Sodium caseinate and vitamin A uptake in lab cells
What it found
In lab tests with Caco-2 cells, vitamin A was taken up better when it was bound to certain sodium caseinate complexes than when it was free.
The highest uptake was seen with milk fortified with the reassembled succinylated complex.
What they found
Animal and lab studies
Protection during digestion
Vitamin A broke down under the acidic stomach conditions of the lab digestion model. Sodium caseinate protected it, so more vitamin A remained in the digested mixture than when vitamin A was added alone in oily form.
Uptake by cells
Caco-2 cells took up vitamin A differently from the digested sodium caseinate-vitamin A complexes compared with free vitamin A.
Protein digestion
Changing the make-up of the complex affected how well the protein was digested and how the resulting peptides were distributed.
Milk fortification
When Caco-2 cells were exposed to digested milk fortified with the different complexes, total vitamin A uptake was highest for milk with the reassembled succinylated complex, followed by the reassembled complex, control milk, the succinylated complex, the plain complex and free vitamin A.
Why reassembled worked better
The reassembled complexes exposed more water-repelling sites, which let vitamin A attach to the inner water-repelling parts of the sodium caseinate molecule. This made vitamin A more stable during digestion and led to more being available for the cells to take up.
What the authors conclude
“This led to higher stability of VA during gastrointestinal digestion and further resulted in higher bioaccessibility and bioavailability of vitamin A in Caco-2 cells.”
Also in their conclusions
- They conclude that reassembling the complexes exposes more hydrophobic sites, leading to higher stability of vitamin A during digestion.
- They state that this resulted in higher bioaccessibility and bioavailability of vitamin A in Caco-2 cells.
How it was done
Vitamin A breaks down in the acidic conditions of the stomach, so the authors wanted to see whether sodium caseinate could protect it during digestion and improve how much the body can take up.
They prepared four sodium caseinate-vitamin A complexes and tested them in a lab model of digestion using Caco-2 cells. They also measured how much vitamin A the cells took up from milk fortified with each complex.
What it can’t tell you
- We summarised it from the abstract only.
- These are lab tests using Caco-2 cells, not studies in people. They cannot show what happens in the human body.
- The lab digestion model cannot fully copy the complex conditions of real human digestion.
Who paid
- Authors work at
- National Dairy Research Institute, India; College of Dairy Technology, India
The paper
- Title
- Effect of sodium caseinate and vitamin A complexation on bioaccessibility and bioavailability of vitamin A in Caco-2 cells
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Abstract only
- Cite
- Rana S, Arora S, Gupta C, Kapila S (2019). Effect of sodium caseinate and vitamin A complexation on bioaccessibility and bioavailability of vitamin A in Caco-2 cells. Food research international (Ottawa, Ont.). doi:10.1016/j.foodres.2019.01.019PubMed 31108825DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error