Adsa Logo White Adsa Title White

Effects of pasteurization method on milk composition.

L. M. Adams


Effects of pasteurization method on milk composition.
L. M. Adams*, G. Mazon, J. H. C. Costa. University of Kentucky Lexington, KY.

From 1998 to 2003, 75% of disease outbreaks related to milk consumption occurred in states where raw milk sales are permitted (Lucey, 2015). However, illnesses associated with milk consumption totaling less than 1% of foodborne illnesses because of the pasteurization process (FDA, 2011). The main goal of pasteurization is to decrease pathogens such as Salmonella, Campylobacter, and E. coli in raw milk to a level safe for consumption (Oliver et al., 2005). There are 3 main pasteurization methods: low-temperature long time (63�C for 30 min), high-temperature short time (HTST; 72�C for 15 s), and ultra-high temperature (UHT; 135 to 150�C for 1 to 2 s). According to the International Dairy Foods Association, HTST pasteurization is the most common method used in the United States but yields milk with a lower shelf life than UHT (Bezie et al., 2019). Although UHT pasteurization extends milk shelf life, it also affects milk protein and lipid composition. In the UHT process, the extreme heat exposure denatures proteins at the tertiary and secondary structure level of whey proteins (Qi et al., 2015). Complete proteolysis occurs in the native milk plasmin and bacterial proteinases of UHT processed milk (Datta and Deeth, 2003). Moreover, the process of proteolysis can result in gelatinization of milk leaving a residue and a slight change in flavor when comparing UHT to HTST milk (Meunier-Goddik, 2016). Regarding lipids, research indicates that triglyceride levels are significantly lower in UHT compared with HTST and free fatty acid concentrations increased indicating lipolysis in UHT milk (Xu et al., 2019). Research suggests that those slight changes to milk composition might affect the acceptance of UHT milk by consumers as evidenced by a sensory panel in which HTST milk was liked slightly more than UHT (Chapman and Boor, 2001). In summary, consumer's preferences should be considered when selecting a pasteurization method for milk as it can affect the protein and lipid structure in milk consequently affecting and taste perception.

Keywords: food safety, pathogen, sensory analysis.

Biography: Originally from South Deerfield, MA Lauren is a junior studying animal sciences at the University of Kentucky. She grew up on a small farm and showed Holstein cows in 4-H. She is currently the vice-president of the UK Dairy Club and the second vice-president of Sigma Alpha. Lauren enjoys Dunkin's iced coffee and is also a big fan of the New England Patriots.