Whey Protein Concentrate, Pullulan, and Trehalose as Thermal Protective Agents for Increasing Viability of Lactobacillus plantarum Starter by Spray Drying

Improved viability of trehalose on Lactobacillus plantarum embedded with whey protein concentrate/pullulan in simulated gastrointestinal conditions and its application in acid juice

“…A texture analyzer (TA-XTplus, Stable Micro Systems Corporation, UK) equipped with a cylindrical probe (TA/0.5) was used to analyze the texture properties of hydrogels according to Sun et al [16]. The hydrogel, a cylinder with a height of 3 cm and a diameter of 2 cm, was tested by two-compression mode with an interval of 5 s, trigger force of 5 g, test speed of 1 mm/s, and compression deformation was 30% of the sample height.…”

“…The maximum survival rate of 91.58% for L. plantarum occurred at 5.0% TRE, which was significantly higher than other concentrations, especially the group without TRE (83.4%). The survival rate decreased at 6.0% TRE, which may be due to the increase of osmotic pressure caused by the overconcentration of extracellular D surroundings, leading to injury to L. plantarum [16]. Besides, excess TRE hastened the accumulation of protein in cells, developing an intense glassy state, which influenced the release of L. plantarum after rehydration [28].…”

“…Whey protein concentrate (WPC) alone [14] or in combination with pullulan (PUL) [15] has been used as the wall materials of microcapsules for many years. It was reported that WPC/PUL hydrogel was prepared using WPC and PUL by heating to protect L. plantarum and L. rhamnosus GG (LGG) [16][17]. The number of live LGG in WPC/PUL microcapsule was 7.24 (Log CFU/g) after spray drying, and the survival rate was 44.43%, which was higher than that of free cells after cultivation in SGJ for 4 h [17].…”

The promotion mechanism of prebiotics for probiotics: A review

“…In the preparation of probiotics, they are usually dried into powder by freeze-drying or spray drying. However, adverse environmental conditions, such as acid, heat, pressure, and oxygen, can also cause a significant decline in the cell viability of probiotics ( 170 ).…”

“…The process of spray drying cannot avoid of drying and dehydrating at high temperatures, which will destroy the structure of proteins and nucleic acids, and disrupt the connection between monomer units, largely affecting the viability of probiotics. Therefore, protective agents play a crucial role in protecting probiotics from adverse conditions and in storing them for long periods after drying ( 170 ).…”