Research

A study conducted at CEU Cardenal Herrera University in Valencia highlights freeze-drying as an effective alternative for storing breast milk, surpassing traditional deep-freezing methods used in milk banks. Collaborating with La Fe Hospital, researchers found that freeze-drying maintains the antibacterial properties of breast milk and prevents microbiological contamination. Published in the Journal of Pediatric Gastroenterology and Nutrition, this study is one of the first to evaluate freeze-drying's impact on breast milk's antibacterial capacity. The research supports the adoption of freeze-drying as a viable and beneficial storage method in milk banks, particularly for premature or low birth weight infants, whose immune systems rely on breast milk's antibacterial benefits.

Although freezing is the most common method used to preserve human milk, nutritional and immunological components may be lost during storage. Freeze-drying could increase the shelf life of human milk, while preserving its original characteristics. Seventy-two samples of freeze-dried human milk were stored for different periods of time, up to a maximum of 3 months, at 4 °C or 40 °C. Vitamin C, tocopherols, antioxidant capacity, and fatty acids composition were analyzed. A new HILIC–UHPLC method improving vitamin C determination was also validated. Ascorbic acid and total vitamin C concentrations significantly decreased at both temperatures, while antioxidant capacity only decreased at 40 °C. Fatty acids composition and both γ-tocopherol and δ-tocopherol contents remained unaltered. The stability after storage of freeze-dried milk was higher than that reported for frozen or fresh milk indicating that freeze-drying is a promising option to improve the preservation of human milk in banks.

This study aimed to assess the effectiveness of freeze-drying as a method for preserving the properties of human milk without causing further oxidative damage. The research involved 116 healthy women from Cordoba, Argentina, and measured various components in their fresh breast milk. The samples were then subjected to different treatments, including freezing at -80°C, freeze-drying at -70°C and ≤1.33 Pa, and combinations of these methods, followed by storage for six months. The results showed that freeze-drying effectively preserved the nutritional properties, polyphenol-related functionality, and oxidative integrity of human milk. In contrast, freezing alone led to a decrease in glucose levels. The combination of freeze-drying and freezing did not provide additional benefits. In conclusion, freeze-drying was found to be a suitable method for preserving human milk, potentially improving the functionality of milk banks by ensuring the maintenance of essential properties with a straightforward one-day treatment.

This study aimed to investigate the impact of pasteurization and freeze-drying on human milk oligosaccharides (HMOs), important for neonatal neurological and immunological development. Fresh milk samples from three mothers were collected at different postpartum weeks and subjected to pasteurization and freeze-drying. HMO profiles were analyzed using mass spectrometry, revealing significant differences among mothers but no impact from lactation period or treatment. Both pasteurization and freeze-drying did not affect HMO profiles. The study supports the introduction of freeze-drying in human milk banks to maintain HMO composition, though further research on storage duration is needed.

This study aimed to investigate the impact of pasteurization and freeze-drying on the profiles of human milk oligosaccharides (HMOs), which are crucial for the neurological and immunological development of neonates. Nine fresh human milk samples from three different mothers were collected at various time points after delivery and subjected to Holder pasteurization and freeze-drying. The HMO profiles were analyzed using advanced mass spectrometry techniques and compared between the samples collected before and after these treatments. The results indicated that while there were significant variations in HMO patterns among mothers, the lactation period within the first three weeks after delivery did not affect HMOs. Furthermore, both pasteurization and freeze-drying were found to have no substantial impact on HMO patterns. In conclusion, this study suggests that pasteurization and freeze-drying do not alter the composition of HMOs in donor milks. The findings support the potential use of freeze-drying in human milk banks, but further research is needed to determine the stability of HMOs over extended storage periods after freeze-drying.

This study aimed to assess the effectiveness of different storage methods for human milk, specifically lyophilization and freezing at -20°C and -80°C. The research focused on evaluating their impact on microbiological content, bactericidal activity, and the potential relation with maternal factors. The results showed that both lyophilization and storage at -80°C were effective in reducing the content of microorganisms when compared to storage at -20°C. Bactericidal activity was not significantly affected by lyophilization, and it was found to be correlated with the content of gangliosides but not with fat, protein, or lactose levels. Bactericidal activity was also observed to be higher in mature milk and in milk from women with term deliveries compared to early lactation and milk from women with preterm deliveries.

In conclusion, lyophilization and storage at -80°C were identified as viable and superior alternatives for preserving human milk in comparison to storage at -20°C, both in terms of microbial and bactericidal capacities. These findings suggest that lyophilization can be a feasible method for human milk banks to ensure the safety and health benefits of stored breast milk.

