In this study, four prebiotics including inulin, fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), and yeast β-glucan were added singly (inulin) or in different combinations (inulin + FOS + GOS and inulin + FOS + GOS + yeast β-glucan) to fermented milk containing Bifidobacterium animalis subsp. lactis PB200. The titratable acidity, pH, whey syneresis and total viable count of the fermented milk were measured during storage periods. Moreover, the rheological and textural properties were measured. The aim was to clarify the effect of different prebiotic combinations on the yogurt system in order to obtain the optimal probiotic combination. Compared with the control group with no prebiotic added, the addition of prebiotics significantly delayed the post-acidification, and promoted the growth of B. animalis subsp. lactis PB200. Besides, the titratable acidity of fermented milk added with inulin, FOS, GOS and β-glucan was the lowest , and the titratable acidity increased slowly and whey syneresis was less with the extension of storage time. The addition of all four prebiotics could maintain a higher viable count of B. animalis subsp. lactis PB200. The results of rheological and textural analysis showed that yogurt added with all four prebiotics had higher gel strength, hardness, cohesiveness, gumminess, adhesiveness and springiness, showing better texture. In summary, the addition of inulin, FOS, GOS and β-glucan resulted in better quality of probiotic fermented milk with B. animalis subsp. lactis PB200.

The fat in breast milk exists in the form of fat globules, which are enveloped by a unique biophysical membrane called the milk fat globule membrane. The absence of fat globules will affect the structure and stability of fat droplets, which will in turn affect lipid digestion and absorption. In an effort to make the nutritional composition of milk powder approximate as closely as possible to that of breast milk, an extensive literature has developed concerning the fat globule membrane of cow’s milk, goat’s milk and other milks both domestically and internationally. With the aim of providing a reference for the resource development and application of milk fat globule membrane resources, this article reviews recent progress in understanding the composition of the milk fat globule membrane as well as the factors affecting the structure and functional characteristics of the milk fat globule membrane such as lactation stages, feeding regimes and milk sources as well as separation, thermal processing, homogenization and non-thermal processing, and it summarizes recent advances in breast milk fat globule membrane simulation and its application in infant formula and milk products for middle-aged and elderly people.

This study investigated the optimization of formulations for dairy beverage supplemented with an extruded mixture of Tremella funciformis and five grains using one-factor-at-a-time and orthogonal array design methods. The sensory evaluation score and stability of the beverage were evaluated as a function of the amount of the extruded product, sieve mesh size used on the powdered extrudate and the amount of the composite stabilizer. Changes in the rheological properties and particle size distribution of the beverage during 7 days of storage at 4, 25 and 37 ℃ were measured by a rheometer and a particle size analyzer, respectively. The optimum process conditions were determined as follows: adding extrudate at 5% and the composite stabilizer at 0.4% and sieving the extrudate through a 160-mesh sieve. The sensory evaluation score and stability of the beverage produced under the optimized conditions were (90.14 ± 0.32) points and (92.27 ± 0.07)%, respectively. After storage at 4, 25 and 37 ℃, the beverage was characterized as a pseudoplastic fluid in static rheology and as a weak gel in dynamic rheology. After storage at 4 ℃, the viscosity coefficient and particle size distribution were similar to those before storage. To maintain its taste and shelf life (up to 180 days), the beverage should be stored at 4 ℃, and cold chain distribution is recommended for it.