Impact of Lactobacillus rhamnosus GG fermentation on shelf life of Volvariella volvacea paste

Abstract Paste formulations of Volvariella volvacea (VV) were developed for its shelf-life enhancement. Egg stage fruiting bodies of mushrooms were used for preparation of salted, spiced, and their fermented pastes. Fermented paste formulations were developed using inoculation with Lactobacillus rhamnosus GG at 0.5% (w/w) and incubation for 2 days at 35 ± 2 °C. The unfermented VV paste was preserved with sodium benzoate of 0.065%, while fermented formulations were kept devoid of any chemical preservative. All formulations were packed in glass jars and retort bags, and thereafter treated in boiling water bath for one hour. The spiced, fermented VV paste scored highest in sensory evaluation and maximum crude protein and moisture contents, while lowest in contents of ash, fat, crude fibre, and carbohydrates. The fermented (salted and spiced) VV pastes showed variation in pH at 4 °C. Shelf life of 56 days was observed for fermented VV paste stored in glass jars under refrigerated conditions. The antioxidant analysis revealed that DPPH radical scavenging activity of fermented paste formulations increased significantly up to 21 days followed by gradual decrease until the 56 th day, while total phenolic content of all paste formulations decreased with storage time. Hence, fermented spiced paste showed enhanced nutritive and antioxidative potential and shelf life up to 56 days.