Pasteurization of human milk by a benchtop High_Temperature Short_Time device

Non-traditional pasteurization technologies have been tested on human milk to ensure microbial reductions, and to minimize undesired biochemical and nutritional changes. We designed and tested a new small-scale continuous-flow High-Temperature Short-Time (HTST) pasteurizer (72 °C, 15 s), to assess its efficacy and to characterize the nutritional quality of the pasteurized human milk. Efficacy of the HTST device was assessed through challenge tests on inoculated Listeria monocytogenes, Staphylococcus aureus, Chronobacter sakazakii, as well as on the eradicating efficiency on raw human milk bacteria. Qualitative changes after HTST and standard Holder pasteurization were determined by analysis of secretory IgAs (sIgAs) content, reducing and non-reducing protein profile, lysozyme and bile salt stimulated lipase (BSSL) activities.: No pathogen, or bacterial growth were detected after HTST pasteurization conducted with the new instrument. Changes in the overall protein profile were observed in the milk pasteurized according both the processes. The sIgAs content and BSSL activity resulted to be significantly higher in the milk pasteurized with the new device than in the same milk treated with standard Holder pasteurization. The new HTST apparatus can effectively pasteurize human milk with a better retention of sIgas content and BSSL activity, providing compliance to human milk banking safety requirements.