Reproducibility of the creamatocrit technique for the measurement of fat content in human milk

Wan Jun Tie; Jacqueline Coral Kent; Ching Tat Lai; Alethea Rea; Anna Rachel Hepworth; Kevin Murray; Donna Tracy Geddes

doi:10.1016/j.foodchem.2021.129708

Reproducibility of the creamatocrit technique for the measurement of fat content in human milk

Food Chem. 2021 Sep 15:356:129708. doi: 10.1016/j.foodchem.2021.129708. Epub 2021 Mar 26.

Authors

Wan Jun Tie¹, Jacqueline Coral Kent², Ching Tat Lai³, Alethea Rea⁴, Anna Rachel Hepworth⁵, Kevin Murray⁶, Donna Tracy Geddes⁷

Affiliations

¹ School of Molecular Sciences, The University of Western Australia, Perth, Western Australia, Australia. Electronic address: ash.tie@uwa.edu.au.
² School of Molecular Sciences, The University of Western Australia, Perth, Western Australia, Australia. Electronic address: Jacqueline.kent@uwa.edu.au.
³ School of Molecular Sciences, The University of Western Australia, Perth, Western Australia, Australia. Electronic address: ching-tat.lai@uwa.edu.au.
⁴ Faculty of Engineering and Mathematical Sciences, Mathematics and Statistics, The University of Western Australia, Perth, Western Australia, Australia; College of Science, Health, Engineering and Education, Academic Operations, Information Technology, Mathematics and Statistics, Murdoch University, Perth, Western Australia, Australia. Electronic address: alethea.rea@murdoch.edu.au.
⁵ School of Molecular Sciences, The University of Western Australia, Perth, Western Australia, Australia. Electronic address: arhepworth@westnet.com.au.
⁶ School of Population and Global Health, The University of Western Australia, Perth, Western Australia, Australia. Electronic address: kevin.murray@uwa.edu.au.
⁷ School of Molecular Sciences, The University of Western Australia, Perth, Western Australia, Australia. Electronic address: donna.geddes@uwa.edu.au.

PMID: 33845253
DOI: 10.1016/j.foodchem.2021.129708

Abstract

Quantification of human milk (HM) fat is important for determining the energy intake of infants. The simplest and most rapid method is the creamatocrit method. However, the reliability of the creamatocrit has not been comprehensively investigated. The aims of this study were to test the inter- and-intra-rater reliability of: 1) HM sampling after hand- or-machine mixing methods and 2) HM fat measurement by the creamatocrit method. Inter-and-intra rater HM sampling after hand- or-machine mixing methods had high intraclass correlation coefficient (>0.91). Inter-rater reliability of measurement of HM with low fat (<2%) resulted in high variability (median coefficient of variations (CVs) > 15%). Intra- and inter-rater reliability of measurement of HM with higher fat (>3.5%) had low variability (median CVs < 10%). As the greatest variation in the creamatocrit method occurred during the measurement of HM samples with low fat, duplicate readings are necessary to reduce discrepancies in every HM fat determination.

Keywords: Breast milk; Creamatocrit; Human milk; Lipid; Milk fat; Milk lipid.

MeSH terms

Fatty Acids / analysis*
Food Analysis / methods*
Humans
Infant
Milk, Human / chemistry*
Reproducibility of Results

Substances

Fatty Acids