This study examined the quality of lipids in lyophilized and vacuum-packed human milk, including colostrum, transitional milk, and mature milk, during storage at -18°C for various durations (1, 30, 60, 90, 120, 150, and 180 days). The research aimed to assess any changes in lipid composition. The results, which included acidity (ºDornic), lipid content, and fatty acid (FA) composition, did not reveal significant differences over the storage period. The relative percentages of major triacylglycerols (TAG) in human milk remained unchanged. This suggests that lyophilization is a viable method for preserving human milk, making it a practical option for human milk banks by facilitating transport and storage without compromising its lipid quality.

The study aimed to investigate the impact of freeze-drying on human milk (HM) proteins, which are essential for neonatal growth and development. Nine fresh HM samples were collected from three healthy mothers at 15 and 60 days into the lactation period. These samples were then subjected to freeze-drying, and a proteomic analysis was conducted using mass spectrometry. The results were compared between samples from different lactation periods and before and after freeze-drying. The study identified a total of 245 proteins in the HM samples. Interestingly, the expression of these proteins remained unaffected by both the lactation periods (15 and 60 days) and the freeze-drying process. Additionally, functional analysis of the proteomic data showed no significant differences between the two groups.

In conclusion, the study suggests that HM proteins are not significantly impacted by the lactation periods or the freeze-drying process. This finding supports the potential introduction of freeze-drying in HM banks. However, the study acknowledges the limited sample size and suggests further research to evaluate the safe storage duration concerning infectious agents and composition changes following freeze-drying.

A study from CEU Cardenal Herrera University in Valencia confirms that freeze-drying is an effective alternative for storing breast milk compared to the conventional deep-freezing method used in milk banks. Researchers collaborated with experts from La Fe Hospital's milk bank in Spain, highlighting that freeze-drying preserves breast milk without microbiological contamination and without compromising its health benefits, particularly its antibacterial properties. Published in the Journal of Pediatric Gastroenterology and Nutrition, this study is one of the few to assess freeze-drying for breast milk storage, focusing on its crucial antibacterial capacity. The research recommends the adoption of freeze-drying as a storage method in milk banks, especially for premature or low birth weight babies who rely on breast milk's antibacterial benefits. The study analyzed 125 breast milk samples from 65 mothers and compared the effects of freeze-drying with conventional freezing methods, concluding that freeze-drying is a viable alternative for preserving breast milk's natural properties.

This study explores the impact of freeze-drying after pasteurization, using three different pasteurization methods, on the levels of immunoglobulins and C3 complement in mature human milk (MHM). The objective is to propose freeze-drying as a supplementary method to better preserve the therapeutic properties of MHM.

The study involved obtaining MHM samples and subjecting them to pasteurization through varying temperature and time combinations, followed by rapid cooling. These pasteurized samples were then freeze-dried. The analysis included measuring total protein and the concentrations of immunoglobulins A, G, and M, as well as complement C3, using specific techniques.

The results revealed that pasteurization at 72 degrees Celsius before freeze-drying was most effective in retaining immunoglobulins. In conclusion, the study suggests that freeze-drying pasteurized MHM is a suitable approach for preserving it in human milk banks. This method maintains the nutritional composition and extends the validity of MHM, making it advantageous for providing therapeutic benefits to vulnerable, impaired, or immunosuppressed newborns.

The study explored various freeze-drying and spray-drying methods to assess their impact on the retention of immunoglobulins (Ig) A, IgG, and IgM in human milk. Spray drying resulted in human milk powders with 2% humidity and demonstrated excellent retention of IgG (>88%) and IgM (approximately 70%). However, IgA retention was only 38% after spray drying.

In contrast, for freeze-drying, the highest heating plate temperature tested (40°C) led to a reduction in IgA content to 55% in a powder with 1.75% residual humidity. Lower temperatures during the freeze-drying process yielded better preservation rates, with 75% retention for IgA and 80% for IgG and IgM, along with higher residual moisture levels.

In summary, IgA was found to be the most sensitive immunoglobulin affected during the drying process of human milk. The most effective method for generating human milk powders with minimal Ig loss was freeze-drying at a 30°C heating plate temperature, which sped up the process compared to lower temperatures while maintaining satisfactory Ig retention overall.

This study explored the potential of supplementing breast milk with freeze-dried human milk concentrate to meet the nutritional needs of very low birth weight infants. The research focused on assessing the lipid content and profile in different storage conditions.

