Evaluation of human milk titratable acidity before and after addition of a nutritional supplement for preterm newborns [Avaliação da acidez titulável do leite humano antes e após adição de um suplemento nutricional para recém-nascido pré-termo]

Objective to evaluate the initial dornic acidity in raw human milk,after pasteurization and after heating and dilution of a dietary supplement for preterm infants. methods a quantitative,descriptive,and experimental study was carried out with a convenience sample at the human milk bank at a brazilian public maternity,with specialized care for pregnant women and newborns at risk. the eligibility criteria for the study sample included 93 frozen raw human milk in suitable containers with volumes ≥100 ml and initial dornic acidity ≤8° dornic (° d). milk acidity of human milk was measured in four stages: in raw human milk (initial); after pasteurization; after the heating of pasteurized milk and dilution of the supplement; and after thirty minutes of supplementation. results the initial acidity was 3.8° d ± 1.3 (95% ci: 3.56–4.09) with no significant difference in dornic acidity in pasteurized milk,which was 3.6° d ± 1.2 (95% ci: 3.36–3.87). the dilution of the supplement in pasteurized milk that was heated significantly increased mean dornic acidity to 18.6 °d ± 2.2 (95% ci: 18.18–19.11),which remained high after thirty minutes of supplementation at 17.8 °d ± 2.2 (95% ci: 17.36–18.27),considering p < 0.05. conclusions the study observed no significant differences in dornic acidity of raw human milk and pasteurized human milk; however,the dilution of a human milk supplementation caused a significant increase in acidity. further investigations are necessary on the influence of this finding on the quality of supplemented milk and its consequences on the health of preterm infants. © 2016