Advances in techniques for reducing cholesterol in egg yolk: A review

Eggs are highly nutritious food whose high cholesterol content has been always an inconvenience due to concerns about the relationship between dietary cholesterol and atherosclerotic cardiovascular risk. As this remains uncertain, low cholesterol intake is recommended. This review deals with the techniques employed to reduce the cholesterol content in egg yolk once the egg is shelled. There are four main techniques: i) solvent extraction, ii) fractionation by centrifugation, iii) cholesterol chelates or adsorbents and iv) cholesterol biotransformation. Analyse of techniques, descriptions and recent advances are included in this review. Solvent extraction and cholesterol biotransformation allow to reduce up to 94.7% and 93.4%, respectively. However, both methods have not been scaled up due to food safety and economic reasons. Nowadays, fractionation by centrifugation and cholesterol chelates are the only feasible methods with industrial applications, obtaining up to 82% and 99%, respectively. Fractionation method can be considered the best because no substances are added.