Effect of exogenous DPD on fermentation characteristics and flavour formation of Lactiplantibacillus plantarum HRB1 in vitro and in a dry sausage model: Insights from the quorum sensing system
Jiasheng Lu, Yumeng Sui, Xin Liu, Jiawang Wang, Jiatong Li, Baohua Kong, Qian Chen, Weiwei Yang
Abstract
The present study aimed to investigate the impact of 4,5-dihydroxy-2,3-pentanedione (DPD; 0, 300, 600, and 900 nmol/L), a crucial precursor in the LuxS/ AI-2 quorum sensing system, on flavour formation by Lactiplantibacillus plantarum HRB1 both in vitro and dry-sausage model. Firstly, L. plantarum HRB1 was selected from 18 strains of lactic acid bacteria due to its superior AI-2 and protease activity. In vitro , DPD significantly increased the activity of the AI-2 and the protease activity of L. plantarum HRB1. In the fermented dry-sausage, free amino acid content was significantly higher in the treatment with 600 nmol/L DPD compared to the other treatments. Notably, the dry sausage treated with 600 nmol/L DPD exhibited the highest concentrations of aldehydes (558.50 μg/kg), ketones (192.41 μg/kg), alcohols (1175.56 μg/kg), acids (202.27 μg/kg), esters (1504.48 μg/kg), and terpenes (1319.82 μg/kg). Sensory analysis revealed that the dry sausage treated with 600 nmol/L DPD had the most pronounced fermented and fatty odour. These results suggest that 600 nmol/L DPD enhances the flavour formation of L. plantarum HRB1. This research provides a theoretical foundation for utilizing the LuxS /AI-2 QS to optimize microbial fermentation processes and improve fermented food quality, especially flavour. • Lactiplantibacillus plantarum HRB1 exhibited high autoinducer-2 (AI-2) activity. • Exogenous DPD promoted AI-2 production and protease activity of L. plantarum HRB1. • Exogenous DPD promoted flavour formation by L. plantarum HRB1. • Dry sausages treated with 600 nM DPD had the highest free amino acid content. • Dry sausages treated with 600 nM DPD had the highest volatile compound content.