title: Rapid measurement of human milk macronutrients in the neonatal intensive care unit: accuracy and precision of fourier transform mid-infrared spectroscopy.
abstract: BACKGROUND
  Although it is well established that human milk varies widely in macronutrient content, it remains common for human milk fortification for premature infants to be based on historic mean values. As a result, those caring for premature infants often underestimate protein intake. Rapid precise measurement of human milk protein, fat, and lactose to allow individualized fortification has been proposed for decades but remains elusive due to technical challenges.
  
  
  OBJECTIVE
  This study aimed to evaluate the accuracy and precision of a Fourier transform (FT) mid-infrared (IR) spectroscope in the neonatal intensive care unit to measure human milk fat, total protein, lactose, and calculated energy compared with standard chemical analyses.
  
  
  METHODS
  One hundred sixteen breast milk samples across lactation stages from women who delivered at term (n = 69) and preterm (n = 5) were analyzed with the FT mid-IR spectroscope and with standard chemical methods. Ten of the samples were tested in replicate using the FT mid-IR spectroscope to determine repeatability.
  
  
  RESULTS
  The agreement between the FT mid-IR spectroscope analysis and reference methods was high for protein and fat and moderate for lactose and energy. The intra-assay coefficients of variation for all outcomes were less than 3%.
  
  
  CONCLUSIONS
  The FT mid-IR spectroscope demonstrated high accuracy in measurement of total protein and fat of preterm and term milk with high precision.
authors.affiliation: 1Department of Food Science and Technology, University of California Davis, Davis, CA, USA.
authors.forename: Jennifer T
authors.initials: JT
authors.lastname: Smilowitz
authors.forename: Deborah S
authors.initials: DS
authors.lastname: Gho
authors.forename: Majid
authors.initials: M
authors.lastname: Mirmiran
authors.forename: J Bruce
authors.initials: JB
authors.lastname: German
authors.forename: Mark A
authors.initials: MA
authors.lastname: Underwood
mesh_terms: D004041:Dietary Fats; D004044:Dietary Proteins; D005260:Female; D005502:Food / Q000145:classification*; D006801:Humans; D007363:Intensive Care Units, Neonatal; D008895:Milk, Human / Q000201:enzymology* / Q000382:microbiology; D000067716:Point-of-Care Testing / Q000592:standards*; D011247:Pregnancy; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods / Q000592:standards*; D013997:Time Factors
chemical_list: D004041:Dietary Fats; D004044:Dietary Proteins
keywords: Fourier transform; breast milk; breastfeeding; fat; lactose; mid-infrared spectroscopy; nutrition; point-of-care testing; preterm infants; protein