INFLUENCE OF DILUTION, TIME, AND TEMPERATURE AFTER PREPARATION ON THE OSMOLALITY OF INFANT FORMULAS GIVEN TO NEWBORNS

ABSTRACT Objective: To analyze the influence of dilution, time, and temperature after preparation on the osmolality of infant formulas given to newborns (NBs). Methods: Experimental and descriptive study with samples of different neonatal formulas to verify the osmolality of the milk according to dilution, time, and temperature after preparation. We analyzed seven neonatal formulas in the following times after preparation: immediately (up to 5 minutes); 20 and 40 minutes; every hour up to 8 hours; and 12 and 24 hours. The samples were evaluated at room temperature and after refrigeration. Osmolality curves were designed with the mean of triplicate samples of each milk sample. The digital Osmometer A+, model 3320, from Advanced Instruments measured the osmolality. Results: The time and temperature at which the milk was subjected after preparation did not cause the osmolality to exceed its safety cut-off point at a 1:30 dilution in any of the types of milk analyzed. At a 1:25 dilution, the formula with prebiotics in its composition went over the limit after 4 hours. Conclusions: The milk tested did not exceed the cut-off point of 450 mOsm/kg (approximately 400 mOsm/L), indicated as safe by the American Academy of Pediatrics (AAP) at a dilution recommended by manufacturers. It is important to know the factors that may or may not contribute to the rise of osmolality, in order to establish safe and quality practices for NBs, following protocols based on scientific evidence.

摘要
目的：分析配制后稀释度、放置时间与温度对新生儿（Newborns, NBs）配方奶渗透压的影响。
方法：本研究为实验描述性研究，选取多款新生儿配方奶样本，探究不同稀释条件、配制后放置时间与温度下奶液的渗透压水平。本次共分析7款新生儿配方奶，检测的配制后时间节点包括：即刻（≤5分钟）、20分钟、40分钟、每小时直至8小时，以及12小时与24小时。样本分别在室温及冷藏条件下进行评估。以每份奶样的三次重复检测均值绘制渗透压曲线，采用Advanced Instruments公司生产的型号3320型数字渗透压仪（Osmometer A+）完成渗透压测定。
结果：在1:30的稀释比例下，所有受试配方奶的渗透压均未超出安全阈值，无论配制后的放置时间与环境温度如何。在1:25的稀释比例下，添加益生元的配方奶在配制后4小时即超出渗透压安全限值。
结论：按照生产商推荐的稀释比例配制时，本次受试的配方奶渗透压均未超出美国儿科学会（American Academy of Pediatrics, AAP）认定的安全阈值450 mOsm/kg（约400 mOsm/L）。了解可能影响渗透压升高的相关因素，有助于基于科学证据制定针对新生儿的安全、优质喂养操作规范，保障新生儿的喂养安全与质量。