Leveraging Milk Permeate Fermentation to Produce Lactose-Free, Low-In-Glucose, Galactose-Rich Bioproducts: Optimizations and Applications

Previous studies highlighted Brettanomyces claussenii as a versatile yeast that produces ethanol or acetic acid from lactose, selectively metabolizes glucose while leaving behind galactose, depending on different operational conditions. This flexibility enables the production of galactose-rich bioproducts liquid dairy residues. The purpose this study is to: (i) optimize anaerobic fermentation milk permeate (MP) by B. to maximize yields galactose and minimize leftover glucose, (ii) combine optimized process with distillation drying characterize its multiple products. Response surface methodology was used for optimization. Three parameters were chosen input factors: temperature (25–35 °C), inoculation level (7.0–8.5 log cfu/mL), time (4–40 days), three metabolites responses: ethanol. optimal combination resulted in temperature, 28 °C; level, 7.6 cfu/mL; time, 33 days. Under these conditions, fermented product predicted have 63.6 g/L 4.0% v/v ethanol, 0 residual glucose. run 18 L fermentations followed freeze-drying. As result, four streams obtained characterized relevant physicochemical nutritional attributes. Our results show partial MP can be first step develop lactose-free, low-in-glucose, bioproducts, which improve value residue broaden applications food supply chain.