Free glycerol kit

The bacterial culture media for the fermentation were prepared in two ways. The first was to culture L. gasseri and L. plantarum in MRS medium (69966, Sigma-Aldrich, St. Louis, MO, USA) for 48 h at 37 °C and then use both the bacteria and the culture medium (strains with culture medium). The second was to use only the medium from which the bacteria were removed through centrifugation (4 °C, 8935× g, 10 min) after the same 48 h of culturing (only culture medium). For fermentation, 2 g of the strains with the culture medium and only the culture medium were mixed with 20 g of HIO, and then fermented in a shaking incubator (37 °C to 200 rpm). Fermentation was carried out in a glass tube for 0–35 d, and after completion, the oil and layered medium were removed with a micropipette. The HIO after fermentation was evaluated for the content of free glycerol and free fatty acids, which are products of lipid decomposition. Measurements were performed according to the protocols enclosed in the Free Glycerol Kit (ab65337, abcam, Cambridge, UK) and Free Fatty Acid Quantitation Kit (MAK044, Sigma-Aldrich, St. Louis, MO, USA), respectively.