The findings indicated that freeze-dried human milk with the concentrate had a higher lipid concentration compared to baseline breast milk. The study analyzed various fatty acids and observed minimal changes in their profiles during storage, with no evidence of peroxidation.

The results suggest that freeze-dried human milk fortified with a concentrate has the potential to provide essential nutrients crucial for the development of very low birth weight infants, particularly those present only in breast milk. However, further clinical studies are needed to determine the safety and effectiveness of this concentrate as a standard nutritional option for these infants.

The European Milk Bank Association (EMBA) formed a working group in 2015 to develop recommendations for the establishment and operation of human milk banks (HMB) in Europe. The group consisted of EMBA members with experience in guideline development and milk banking. They conducted a survey based on collated global recommendations, with 108 potential recommendations. Responses from members, noting which recommendations were included in their national guidelines, were collected and analyzed. The group reached consensus on certain recommendations and provided explanations for areas lacking consensus or clear evidence. The recommendations and consensus statements will be published on the EMBA website to support the safe operation of HMBs in Europe and will also inform the European Directorate for the Quality of Medicines & HealthCare (EDQM)'s Guide to the quality and safety of tissues and cells for human application in 2019.

Jose Simon Camelo Junior from the Universidade Federal de São Paulo in Brazil is undertaking research to develop a method for creating a lyophilized concentrate of human milk. This concentrate is intended for feeding very low birth weight newborns and can be implemented in developing countries. These extremely premature infants, weighing less than 1,500 grams, require significant amounts of proteins, calories, minerals, micronutrients, and electrolytes for their survival and growth. While breast milk is essential, it is often not concentrated enough to meet their needs. The commonly used supplements derived from cow's milk have shown to inhibit the immunological properties of human breast milk, which help protect against infections. Human milk additives have shown promise but are expensive to produce in developing nations. To address this challenge, the researchers are employing a straightforward method involving evaporation, centrifugation, and lyophilization to create a concentrated form of human milk. This concentrated milk will be evaluated for its stability, safety, and nutritional content, ensuring it contains the necessary concentrations of essential nutrients in manageable volumes to support the growth and development of very low birth weight newborns.

Researchers are exploring the potential of developing breast milk-based products, harnessing the beneficial components of breast milk for the health of infants and adults. These products could serve as supplements for infants with specific needs and potentially benefit sick adults. The internet has facilitated the aggregation of small-scale breast milk suppliers, opening up a new world of breast milk-based products. Various companies are working on such products, including those focusing on human oligosaccharide products, traditional non-profit milk banks, and those adapting breast milk in innovative ways such as creating shelf-stable liquid breast milk and freeze-dried breast milk.

The challenge lies in ensuring these products maintain the biological activity of breast milk's crucial components, which is vital for their efficacy. While there are still questions about affordability and ethical concerns regarding commodifying breast milk, breast milk-based products hold the potential to enhance the health of infants who rely on formula, as they can offer the unique combination of nutrients found in breast milk. Ongoing research will be crucial to maintain the biological functions of these products in convenient and affordable formulations for hospitals, health insurers, and parents.

Preserving an adequate supply of fresh human milk is often a challenge, making it crucial to find preservation methods that maintain its quality. Freeze-drying has proven effective, yielding approximately 12.5 grams of powder from 100 grams of fresh milk. Bacteriological tests conducted on the powder stored at room temperature for four weeks in sealed containers showed no significant increase in bacterial count. Electrophoresis testing on the re-dissolved milk indicated that the migration velocity of various fractions remained largely unchanged. Unlike boiling and pasteurization, which significantly alter the electrophoretic properties of individual fractions, this preservation method appears to avoid denaturation. Administration of this preserved milk to six premature babies over an extended observation period did not reveal any notable differences compared to fresh human milk.

Breast milk, which is in high demand and can cost between $2 and $6 per ounce, is difficult and expensive to preserve. The high cost is attributed to the need for rigorous screening, pasteurization, and freezing, making it labor-intensive and costly. However, researchers are exploring more cost-effective and convenient methods of preserving breast milk. Dr. Blanca Aguilar-Uscanga from the University of Guadalajara in Mexico has developed a spray-drying technique to turn breast milk into powder, offering a cheaper and room-temperature-storable alternative to traditional freezing. While some experts are intrigued by this method, established milk banks remain cautious, as they already have effective protocols in place for preserving breast milk. Aguilar-Uscanga's spray-dried breast milk is currently undergoing testing in select hospitals in Guadalajara, Mexico.