Feeding premature infants banked human milk homogenized by ultrasonic treatment

Homogenised and pasteurised human milk: lipid profile and effect as a supplement in the enteral diet of Wistar rats

The retention of human milk (HM) fat in nasogastric probes of infusion pumps can be observed during the feed of infants unable to suck at the mother's breast. The lack of homogenisation of HM could contribute to the fat holding. Therefore, the present study evaluated (i) the influence of homogenisation on milk fat retaining in infant feeding probes and (ii) the in vivo effect of the homogenisation on lipid absorption by Wistar rats. The animals were fed with HM treated following two processing conditions, that is, pasteurised and homogenised-pasteurised. The animals were randomly subdivided into four experimental groups: water-fed (control), pasteurised milk, homogenised-pasteurised milk and pasteurised-skimmed milk. The results of food consumption, mass body gain, corporate metrics and plasma blood levels of total cholesterol did not show any difference (P < 0·05) among the three types of HM used in the experiments. The liver, intestine and intra-abdominal adipose tissue of the four groups of animals presented normal and healthy histology. The composition of fatty acids in the brain tissue of animals fed with homogenised HM increased when compared with the groups fed with non-homogenised HM. These values were 11·08 % higher for arachidonic acids, 6·59 % for DAH and 47·92 % for nervous acids. The ingestion of homogenised HM promoted higher absorption of milk nutrients. Therefore, the addition of the homogenisation stage in HM processing could be an alternative to reduce fat retention in probes and to improve the lipids' absorption in the body.

The Impact of Homogenization on Donor Human Milk and Human Milk-Based Fortifiers and Implications for Preterm Infant Health

An exclusive human milk diet (EHMD) has been shown to reduce health complications of prematurity in infants born weighing ≤1250 g compared with cow milk-based diets. Accordingly, the number of available human milk (HM)-based nutritional products continues to increase. Newly available products, and those reportedly soon to enter the market, include homogenized donor HM and homogenized HM-based fortifiers. Existing literature demonstrating the benefits of an EHMD, however, is limited to non-homogenized HM-based products. Herein, we summarize existing evidence on the impact of homogenization on HM, with a particular focus on changes to the macromolecular structure of the milk fat globule and the subsequent impact on digestion kinetics. We use these published data to create a conceptual framework for the potential implications of homogenized HM-based nutritional products on preterm infant health. Importantly, we underscore that the safety and efficacy of homogenized HM-based products warrant investigation.

Fat Loss in Continuous Enteral Feeding of the Preterm Infant: How Much, What and When Is It Lost?

Human milk fat is a concentrated source of energy and provides essential and long chain polyunsaturated fatty acids. According to previous experiments, human milk fat is partially lost during continuous enteral nutrition. However, these experiments were done over relatively short infusion times, and a complete profile of the lost fatty acids was never measured. Whether this loss happens considering longer infusion times or if some fatty acids are lost more than others remain unknown. Pooled breast milk was infused through a feeding tube by a peristaltic pump over a period of 30 min and 4, 12 and 24 h at 2 mL/h. Adsorbed fat was extracted from the tubes, and the fatty acid composition was analyzed by gas chromatography-mass spectrometry. Total fat loss (average fatty acid loss) after 24 h was 0.6 ± 0.1%. Total fat loss after 24 h infusion was 0.6 ± 0.1% of the total fat infused, although the highest losses occur in the first 30 min of infusion (13.0 ± 1.6%). Short-medium chain (0.7%, p = 0.15), long chain (0.6%, p = 0.56), saturated (0.7%, p = 0.4), monounsaturated (0.5%, p = 0.15), polyunsaturated fatty (0.7%, p = 0.15), linoleic (0.7%, p = 0.25), and docosahexaenoic acids (0.6%, p = 0.56) were not selectively adsorbed to the tube. However, very long chain fatty (0.9%, p = 0.04), alpha-linolenic (1.6%, p = 0.02) and arachidonic acids (1%, p = 0.02) were selectively adsorbed and, therefore, lost in a greater proportion than other fatty acids. In all cases, the magnitude of the loss was clinically low.

A Novel Approach to Improving Fat Delivery in Neonatal Enteral Feeding

Continuous infusion systems used for enteral nutrition support in the neonatal intensive care unit deliver as little as 60% of the fat in human milk to the neonate. This study determined the effect of mixing common feedings for preterm infants in the feeding bag and tubing on fat losses during enteral feeding. Laboratory models were developed to assess the contribution of various mixing techniques to delivered fat content. Fat content was measured periodically during feeding and compared to baseline measurements. A multistage approach incorporating a feeding bag inverter and a tubing circulation loop delivered >90% of milk fat when used in conjunction with a commercial continuous infusion system. With unfortified human milk, this approach delivered 91.9% ± 1.5% of fat content over a one hour feed, significantly greater (p < 0.01) than 77.5% ± 2.2% delivered by continuous infusion controls (Mean ± SEM). With fortified human milk, this approach delivered 92.1% ± 2.4% of fat content, significantly greater (p < 0.01) than 79.4% ± 1.0% delivered by a non-adapted infusion system (Mean ± SEM). Mixing human milk during continuous infusion improves fat delivery, which may improve nutrition and growth outcomes in low birth weight neonates.

