Effect of Freezing Time on Macronutrients and Energy Content of Breastmilk
Breastfeeding Medicine, 06/01/2012
García–Lara NR et al. – 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.
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.
- By 3 months from freezing with the two homogenization methods, they 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.



