Lacticaseibacillus paracasei JY025 fortified milk powder: In vitro digestion characteristics and accelerated storage stability

To clarify the reciprocal influence between the fortified bacterial powder of Lacticaseibacillus paracasei JY025 (LBP) with milk powder matrix during the gastrointestinal digestion and storage period, the digestion characteristics and storage stability of Lacticaseibacillus paracasei JY025 fortified milk powder (LFMP) were explored in this study by the in vitro simulated digestion and the accelerated storage. The results showed that the milk powder matrix significantly improved the survival of JY025 during the simulated digestion (the highest improvement of 27%) and storage period (the highest improvement of 37%), which suggests the milk powder matrix can be an effective strategy to enhance the viability of probiotics during the digestion and storage period. Moreover, the digestion characteristics and the physicochemical properties of the milk powder matrix were changed due to the fortified LBP during the simulated digestion and storage period. The fortified LBP decreased the particle size of milk powder digest and promoted the hydrolysis of milk protein during digestion due to the effect of both maltodextrin (wall material) and bacteria. The fortified LBP also increased the particle size of milk powder matrix and decreased the Maillard reaction of milk powder matrix during the storage period, which is closely related to the storage condition.