Fortifier and cream improve fat delivery in continuous enteral infant feeding of breast milk

Premature and high-risk infants require accurate delivery of nutrients to promote appropriate growth. Continuous enteral feeding methods may result in significant fat and micronutrient loss. This study evaluated fat loss in enteral nutrition using current strategies for providing high-risk infants fortified human milk (HM). The fat content of HM was measured by IR analyzer in a simulated feeding system using the Kangaroo epumpTM and the MedFusionTM 2010 pump. Comparisons in fat loss were made between HM, HM supplemented with donor HM-derived fortifier Prolacta+H2MFTM (H2MF), and HM supplemented with H2MF and donor HM-derived cream ProlactCRTM (cream). When using the Kangaroo epumpTM, the addition of H2MF and cream to HM increased fat delivery efficiency from 75.0%±1.2% to 83.7%±1.0% (p<0.0001). When using the MedFusionTM 2010 pump, the addition of H2MF to HM increased fat delivery efficiency from 83.2%±2.8% to 88.8%±0.8% (p<0.05), and the addition of H2MF and cream increased fat delivery efficiency to 92.0%±0.3% (p<0.01). The addition of H2MF and cream to HM provides both the benefits of bioactive elements from mother's milk and increased fat delivery, making the addition of H2MF and cream an appropriate method to improve infant weight gain.

Effect of freezing time on macronutrients and energy content of breastmilk

BACKGROUND

In neonatal units and human milk banks freezing breastmilk at less than -20 °C is the choice for preserving it. Scientific evidence in relation to the loss of nutritional quality during freezing is rare. Our main aim in this study is to determine the effect of freezing time up to 3 months on the content of fat, total nitrogen, lactose, and energy. Our secondary aim is to assess whether ultrasonic homogenization of samples enables a more suitable reading of breastmilk macronutrients with a human milk analyzer (HMA) (MIRIS, Uppsala, Sweden).

METHODS

Refrigerated breastmilk samples were collected. Each sample was divided into six pairs of aliquots. One pair was analyzed on day 0, and the remaining pairs were frozen and analyzed, one each at 7, 15, 30, 60, and 90 days later. For each pair, one aliquot was homogenized by stirring, and the other by applying ultrasound. Samples were analyzed with the HMA.

RESULTS

By 3 months from freezing with the two homogenization methods, we observed a relevant and significant decline in the concentration of fat and energy content. The modification of total nitrogen and lactose was not constant and of lower magnitude. The absolute concentration of all macronutrients and calories was greater with ultrasonic homogenization.

CONCLUSIONS

After 3 months from freezing at -20 °C, an important decrease in fat and caloric content is observed. Correct homogenization is fundamental for correct nutritional analysis.

The macronutrients in human milk change after storage in various containers

BACKGROUND

The concentrations of macronutrients in human milk can be influenced by various processes, such as storage, freezing, and thawing, that are performed by lactating working mothers and breast milk banks. We evaluated the impact of various containers on the nutrient concentrations in human milk.

METHODS

A total of 42 breast milk samples from 18 healthy lactating mothers were collected. A baseline macronutrient concentration was determined for each sample. Then, the breast milk samples were divided and stored in nine different commercial milk containers. After freezing at -20°C for 2 days, the milk samples were thawed and analyzed again. A midinfrared human milk analyzer (HMA) was used to measure the protein, fat, and carbohydrate contents.

RESULTS

There was a significant decrease in the fat content following the storage, freezing, and thawing processes, ranging from 0.27-0.30 g/dL (p=0.02), but no significant decrease in energy content (p=0.069) was noted in the nine different containers. There were statistically significant increases in protein and carbohydrate concentrations in all containers (p=0.021 and 0.001, respectively), however there were no significant differences between the containers in terms of fat, protein, carbohydrate, or energy contents.

CONCLUSION

Human milk, when subjected to storage, freezing, and thawing processes, demonstrated a significant decrease in fat content (up to 9% reduction) in various containers. It is better for infants to receive milk directly from the mother via breastfeeding. More studies are warranted to evaluate the effects of milk storage on infant growth and development.

Effect of supplementation of preterm formula with long chain polyunsaturated Fatty acids on mineral balance in preterm infants

BACKGROUND

Incorporation of long chain polyunsaturated fatty acids (LCP) into formulas may interfere with mineral metabolism. We investigate mineral balance in preterm infants who were fed a formula with LCP.

METHODS

Infants were randomized in a double-blind manner, 20 infants in each group, to receive a formula with LCP (F+LCP) or without LCP (F) for 30 days. Plasma levels (at the beginning and after 30 days) and nutritional balance (after 1 week) for Ca, P, Mg, Zn, and Cu were obtained for all infants.

