L-valine， as one of the essential amino acids， has important applications in many fermented food ingredients. Timely understanding and monitoring its fermentation process is beneficial to improve the quality of L-valine products. In this paper， a new method for monitoring the production process of fermented food ingredients was developed. And the near infrared model of the main raw materials and products was established by analyzing the raw materials and products of fermentation. On this basis， combined with the metabolic flux model， the distribution and variation of metabolic flux in cells under different fermentation conditions can be rapidly analyzed monitor the parameters of the fermentation process in real time. The method can simultaneously detect the components quickly and accurately， thus making up for the shortcomings and shortcomings of the traditional detection methods； Meanwhile the method can quickly and accurately obtain the metabolic flow distribution in the cell during fermentation， so as to help control the fermentation process， monitoring the fermentation process parameters for real-time. It provides a theoretical basis for the automatic control of fermentation process， and provides a method for monitoring the production process of fermented food ingredients.