Biopreservation Potential of Shimeji (Hypsizygus sp.) Mushroom Fermented with Bifidobacterium sp. InaCC B723

Abstract

Nowadays, mushrooms are widely consumed as a source of functional food and health, including the shimeji (Hypsizygus sp) mushroom. Fresh shimeji is highly perishable, mainly due to its high-water content, high respiration rate, and the presence of microflora. The objective of this research was to examine the potential of Bifidobacterium sp. as a starter for fermentation and bio preservation of Hypsizygus sp. In this study, Hypsizygus sp. was fermented with addition of Bifidobacterium sp. (10⁷ CFU/ml), continued with incubation in room temperature 25±2 ̊C for 18 days. Fermented samples were then analyzed for the number of microbial populations including lactic acid bacteria (LAB), yeast, and Enterobacteriaceae using Total Plate Count; chemical quality of pH, lactic acid using titration, nitrite using spectrophotometry, and volatile compounds using GC-MS. During fermentation, the LAB population increased rapidly until it reached its peak population on the 3^rd day. The rapid growth of LAB was followed by an increase in lactic acid content and a decrease in pH. Organic acids can control the growth of other microorganisms such as yeasts, molds, and Enterobacteriaceae while preventing the damage and decay of mushrooms. GC-MS analysis of fermented mushroom extract exhibited major bioactive compounds of butanoic acid (14,25%), Hydroperoxide, 1-methylpentyl (10,01%), and n-hexadecanoid acid (9,756%). This research was the first report on the use of Bifidobacterium sp. for Hypsizygus sp. fermentation, with potential to be applied as a bio-preservation method of edible mushrooms with enhanced characteristics which can be applied to the wider community.