RESULTS

Groups were similar regarding birth weight, gestational age, weight, and corrected age at study start. During the 30-day study period, the groups had comparable milk intake and reached similar and satisfactory weight gains and longitudinal growth. Within each group, there was no change in plasma mineral concentrations over the course of the study, and there were no differences at each time point between groups. All values were within the normal range for age. No differences in mineral balance were detected between the F and F+LCP groups, with both groups demonstrating comparable intake, net retention, and fecal losses of each mineral.

CONCLUSIONS

Adding a content of LCP blend similar to that of human milk to a preterm formula caused no disturbance in Ca, P, Mg, Zn, or Cu nutritional balance.

Milk banking: the influence of storage procedures and subsequent processing on immunologic components of human milk

The immunoprotective constituents of human milk are stable when stored at room temperature for 8 hours, when stored at 0 degree-4 degrees C for three days, or when frozen at -20 degrees C for 12 months. They are also stable during pasteurization at 56 degrees C for 30 minutes. Sonification may reduce levels of sIgA and lysozyme and the ability of milk to inhibit growth of E coli. The number of cells in human milk is reduced by storage, freezing, pasteurizing, microwaving and sonification, and the functional capacity of surviving cells is also reduced.

Fat content and fatty acid composition of fresh, pasteurized, or sterilized human milk

In hospitals, human milk is subjected to heat treatment to reduce risk of transmission of infectious agents such as human immunodeficiency virus (HIV), hepatitis B, cytomegalovirus, and bacterial contamination, especially during feeding of banked milk to preterm infants. Fat losses due to heat treatment have been extensively studied in cow milk but have received little attention in human milk. We studied the effect of human milk pasteurization and sterilization on total fat content available to the infant as well as on fatty acid composition. Milk samples from 12 mothers (days 5-35 of lactation) were divided into three equal parts: one remained fresh, one was pasteurized (62.5 degrees C for 30min), and one was sterilized (120 degrees C for 30min). Fat content was determined gravimetrically, and the contribution of 30 fatty acids was determined by gas chromatography. For investigation of loss of available fat in sterilized milk, milk was collected from two additional mothers and analyzed with a modified extraction method. Total fat content was the same in fresh, pasteurized, and sterilized milk. The available fat content was 3.1+/-0.4g/dL (mean +/- SE) in fresh human milk, 3.1+/-0.4g/dL in pasteurized human milk, and 2.7+/-0.3g/dL (P < 0.001 vs. fresh) in sterilized human milk because of formation of a surface skin and fat adherence to the vial wall after sterilization. The fatty acid composition of 10 saturated, 10 monounsaturated, and 10 polyunsaturated fatty acids of both the n6 and n3 series was not affected by pasteurization. In sterilized milk there was a slight decrease of linoleic acid (C18:2n6; -0.7% vs. fresh; P = 0.006) and arachidonic acid (C20:4n6; -2.5%; P = 0.045). Pasteurization and sterilization do not affect total fat content of human milk, but sterilization may reduce available fat content by >10%. Fatty acid composition of human milk is not changed by pasteurization, but is slightly changed by sterilization.

Cutaneous application of vegetable oil as a coadjutant in the nutritional management of preterm infants

BACKGROUND

The cutaneous application of vegetable oil as a therapeutic practice and dietary coadjuvant has been described mainly in adult patients at risk for essential fatty acid deficiency. In the current study, the effects of cutaneous soybean oil application on somatic growth and plasma linoleic and arachidonic acid levels were examined in enterally fed preterm newborns.

METHODS

Sixty consecutive preterm infants were chosen from patients admitted to the nursery. Infants were randomly assigned to one of two groups: the oil group, which was treated cutaneously with soybean oil, or the control group, which received no cutaneous treatment.

RESULTS

After 30 days, a significant increase in anthropometric parameters was observed in infants who received cutaneous oil, mainly in infants small for gestational age. An increase in linoleic acid level and a decrease in arachidonic acid level were seen in both groups but do not justify the difference found in growth rates in the control and oil groups.

CONCLUSIONS

Preterm infants treated cutaneously with soy oil showed better somatic growth than the control group. The factors leading to the present results, especially the response of the infants who were small for gestational age merit further evaluation.

Storage of human milk and the influence of procedures on immunological components of human milk

The storage of human milk for use later by the mother's own infant or an unrelated recipient has an impact on its constituents. These effects involve the storage container, heating, cooling and freezing the milk. Overall, glass is the least destructive container. Milk can be safely refrigerated for 72 h with little change. Freezing destroys cellular activity and reduces vitamins B6 and C. Boiling, in addition, destroys lipase and reduces the effect of immunoglobulin A and secretory immunoglobulin A. The nutrient value of human milk is essentially unchanged, but the immunological properties are reduced by various storage techniques.