Effects of Lactarius deliciosus on the Shelf Life and Microbial Diversity of Fat-Reduced Emulsified Sausage

Abstract

The high-fat properties and perishability of emulsified sausages have become a challenge in the food processing field, and the development of an emulsified sausage based on Lactarius deliciosus can effectively avoid these adverse effects. Therefore, this study examined the effects of different amounts of Lactarius deliciosus (0%, 1%, 2%, 4%, and 8%) on the lipid oxidation, pH, colour, total bacterial count, and microbial diversity of fat-reduced emulsified sausages during refrigerated storage at 4°C (0, 2, 7, 14, and 16 days). Results showed that adding 4% L. deliciosus was most effective in reducing fat oxidation in sausages during Days 7–16 of storage. Additionally, adding 2% and 4% L. deliciosus significantly reduced the total bacterial count of fat-reduced emulsified sausages (p < 0.05). High-throughput sequencing results showed that at the late storage (14 days), 4% L. deliciosus exerted a good inhibitory effect on the growth of the dominant bacteria Buttiauxella and Photobacterium with a reduction in relative abundance from 21.2% to 3% and from 6.4% to 0.3%, respectively, when compared to low-fat emulsified sausage with 0% L. deliciosus. Briefly, adding 4% L. deliciosus could inhibit the growth of specific microorganisms and fat oxidation in fat-reduced emulsified sausages and thus exert a positive effect on the shelf life of fat-reduced emulsified sausages. This study provides new insights into the storage stability and potential shelf life extension of fat-reduced emulsified sausages refrigerated at 4°C, which can be valuable for related meat product processing industry.