Exposing milk to high temperatures (over 80 °C [176 °F]) may induce changes in the fatty acid profile if compared to fresh breast milk. To avoid the nutrient destruction, the right preparation must be respected. Evidence shows that the major changes in the overheated milk affect amino acids essential for human growth. The right heating of the milk (in particular powder formulas) must be guaranteed at a temperature not lower than 70 °C (158 °F) to prevent the proliferation of bacteria, of which the most common and feared is E. sakazakii, responsible for meningitis, septicemia and necrotizing enterocolitis. Once the packaging is open, an adequate storage of artificial milk (liquid or prepared) is pivotal: the milk must stay in a refrigerator at 4 °C (39,2 °F) until its following use, since it reduces the bacterial growth if compared with temperatures between 5 – 65 °C. (41 – 149 °F).