Microparticulated whey protein (at 0.5 g/100 mL) and two physically modified starches (modified barley and rice; at 0.5, 1.0 g/100 mL) were separately added as clean label ingredients to yogurt to investigate their effects on yogurt properties. The results demonstrated that all five yogurt systems had high water-holding capacity and viscosity, with the one with 1.0 g/100 mL modified barley starch having the highest water-holding capacity (70.20%) and highest viscosity (4 422 mPa·s). In addition, the particle size distribution and rheological analyses consistently showed that modified barley starch had a positive effect on the stability of yogurt. The yogurt with microparticulated whey protein was slightly but not significantly inferior to those with modified starches in all the parameters analyzed.

Streptococcus thermophilus phages pose a major threat to the production of many fermented dairy products. As new Streptococcus thermophilus phages have been continuously discovered and isolated during dairy fermentation, knowledge of the physiological characteristics and infection mechanism of Streptococcus thermophilus phages has gradually been improved. Understanding their biodiversity and determining their interaction with the host can provide a theoretical basis for the control of phages in the dairy industrial environment. This review summarizes the classification of Streptococcus thermophilus phages, the adsorption receptor and receptor binding protein of Streptococcus thermophiles and the molecular mechanisms of phage infection in order to provide useful information for the study and control of other Lactobacillus phages.

This study was an attempt to optimize the formulation of a shelf-stable fermented milk beverage using response surface methodology. The effect of whole milk powder-to-whey ratio, agar, starch, pectin, fructose and cream on the viscosity and water-holding capacity of the beverage was investigated. Whole milk powder-to-whey ratio, agar and starch were identified as the most significant factors using the Plackett-Burman design (P < 0.05). The levels of the four factors were optimized using response surface methodology with Box-Behnken design. A response surface model was developed indicating the relationship between each of the response variables and the four factors. The optimal combination obtained from the model was whole milk powder-to-whey ratio 5:1, pectin 1 g/L, starch 10 g/L and pectin 0.5 g/L.

In the manufacturing process of long shelf-life yogurt, there are many factors that may affect its quality, including pasteurization temperature and time, the homogenization degree of stirred mixtures, and filling temperature. The shelf life of yogurt can be extended by choosing a proper pasteurization temperature and time taking the product quality into account, and its texture can be improved by selecting a suitable homogenization approach, which is also beneficial to more uniformly heating yoghurt during sterilization, avoiding the collapse of the system. The recovery of yogurt viscosity can be affected by filling temperature. A proper filling temperature should be selected to reach the requirements of quality design during the manufacturing of yogurt.

This study researched the effect of homogenization and post-sterilization of shelf-stable yoghurt the morphology of modified starch granules as one of its ingredients. It was demonstrated that with increasing either homogenization temperature or pressure, more starch granules were broken down. The optimal homogenization temperature was between 60 and 63 ℃ and the optimal pressure was in the range of 15–20 MPa. The starch granules further swelled under line pressure during ultra high temperature (UHT) processing, and they gradually enlarged or even cracked with an increase in either line pressure (up to 7 bar) or reflux cycles. Increased temperature up to 80 ℃ during UHT processing resulted in breakdown of more starch granules.

As an enzyme that catalyzes the transfer of acyl groups, transglutaminase is widely used in the dairy industry. This paper briefly describes the source and catalytic mechanism of the enzyme, and further explains the mechanism of action of the enzyme on milk proteins, including casein, whey protein and milk protein products. Moreover, the application of the enzyme in the dairy industry is summarized in this paper.

In this study, the formulation of roughage-containing goat milk foam as a health product using goat milk and corn flour as main ingredients were optimized based on sensory evaluation and hardness using response surface analysis. The results showed that optimum combination of ingredients were determined as follows: ratio of corn flour to goat milk (m/V), 0.435:1; ratio of xylitol to sucrose (m/m), 0.712:1; and sucrose ester, β-cyclodextrin, citric acid and gelatin at concentration levels of 0.18%, 2.8%, 0.095 8% and 1.994%, respectively. The dairy product had a smooth appearance, evenly distributed color and refreshing taste with moderate sourness, integrating the unique aromas of goat milk and corn. Its sensory score was up to 95.48 and its hardness was 371.95 g, suitable for the vast majority of consumers. Moreover, the product showed maximum retention of the nutrients and health-protecting ingredients.

This study investigated the gelatinization properties of three types of modified starch and their application in long shelf-life yogurt. The three types of modified starch were physically modified starch (PMS), acetylated distarch phosphate (ADSP), hydroxypropyl distarch phosphate (HDSP). The results showed that the granular structure of the three kinds of starch remained intact after gelatinization. They all had strong shear resistance, and ADSP and HDSP showed stronger shear resistance and higher gelatinization temperature than PMS. Adding 2% (m/m) modified starch in long shelf-life yogurt increased its apparent viscosity, water holding capacity, viscoelasticity, yield stress, and storage stability. ADSP was better to improve the quality of long shelf-life yogurt than HDSP and PMS.