Soymilk modification by immobilized bacteria in a soft elastic tubular reactor's wall

Soybean products are an important food source, but there are issues related to their nutrition and waste accumulation. We developed an immobilized mixed strains system on agitated flasks and a soft elastic tubular reactor (SETR) to obtain a whole soymilk fermented product (without okara and hull removal). Our findings indicate that the mix of Lactobacillus plantarum/Bacillus subtilis subsp. Natto, immobilized in gellan/xanthan/PU foam mat lining the reactor, resulted in a product with a high protein hydrolysis degree (20%), degradation of the 7 S protein fraction, lower total reducing sugars (>70% reduction) and trypsin inhibitors (>80% reduction), and higher total phenolics (>200% increase). This is associated with lower flatulence, allergenicity, and higher nutrient availability and bioactivity. The SETR mixing profile, combined with the immobilization method used in this work, resulted in a stable continuous process and should be better explored as a bioprocess option for non-traditional media. •L. plantarum/B. natto mixed strain process modified a whole soymilk -like product.•In 4- or 8-h the product composition and functionalities are changed.•TRS are low and 7 S protein fraction was not detectable.•Gellan/xanthan gel supported by PU foams lining the reactor wall was robust.•Repeated batch and continuous process were stable for 12 cycles.