The Study
Improvement in the Coloration and Quality of Japanese Quail Eggs Through Supplementation with Natural Pigments
This study shows that quails given certain plant pigments tended to lay eggs with darker yolks and some changes in quality over time. But because we don’t know exactly how the study was done, we can’t say for sure that the pigments caused these changes — they might just be linked.
Analysis score
Maximum 72 for a cohort study.
Where the score came from
Scientists fed quails special plant powders to see how it changed their eggs' color and freshness over time.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 511 / 100
Quality score
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Key takeaways
Summary
Based on the study abstract and findings.
- 1The eggs looked better and stayed fresh a bit longer, but the quails were less efficient at turning food into eggs.
- 2Eggs from quails fed marigold had the most orange yolks and more beta-carotene (40 g/kg).
- 3All colorful feeds made yolks look better.
- 4But the quails needed more food to make eggs.
- 5Egg whites stayed fresher longer in eggs from supplemented quails.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Poultry
Year
2025
Authors
JK Valentim, Alexander Alexandre de Almeida, F. C. Serpa, Maria Fernanda de Castro Burbarelli, G. A. Félix, K. Gomes, Caio Cesar Ouros, F. R. Caldara, Silvia M. Martelli, C. Komiyama, R. G. Garcia
Related Content
Claims (5)
Farmers add paprika and marigold to chicken food to make egg yolks look more orange because people think those eggs are healthier—even if they're not.
Adding marigold flower extract to chicken feed makes egg yolks more colorful and boosts a healthy nutrient called beta-carotene, which might make eggs look better to shoppers.
Giving Japanese quails food with a little bit of paprika or marigold extract makes their egg yolks more colorful, which people usually like better.
If you feed Japanese quail a diet with 0.8% paprika, marigold, or both, they don’t turn their food into body weight or eggs as well as quail that don’t get those supplements.
Feeding quails natural plant pigments from paprika and marigolds might help keep their eggs fresher for longer by slowing down changes inside the egg as it's stored.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.