*2.4. Analytical Methods*

The various fractions and samples were analyzed for lactose, galactose, glucose, lactic acid, acetic acid and ethanol content using a UHPLC Dionex Ultimate 3000+ chromatograph (Thermofisher, Italy) equipped with a UV/Vis and RI detector. The standards and the samples, previously ultrafiltered on Centricon systems with 3 kDa cut-off, were injected in a Shodex sugar SH1011 300 × 8 mm, 6 µ column according to the following operating conditions: isocratic elution with 0.1% sulfuric acid in water at a flow rate of 0.8 mL/min; temperature: 40 ◦C; concentration range: 20–0.01 mg/mL; acquisition time 25 min [21].
