SIMPLE AND RAPID MACRONUTRIENT ANALYSIS OF HUMAN-MILK FOR INDIVIDUALIZED FORTIFICATION - BASIS FOR IMPROVED NUTRITIONAL MANAGEMENT OF VERY-LOW-BIRTH-WEIGHT INFANTS

Feeding human milk exclusively to the very-low-birth-weight infant may lead to insufficient intakes of protein and energy. Although the milk is therefore often supplemented with protein and additional calories, there is usually no prior information on its macronutrient compositio n. If such data were available, it would be possible to individualize the fortification of the milk. To find simple, rapid, and inexpensive methods of enriching it, we evaluated existing macronutrient assays of human milk. Thirty frozen samples of early human milk (3-20 days of l actation) were analyzed for contents of protein (Kjeldahl, Lowry, and Bio-Rad protein assays), fat (Folch, total lipids assay, and creamatoc rit), and carbohydrates (lactose and orcinol assays). The methods were modified to minimize cost and time. From these data, we find it appro priate to recommend the use of the Lowry (or, alternatively, the Bio-R ad) protein assay, the total lipids assay, and the orcinol carbohydrat e assay for reasonably accurate determinations of the protein and ener gy contents of human milk. Because the variation in the carbohydrate c ontent of human milk is very small, a more simple alternative approach would be to include only an average carbohydrate value for an estimat e of energy content. These low-cost methods can be used in all laborat ories affiliated to neonatal units taking care of preterm infants. Suc h individualized fortification should serve to further improve the nut ritional management of very-low-birth-weight infants.