An inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) method was established for the analysis of 26 inorganic elements in dairy products. Under MS/MS conditions, the 26 elements were detected in the no gas, collision gas (He) or reaction gas (H2, O2, NH3/He) mode and the optimal mode was selected for each of the elements. The results showed that calibration curve with good linearity was obtained for each element in the appropriate detection mode with a correlation coefficient greater than 0.999 0. The detection limits of the 26 inorganic elements ranged from 0.000 033 61 to 0.043 71 mg/kg. The spiked recoveries were between 95.50% and 104.21%, with a relative standard deviation (RSD) ≤ 3.94% (n = 11). The contents of Na, Mg, K, Ca, P, Fe and Zn were higher and the contents of the heavy metal elements Cr, As, Cd and Pb were lower in six kinds of dairy products, all of which were lower than the national standard limits. The method was characterized by simple pretreatment, high sensitivity, low limit of detection and high accuracy and could be used for the detection of inorganic elements in dairy products.

This research investigated the effects of reconstitution pH value and temperature, storage duration, sunlight exposure and reheating on the contents of vitamin B1 and vitamin D in six different kinds of formula foods for special medical purposes sold on the market. The results showed that the vitamin B1 content decreased with increasing reconstitution pH value and temperature and storage time, but was little affected by reheating. The vitamin D content decreased with storage time in sunlight. pH value and reheating had little effect on the content of vitamin D. The optimum conditions for ensuring the highest utilization ratio of vitamin B1 and vitamin D in formula foods for special medical purposes were reconstitution in acidic water (pH < 7) at 40–60 ℃, storage in darkness and preferably use immediately after reconstitution.

Miroecologics have a variety of functions such as regulating human intestinal microecology, immune enhancement, antitumor, anti-aging, etc and are important elements of functional dairy products. Application of probiotics in dairy products has very important significance in enriching the functions of dairy products, guiding the healthy diet and promoting the development of the dairy industry. Research and development of dairy products rich in probiotics, prebiotics and/or synbiotics will become the dominant direction of the development of dairy products. This paper introduces recent applications of microecologics in dairy products with emphasis on key technologies.