Mechanistic insights into the improvement of yeast viability by adding short-clustered maltodextrin during long-term frozen storage

The formation and growth of ice crystals are widely acknowledged to cause damage to different substances and we found short-clustered maltodextrin (SCMD) could alleviate the quality deterioration of frozen dough in previous research. But how SCMD interacts with dough components such as yeast is poorly understood. Here, we analyze the ice-recrystallization-inhibition (IRI) activity of SCMD and provide mechanistic insights into the improvement of yeast viability by adding SCMD during long-term frozen storage. SCMD had a higher IRI activity compared with DE2 maltodextrin, trehalose and glycerin at the same dosage. Through untargeted metabolomics analysis, SCMD addition proved to be enhancing lipid metabolism, regulating amino acid metabolism and energy metabolism of yeast, making yeast cells possess more similarities to the positive control with minimal freeze injury. In contrast, no significant protective effects were observed with low-concentration trehalose and glycerin. Our reports reveal the cryoprotection mechanism of SCMD from the perspective of the cellular metabolism of yeast, providing the foothold for further exploration of SCMD as a safe and efficient cryoprotectant in different fields.