Abstract: Critical flavor of ultra-high temperature sterilized (UHT) milk is an important factor affecting the product quality and consumer choice. At the same time, the development of new formula products also poses a greater challenge to quality control and flavor prediction. In order to study the critical flavor changes of UHT milk under storage temperature and light, headspace solid phase microextraction (SPME) -gas chromatography-mass spectrometry (GC-MS) was used to detect the volatile flavor components of the product. Combined with descriptive sensory evaluation, orthogonal partial least squares discriminant analysis and entropy weight method were used to determine the corresponding relationship between critical flavor and critical substance. The effects of temperature and light flux on the flavor changes of different formulations of UHT milk were analyzed, and a critical flavor integrated analysis model of UHT milk based on the effects of initial unsaturated fatty acid content, temperature and light flux was established. The research results provide support for the quality control of different formulations of UHT milk.

Key words: Ultra-high temperature sterilized milk, Critical flavor, Prediction model, Luminous flux, Entropy weight method