Technological and methodological aspects of the production of low- and lactose-free dairy products

The features of technologies for low- and lactose-free dairy products, which provide for special operations to hydrolyze lactose or remove it using ultra- or nanofiltration followed by hydrolysis of the residual amount, are considered. Dairy products manufactured using these technologies in different countries as well as enterprises leading in this field of production are presented. The analysis of the methods used to determine the quantitative content of residual lactose in low- and lactose-free dairy products is carried out: enzymatic, HPLC, HPAEC-PAD, amperometric biosensors, Raman spectroscopy. Due to the dairy industry's need for analytical methods for the determination of lactose in milk and dairy products with low- or lactose-free content, the AOAC Stakeholder Group on Strategic Food Analysis Methods approved Standard Performance Requirements for Biosensor Methods (SMPR®) 2018.009. These requirements were introduced for the quantitative determination of lactose in milk as well as in dairy and milk-containing products with a low or no lactose content. The biosensor method is recommended for use as the official first step of AOAC method. Additionally, it is advisable to use high performance liquid chromatography (HPLC) with mass spectrometric detection, as well as high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) as an international standard method of analysis for the determination of lactose in milk with low- or lactose-free content.