UHT Milk: Supply Chain Based Shelf Life Assessment and Risk Mitigation

Transportation and storage conditions in the perishable food supply chain play a vital role in product shelf life. This study focuses on UHT milk, a variant of milk that has a shelf life of up to 12 months in ideal conditions. However, poor transportation and storage practices can diminish its shelf life and result in quality losses resulting from milk spoilage. UHT milk literature focuses on chemical and physical analysis of changes in milk. There have been limited number of studies that characterize supply chain effects on the shelf life of milk and other perishable products.

This study analyzes supply chain effects on UHT milk shelf life using four methods: 1. Accelerated shelf life study of UHT milk spoilage factors, 2. Physical simulations of supply chain scenarios, 3. Predictive model for UHT milk degradation, and 4. Supply chain planning software for managers. The accelerated shelf life study quantifies changes in UHT milk using color (L*, a* and b*), enzymatic activity (lipase and protease) and pH at varying temperatures (70°F, 80°F, 90°F and 100°F) and constant relative humidity (60%) over a period of 88 days. It is observed that a* color value provided the best correlation coefficient to quantify milk degradation. Physical simulations are designed based on actual supply chain conditions of UHT milk. The a* color value for UHT milk samples is measured at the start and end of each scenario. An iterative piecewise linear model predicts the end value of a* based on parameters from the accelerated shelf life analysis. The accuracy of the predictive model is 88%. A graphical user interface (GUI) software is designed to simplify planning the supply chain timeline of the UHT milk using the predictive model.