Impact of non-thermal pasteurization technologies on vitamin B₁₂ content in milk

Limited studies have reported on the effect of non-thermal processing technologies on vitamin B₁₂, an essential vitamin that does not occur in many plant based foods. In this study, raw milk was treated by HHP (300 to 600 MPa, 5 min), PEF (16 kV/cm, 29 to 51 kJ/L), or UV-C (2 to 18 mJ/cm²). The results showed that PEF and HHP pasteurization preserved the initial content of B₁₂ in milk while UV-C caused 10% loss. HHP at 600 MPa (5 min) reduced the total number of microorganisms, similar to conventional pasteurization levels, without impact on vitamin B₁₂ concentration. PEF treatment at 43 kJ/L did not affect vitamin B₁₂ concentration, and provided a 0.9 log₁₀ CFU/mL reduction above the reference for pasteurization. While UV-C caused no microbial reduction with the experimental setup used, but even so, a 10% reduction in vitamin B₁₂ concentration occurred at the highest UV-C dose (18 mJ/cm²). Industrial relevance: Our study demonstrated differences in the sensitivity of vitamin B₁₂ to pressure, electric field, and UV-C light, that should be taken into account to preserve this vitamin in milk.