**1. Introduction**

Dairy products are beneficial to human health, especially for formula-fed newborns. India and the European Union both produced around 160 Mt milk in 2016 [1]. People are very concerned about the nutritional ingredients and illegal additives of the milk products. As we all know, bovine milk includes 80% caseins (CN) and 20% whey proteins. Caseins consist of αs1-CN, β-CN, αs2-CN, and κ-CN in an approximate 4:4:1:1 weight ratio. Whey proteins mainly consist of β-lactoglobulin (β-LgA, β-LgB) and α-lactalbumin (α-Lac) in a 3:1 weight ratio [2]. The quantity of milk fraction proteins is related to the development of the baby. As many literatures reported, preservatives and artificial sweeteners may be harmful to people's health [3–5].

According to the regulation of FDA and China national food safety standard, food additives such as benzoic acid, sorbic acid, natamycin, lysozyme, saccharin sodium, and aspartame are not permitted to be added to milk powder. So, establishment of accurate and convenient methods for the analysis of these food additives in milk powder is critical to people's health.

Here, I'll introduce two works of our groups to readers: the comparison of six sample preparation methods for the analysis of four preservatives and two artificial sweeteners in milk powders [6] and two-dimensional liquid chromatography (2DLC) for determination of five major proteins and seven additives in milk powders.
