Upcycling Lactobacillus casei culture waste into vegan cheese analogue using inulin, locust bean gum, and κ-carrageenan

The growing popularity of probiotics has led to the generation of substantial by-products. Among these, cell-free supernatant is recognized for containing beneficial postbiotics. Here, we upcycled Lactobacillus casei-free supernatant (LFS) into cheese analogues using inulin (INU), locust bean gum (LBG), and kappa-carrageenen (kCG). In this system, LBG/kCG established the primary structure, while interstitial spaces were progressively filled by INU. Despite the absence of milk proteins and fats, the cheese analogue with 35% w/w INU, 0.2% w/w LBG, and 0.8% kCG exhibited a texture and appearance resembling commercial processed cheese, as determined by texture profile analysis and dynamic small amplitude oscillatory rheometry technique. This can be attributed to the effective fat-replacing activity of INU regarding texture and rheology. Furthermore, the potassium-dominated salt composition of LFS proved advantageous for the LBG/kCG-derived structure-forming. These findings hold significant promise for upcycling probiotics wastewater into low-fat vegan cheese analogues, enriched with both prebiotics and postbiotics.