Solid-State Fermentation Using <i>Bacillus licheniformis</i>-Driven Changes in Composition, Viability and In Vitro Protein Digestibility of Oilseed Cakes

Abstract

The solid-state fermentation (SSF) efficiency of Bacillus licheniformis ATCC 21424 (BL) on various agro-industrial by-products such as oilseed cakes [hemp (HSC), pumpkin (PSC), and flaxseed (FSC)] was evaluated by examining the nutritional composition, reducing sugars, and in vitro protein digestibility (IVPD) for use in animal nutrition. SSF significantly decreased crude protein, along with changes in the total carbohydrates (p p > 0.05). After fermentation, neutral detergent fiber (NDF) and acid detergent fiber (ADF) significantly increased for HSC and FSC (p p p < 0.05). Through gastro-intestinal simulation, the bacterial survivability rate accounted for 90.2%, 101.5%, and 85.72% for HSC, PSC, and FSC. Additionally, IVPD showed significant improvements compared to untreated samples, reaching levels of up to 65.67%, 58.94%, and 80.16% for HSC, PSC, and FSC, respectively. This research demonstrates the advantages of oilseed cake bioprocessing by SSF as an effective approach in yielding valuable products with probiotic and nutritional properties suitable for incorporation into animal feed.

Keywords

• solid-state fermentation
• Bacillus
• proximate composition
• digestibility
• IVPD
• fatty acid profile