Storage of unfed and leftover pasteurized human milk

Objective: To determine the impact of storage on bacterial growth and immunological activity of pasteurized human milk and leftover pasteurized human milk that has been exposed to the microflora in an infant's mouth. Materials and Methods: Eighteen mother-infant dyads participated in two separate studies. Mother's milk was pasteurized, and each baby was fed 1 to 2 ounces. Pasteurized and leftover pasteurized milk were stored at room (24°C) and refrigerated temperatures (4°C). After storage, milk was analyzed for bacteria, total protein, lysozyme activity, and secretory immunoglobulin A (SIgA) activity. Results: In pasteurized and leftover pasteurized milk stored in the refrigerator for 7 days, total aerobic bacteria do not increase significantly and total protein and bioactive proteins are stable. At room temperature, there is a significant increase in total aerobic bacteria in leftover pasteurized milk during 12 hours of storage (p?<?0.01) and a significant decrease in total protein and SIgA activity in pasteurized milk during 12 hours of storage (p?=?0.02 and p?=?0.03, respectively). Conclusions: When stored in the refrigerator, pasteurized and leftover pasteurized milk may be stored for at least 7 days when considering the variables studied. Caution should be used when storing pasteurized and leftover pasteurized milk at room temperature to prevent an increase in bacterial growth and a decrease in total protein and SIgA activity

The effects of fortification and refrigerated storage on bioactive proteins in Holder-pasteurized donor human milk

Objective: The aim of the study was to assess the total protein, lysozyme, and immunoglobulin A (IgA) content of unfortified and fortified Holder-pasteurized donor human milk (HPDHM) during 96 hours of refrigerated storage. Study Design: HPDHM was prepared in a hospital feeding room and subjected to treatment with 3 different fortifiers: an acidic, bovine-based (F-ACID), a neutral, bovine-based, and a human milk–derived (F-HUM) fortifier. Unfortified HPDHM served as the control (CONTROL). Samples were stored at 4°C, and every 24 hours, a 1-mL aliquot was removed for analysis. Results: At baseline, there was a significant difference in protein (mean, standard deviation) concentration (g/dL) between control (1.3, 0.1) and all other treatments (F-ACID = 2.0, 0.2; neutral, bovine-derived fortifier = 2.2, 0.1; F-HUM = 2.5, 0.1; P 0.9) for all dependent variables. Conclusion: The type of fortifier has a more significant impact on bioactive components in fortified HPDHM than does storage time. Our findings of lack of negative impact of refrigeration storage time on the protein and bioactive components of donor milk strengthen the recent recommendations to extend storage time to 48 hours

A longitudinal study of human milk composition in the second year postpartum: Implications for donor milk banking

While the composition of human milk has been studied extensively in the first year of lactation, there is a paucity of data regarding human milk composition beyond one year postpartum. Policies vary at milk banks around the world regarding how long lactating women are eligible to donate their milk. The primary purpose of this study is to describe longitudinal changes in human milk composition in the second year postpartum to support the development of evidence based guidelines regarding how long lactating women can donate human milk to a milk bank. Nineteen lactating women in North Carolina provided monthly milk samples from 11 months to 17 months postpartum (N=131), and two non-profit milk banks provided (N=33) pooled, unpasteurized milk samples from 51 approved donors less than one year postpartum. There was a significant increase (P<0.05) in the concentration of total protein, lactoferrin, lysozyme, Immunoglobulin A, oligosaccharides and sodium in longitudinal samples of mother's milk between 11 and 17 months postpartum, while zinc and calcium concentrations declined, and no changes were observed in lactose, fat, iron and potassium. Human milk in the second year postpartum contained significantly higher concentrations of total protein, lactoferrin, lysozyme and Immunoglobulin A, than milk bank samples, and significantly lower concentrations of zinc, calcium, iron and oligosaccharides. Accepting milk bank donations beyond one year postpartum is a potential strategy for increasing the supply of donor milk, but may require mineral fortification

Vitamin B12 content in breast milk of vegan, vegetarian, and non-vegetarian lactating women in the United States

