A probiotic nutraceutical based on functionalised rice bran (RB) supplemented with lingonberry (Vaccinium vitis-idaea L.) pulp (LP) at various levels (10-50 g/100 g d.w.) was developed. Prior to immobilisation of lactic acid bacteria (LAB) cells, RB-LP matrix was structured by ultrasound (US) (850 kHz; power 160 W) for 20 min at 40 °C. Xanthan gum and sodium alginate were used for the stabilisation of RB-LP matrix. Survival and fermentative activity of the immobilised LAB cells was studied by monitoring pH, cell number, antimicrobial activity, lactic acid and acetic acid production. US treatment increased by 17.5% soluble dietary fibre (SDS) contents in RB but reduced on average by 49.9% hyperoside, quercetin, quercitrin and coumaric acid contents in LP material. RB substrate supplemented with LP (20-50 g/100 g d.w.) resulted in higher antimicrobial activity against Escherichia coli, Salmonella typhimurium and Staphylococcus aureus for Lactobacillus brevis, and against Bacillus cereus and Staphylococcus aureus for Pediococcus acidilactici. RB-LP matrix stabilised with alginate-xanthan and alginate maintained 8.09-8.67 log CFU g À1 live cells of immobilised L. brevis after 7 weeks of storage at 4 °C. In the case of protection under simulated in vitro digestion conditions, RB-LP gels with sodium alginate demonstrated the highest cell survival with 4.25 CFU g À1 viable cells remaining in the product and 5.23 log CFU g À1 live cells in the digestion medium.

In this study, the effect of solid-state fermentation (SSF) with Lactobacillus sakei MI401 and Pediococcus acidilactici PA-2 strains on functional properties of extruded (130 °C; 25 rpm) corn-milling by-products (CMB) and their albumin, globulin, and prolamin fractions was evaluated in order to produce stabilized and functionalized food/feed stock. Extrusion resulted in a considerable reduction of microbial contamination of CMB by five log cycles, increased damaged starch, water-absorption capacity, and lowered protein and fat contents by 12.4% and 37%, respectively. The application of SSF for the extruded CMB have been shown to improve the water absorption, foaming, and emulsifying capacity of albumins and globulins and also increased the digestibility and free radical scavenging activity of prolamins. The essential amino acid content (EAA) in CMB and antioxidant activity of prolamins was lowered after extrusion but significantly increased after SSF. The combination of the abovementioned treatments can be confirmed as a prospective functionalization of CMB, capable of potentially enhancing its safety and improving nutritional, biochemical, and technological properties of proteins.

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