# Trends and Opportunities in the Dairy Industry: A2 Milk and Processing Methods
## 5 Milk Processing
### Non-Thermal Methods  
Non-thermal methods (Table 2) of milk processing have the same goal as thermal methods: extending shelf-life and ensuring microbiological safety. However, they attempt to reduce the adverse effects of elevated temperatures on milk and reduce energy consumption. Non-thermal methods make it possible to inactivate micro-organisms and enzymes with minimal impact on the nutritional value of milk and its sensory properties [73]. Their influence on the physicochemical characteristics of milk is also an important aspect that can be regulated, and this can be used in the design of new products. To be considered competitive with pasteurization, the method must meet criteria such as the same level of microbiological safety; satisfactory sensory quality and shelf-life; no significant changes in technological properties; no formation of toxic substances; the processing must be as short as possible, and maintainable; the equipment must be safe for personnel and easy to maintain in hygiene; and the cost of the process must not increase the price of the product. Nevertheless, there are regulatory, technological, and economic obstacles to overcome before they can be scaled up for industrial use. However, for example, the application of high hydrostatic pressure (HHIP) as an alternative to traditional pasteurization has already been successfully implemented [74; 75]. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Method** & **Parameters** & **Study Subject** & **Impact** & **Ref.** \\ \hline \multirow{8}{*}{Pulsed electric field (PEF)} & \multirow{8}{*}{10 kV/cm} & \multirow{8}{*}{Microbial inactivation and the physical properties of low-fat milk} & \multirow{8}{*}{4.5 log reduction in _E. coli_} \\  & & & & 4.4 log reduction in _L. brevis_ \\  & & & & 6.0 log reduction in _S. cerevisiae_ \\  & & & & Slow growth of surviving micro-organisms during storage for 15 days at 4 °C \\  & & & & No changes in pH, color, and particle-size distribution \\ \hline \multirow{8}{*}{Pulsed electric field (PEF)} & \multirow{8}{*}{Pulse width 900 s} & \multirow{8}{*}{Curd properties prepared with PEF-treated raw milk} & \multirow{8}{*}{Creater syneness and softer texture; poorer sensory experience for PEF samples} \\  & & & & \(\bullet\) PEF mixed with heat treatment improved texture and antimicrobial effect \\  & & & & No significant difference occurred during shelf-life \\ \hline \multirow{8}{*}{Pulsed electric field (PEF)} & \multirow{8}{*}{20–26 kV} & \multirow{8}{*}{Physicochemical properties of whole milk-treated PEF (fat, xanthine oxidase, and whey proteins)} & \multirow{8}{*}{PEF does not affect the final temperatures of fat melting and xanthine oxidase denaturation} \\  & & & & Denaturation of whey proteins decreased in the PEF-treated milk \\ \cline{1-1}  & & & & PEF-treated milk \\ \cline{1-1}  & & & & The formation of complexes by interaction between MFGM (milk fat globule membrane) proteins and skimmed milk proteins has been observed in PEF-treated milk \\ \hline \multirow{8}{*}{Supercritical fluid technology} & Liquid CO\({}_{2}\) & \multirow{8}{*}{Mitigating \(\beta\)-LG antigenicity by supercritical fluid extraction in whole milk powder} & \multirow{8}{*}{Reduction antigenicity of \(\beta\)-LG 54.75 \(\pm\) 2.43% at 63 °C/200 bar and 75 °C/300} \\  & & & & Temperature and pressure had a significant effect on the antigenic response of \(\beta\)-LG 54.75 \(\pm\) 2.43% at 63 °C/200 bar and 75 °C/300 \\ \cline{1-1}  & & & & The antigenic response of \(\beta\)-LG 54.75 \(\pm\) 2.43% at 63 °C/200 bar and 75 °C/300 \\ \cline{1-1}  & & & & The antigenic response of \(\beta\)-LG 54.75 \(\pm\) 2.43% at 63 °C/200 bar and 75 °C/300 \\ \cline{1-1}  & & & & Thermal treatment at 63 and 75 °C had no effect on the antigenicity \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Non-thermal milk processing methods.