Methyl cellulose slowed fat digestion in lab tests
What it found
In lab tests, emulsions made with methyl cellulose released less fat than those made with cellulose nanocrystals alone.
The work was done in test tubes and cells, not in people.
What they found
Animal and lab studies
Fat breakdown slowed
In the full three-stage digestion model, emulsions with methyl cellulose released 64% of free fatty acids, compared to 73% for cellulose nanocrystals alone. This suggests methyl cellulose slowed fat digestion.
Chitosan particles worked best
Emulsions where chitosan was complexed with cellulose nanocrystals before emulsification released only 56% of free fatty acids, the lowest among all tested. Adding chitosan sequentially gave 70% release.
Stability in digestive fluids
Adding methyl cellulose or chitosan increased droplet size and improved emulsion stability in simulated digestive fluids. The methyl cellulose and cellulose nanocrystal combination kept its structure better than cellulose nanocrystals alone.
Cell safety in lab tests
In tests on Caco-2 intestinal cells, none of the emulsions reduced cell viability under the conditions tested. Cell viability stayed close to 100% for cellulose nanocrystals alone.
Two digestion models compared
The simple intestinal model released less than 20% of free fatty acids, while the full three-stage model released about 70%. The authors say this shows the oral and gastric phases matter for how emulsions behave.
What the authors conclude
- They say their results show that cellulose nanocrystals combined with dietary fibre can be used in food products to control the rate of fat digestion.
- They note that the way the ingredients are mixed matters, with chitosan complexed to cellulose nanocrystals before emulsification giving the largest reduction in fat breakdown.
- They suggest that using a full digestion model is important when testing new formulations for their effect on fat digestion.
How it was done
The authors wanted to find ways to slow down fat digestion, as overeating fat is linked to obesity and related health problems. They tested whether combining cellulose nanocrystals with methyl cellulose or chitosan could make emulsions more stable and slow fat breakdown.
They made oil-in-water emulsions using cellulose nanocrystals alone or combined with methyl cellulose or chitosan, varying the order of mixing. They then put these emulsions through simulated digestion models, including a two-hour intestinal phase and a full three-stage model, and measured how much fat was broken down.
What it can’t tell you
- These are lab tests using simulated digestive fluids and cells. They cannot show what happens in people.
- The study did not measure how much fat is actually absorbed by the body, only how much is broken down in the test tube.
- The long-term effects of eating these emulsions were not tested.
Who paid
- Conflicts
- Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
- Authors work at
- Institute of Pharmaceutical Science, UK; King's College London, UK
The paper
- Title
- Controlling in vitro lipid digestion: Pickering emulsions with cellulose nanocrystals, chitosan and methylcellulose
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Zhang L, Halket J, Caldwell A, Vllasaliu D, Bajka B, Dreiss CA (2025). Controlling in vitro lipid digestion: Pickering emulsions with cellulose nanocrystals, chitosan and methylcellulose. Food research international (Ottawa, Ont.). doi:10.1016/j.foodres.2025.116793Free full textPubMed 40790654DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error