meat and fish during digestion raised hydrogen sulfide and short-chain fatty acids but lowered carbon disulfide, ammonia and indole.
The effects of fructooligosaccharides were larger than the differences between beef, pork, chicken and salmon.
What they found
Animal and lab studies
Sulfur metabolites
Adding fructooligosaccharides raised hydrogen sulfide by 36% and lowered carbon disulfide by 37%. It also suppressed the formation of dimethyl sulfides.
Short-chain fatty acids
With fructooligosaccharides, total short-chain fatty acids rose by 54%, and the pH dropped to 5.6 from 6.9. Acetate, propionate, butyrate and valerate all increased.
Protein fermentation
Adding fructooligosaccharides reduced ammonia by 60% and indole by 30%, and prevented phenol formation. Effects on cresol varied with the fecal sample used.
Meat type differences
Beef ferments tended to have 33 to 49% higher carbon disulfide levels than the other muscle sources. Red meat fermentation did not produce more hydrogen sulfide.
Salmon vs meat
Without fructooligosaccharides, salmon ferments had higher methanethiol and ammonia but lower indole than meat ferments. With fructooligosaccharides, salmon ferments had lower hydrogen sulfide than chicken ferments.
What the authors conclude
“In conclusion, there is a greater effect on sulfur fermentation by the addition of FOS to the meats, than the intrinsic heme-Fe content of meat.”
Also in their conclusions
- They conclude that fructooligosaccharides had a greater effect on sulfur fermentation than the heme iron content of the meats.
- They say that red meat fermentation did not result in higher formation of sulfur metabolites, except for a tendency towards higher carbon disulfide in beef ferments.
- They advise that their findings need to be tested and confirmed in live animals or people.
How it was done
The authors wanted to see whether heme iron in red meat increases sulfur metabolites during gut fermentation, and whether fructooligosaccharides change that. They note that sulfur metabolites from red meat fermentation may affect intestinal health.
They digested cooked beef, pork, chicken and salmon, with or without fructooligosaccharides, using a lab model of stomach and gut digestion. Then they fermented the mixtures for 24 hours with fecal samples from four healthy adults, in triplicate, repeated four times.
What it can’t tell you
- This was a lab model using fecal samples, not a study in people or animals. It cannot show what happens in the human gut.
- The lab model does not include absorption of metabolites or the gut's detoxification systems, so it cannot show real intestinal levels.
- The effects depended on which person's fecal sample was used, so results may vary between individuals.
Who paid
- Authors work at
- Ghent University, Belgium; Centre for Advanced Process Technology for Urban Resource Recovery (CAPTURE), Belgium
The paper
- Title
- The formation of sulfur metabolites during in vitro gastrointestinal digestion of fish, white meat and red meat is affected by the addition of fructo-oligosaccharides
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Elias Masiques N, Vossen E, De Vrieze J, De Smet S, Van Hecke T (2024). The formation of sulfur metabolites during in vitro gastrointestinal digestion of fish, white meat and red meat is affected by the addition of fructo-oligosaccharides. Food & function. doi:10.1039/d4fo00928bFree full textPubMed 39101364DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error