Mechanism study on removal of browning pigment from high temperature sterilized lotus rhizome juice by lactic acid bacteria fermentation

Lactic acid bacteria fermentation significantly enhances the color quality of fruit and vegetable juices and delays non-enzymatic browning. Nevertheless, the underlying mechanisms had rarely been reported and the existing ones were only relatively superficial studies from the perspective of browning substrates. Therefore, the mechanism of lactic acid bacteria fermentation mitigating the browning of lotus rhizome juice was investigated from the perspective of browning product removal in this research. Results showed lactic acid bacteria improved the color of lotus rhizome juice by adsorbing browning pigment with 53.42 %. Peptidoglycan was the key site for pigment adsorption, with this capability being intricately linked to its composition and structure. Electrostatic and hydrophobic forces were involved in browning pigment adsorption. Notably, cell viability was not a factor that affected pigment adsorption. In the future, inactivated lactic acid bacteria can be widely used as biosorbents to enhance the color of unfermented food.