Umami Taste and Breastfeeding in the First Months of Life

A study led by the Ecuadorian pediatrician Prof. Dr. Manoel Baldeón evaluated the concentrations of glutamate and other amino acids present in the milk of adult and adolescent mothers, aged between 14 and 27 years. One of the important details of the study was the relationship with breastfeeding duration: the longer the breastfeeding period, the higher the concentration of glutamate and, consequently, of the umami taste in breast milk. In colostrum (3 days after birth), the mean concentration was 44.44 ± 5.96 µmol/dL; in transitional milk (15 days after birth), 91.25 ± 6.45 µmol/dL; and in mature milk (3 to 4 months after birth), the concentration of glutamate increased to 120.33 ± 6.45 µmol/dL (BALDEÓN et al., 2014). After this period, glutamate levels tend to remain stable or decrease.

The importance of glutamate in breast milk has already been mentioned in several texts on this portal, demonstrating that this amino acid provides energy for the development of enterocytes (epithelial cells of the surface layer of the small and large intestine). These cells use nutrients and substances from the diet to maintain the functional integrity of the intestinal mucosa, protecting it against pathogenic microorganisms, among other functions. For these and other reasons, breastfeeding during the first 6 months of life is emphasized (BALLARD & MORROW, 2013).

Since the 1960s, studies on the identification of substances present in breast milk have grown exponentially, as its components can sustain infants for approximately six months of life (ZHANG et al., 2013). Another area of interest comes from the food industry, which seeks to produce these components on an industrial scale to formulate milk similar to this food. Therefore, amino acids have become one of the main research targets in this field (BALLARD & MORROW, 2013).

In Dr. Baldeón’s study, in addition to the increase in glutamate, there was also a rise in the concentration of conditional amino acids* such as glutamine, and essential branched-chain amino acids** (leucine, isoleucine, and valine). Glutamine is a free amino acid abundantly found in breast milk. It is converted into glutamate, which in turn is converted into α-ketoglutarate to enter the Krebs cycle and generate energy in the form of ATP (adenosine triphosphate). Branched-chain amino acids are essential for reducing protein catabolism, maintaining skeletal muscle, and supporting protein synthesis.

The authors of the cited study also discussed the relationship between maternal diet and the concentration of free amino acids, since most of the mothers were underweight. They encouraged further research in this field, as there is a growing discussion about the need for greater support to improve maternal nutrition and breastfeeding for at least the first six months of life.

* Conditional amino acids: amino acids that are produced by the body but, in certain situations, need to be obtained from the diet.
** Essential amino acids: those that body cannot produce and must obtain through food.