Spray drying is one of the most common and economical techniques typically employed in the microencapsulation of valuable food ingredients. Because most food core materials are generally hydrophobic, the feed solution to the spray dryer is normally an emulsion. The quality of microencapsulated powder is influenced by several operations and phenomena during spray drying, such as atomization and drying kinetics of the droplets into solid particles. In this review, selected research on the drying operations conducted over the last ten years as well as the properties of the produced powder is discussed. The items specifically reviewed are the spraying of uniform droplets, the breakage of emulsion droplets during atomization, simulation of drying a droplet by the reaction engineering approach, the storage stability of core ingredients, estimation of the surface-oil content, and measurement of the encapsulation state of the core ingredient in the dry particles by confocal laser scanning microscopy.

This study evaluated the possibility of numerically simulation of swallowing via moving particle simulation (MPS), defining the bolus structure as the number of particles. To verify the accuracy of the simulation, a simplified bolus falling model was studied via three-dimensional (3D) MPS. Further, we examined a simplified swallowing simulation via two-dimensional (2D) MPS to verify interactions between food properties and organ structure movement. On comparing the 3D MPS simulation and experimental results, we found that the falling time of the water bolus and configuration of the liquid-air interface corresponded to the experimental measurements and visualization images, respectively. Moreover, the calculated force on the surface was similar to the theoretical and measured values with adequate rheological and tribological properties. In the simplified 2D MPS swallowing simulation results, the food bolus exhibited different flow behaviors and deformations, thus confirming that MPS can be used for coupled simulations of food and organ structures with differing physical properties. The results suggest that MPS can be used to develop a numerical simulation of the swallowing process.

The possibility of using natural yeast for Chinese bun dough was investigated. Among several yeasts isolated from natural environments, a strain was selected for its particularly acceptable fermentability. Based on the ITS region of ribosomal DNA sequences, the strain was identified as Lachancea fermentati. This strain showed dough swelling comparable to that of conventional and characteristically produced lactic acid and isoamyl alcohol. These characteristics suggest that this strain could be used in the production of Chinese buns, which can be distinguished from conventional ones.

The apparent distribution coefficients, K_app, of some sugar alcohols to cation-exchange resins in the sodium-ion form and with divinylbenzene (DVB) contents of 2, 4, 6, and 8% were measured at 25ºC. Assuming that the binding constant, B, of ribitol to sodium ion was zero, the swelling pressures, Π, of the resins in sodium-ion form with DVB contents of 2, 4, 6, and 8％ were estimated to be 3.2, 9.4, 12.3, and 25.7 MPa, respectively. From these Π values and K_app values, the B values of each sugar alcohol were calculated. Because the B value is independent of the degree of cross-linking of the resin, the B values were obtained from the K_app for resins with different DVB contents and were averaged. Erythritol and sorbitol had almost zero binding affinity to sodium ion. Among the tested sugar alcohols, the B values were in the order of xylitol > d-arabitol, l-arabitol > mannitol.