Background: The nutritional profile of human milk varies significantly between women, and the impact of maternal diet on these variations is not well understood. Objective: We analyzed breast-milk vitamin B-12 concentration and vitamin B-12 supplement use pattern among women who adhered to different dietary patterns: vegan, vegetarian, and nonvegetarian. Design: A total of 74 milk samples, 26 from vegan, 22 from vegetarian, and 26 from nonvegetarian breastfeeding mothers, were analyzed. Results: The prevalences of low vitamin B-12 ( 0.05). Conclusions: Almost 20% of our study participants were classified as having low breast-milk vitamin B-12 concentrations (<310 pmol/L), independent of maternal diet pattern. Approximately 85% of participants categorized as having low vitamin B-12 were taking vitamin B-12 supplements at doses in excess of the Recommended Dietary Allowance, which suggests that more research is needed to determine breast-milk adequacy values

The Nutritive and Immunoprotective Quality of Human Milk beyond 1 Year Postpartum: Are Lactation-Duration-Based Donor Exclusions Justified?

Donor human milk is critical for the fragile preterm infant who does not have access to his or her mother’s milk, improving survival rates and quality of survival and decreasing hospital stay. Despite the opening of donor milk banks around the world, shortages continue as demand for donor milk exceeds supply. One potential means of increasing supply is by reducing exclusion criteria that prohibit mothers from donating milk based on duration of lactation. Minimal research has been done on the composition of human milk during the second year of lactation, with most research focusing on the nutritive compounds and not the immunoprotective compounds. Several immunoprotective compounds, including lysozyme, lactoferrin, secretory immunoglobulin A, and oligosaccharides, are abundant in human milk compared to bovine-based infant formula and are partially or fully retained during Holder pasteurization, making them an important differentiating feature of donor milk. A PubMed search was conducted to review studies in human milk composition during the second year of lactation. Limitations of existing research include sample collection protocols, small study sizes, and use of populations that may have been at risk for nutritional deficiencies. Stable concentrations of several components were reported including protein, lactose, iron, copper, lactoferrin, and secretory immunoglobulin A. Lysozyme concentration increased during extended lactation, while zinc and calcium concentrations declined into the second year. Conflicting findings were reported on fat content, and no information was available regarding oligosaccharide content. More research is needed to create evidence-based guidelines regarding the nutritive and immunoprotective value of donor milk throughout the course of lactation

Total water-soluble choline concentration does not differ in milk from vegan, vegetarian, and non-vegetarian lactating women

Background: Choline is an essential nutrient for brain growth and other processes in the developing neonate. The impact of a maternal plant-based diet on the choline composition of breast milk is unknown. Objective: We assessed the water-soluble choline content of milk from lactating women in the United States following 3 dietary patterns: vegan, vegetarian, and nonvegetarian. Methods: We conducted a cross-sectional study of 74 healthy lactating women who provided a single breast-milk sample using a standardized collection protocol. Participants completed a food-frequency screener and were classified as follows: nonvegetarians (NONVEG) consumed meat; vegetarians (VEGT) consumed milk, dairy, and/or fish; and vegans (VEGAN) consumed animal products less than monthly. Primary outcomes measured were the concentration (in milligrams per liter) and distribution (percentage) of choline from the following water-soluble forms: free choline, phosphocholine (PCho), and glycerophosphocholine (GPC). Differences between diet groups were evaluated with ANOVA. Results: There was a wide range in breast-milk total water-soluble choline (4–301 mg/L), with no significant difference (P > 0.05) by maternal diet pattern. There were differences in choline forms, with VEGAN having a greater mean ± SD concentration and distribution of choline derived from GPC (62.7 ± 25.3 mg/L) than VEGT (47.7 ± 21.2 mg/L) and NONVEG (42.4 ± 14.9 mg/L) (P = 0.0052). There was a lower mean ± SD percentage of choline from PCho (P = 0.0106) in VEGAN (32.5% ± 18.3%) than in VEGT (46.1% ± 18.3%) and NONVEG (44.8% ± 15.7%). Lactation stage and maternal BMI were significantly associated with some choline forms. Conclusions: There was a wide range of water-soluble choline concentrations in the milk of healthy lactating women following vegan, vegetarian, and nonvegetarian diets, with no observed difference in total water-soluble choline concentration by maternal diet. This suggests that maternal plant-based diet by itself is not a risk factor for low breast-milk choline