Development of a Novel Time-Temperature Integrator/Indicator (TTI) Based on the Maillard Reaction for Visual Thermal Monitoring of the Cooking Process

Development of a time-temperature indicator based on Maillard reaction for visually monitoring the freshness of mackerel

Due to the highly cost-effective and maneuverable property, Maillard reaction-based time-temperature indicators (TTIs) are considered ideal devices for temperature track and quality indication. The objective of this study was to develop a cold-sensitive TTI based on the Maillard reaction reflecting the freshness of chilled seafood. Firstly, the color evolution trends of a series of Maillard reaction-based TTIs were investigated and the xylose-lysine group represented obvious color change. Fourier transform infrared (FTIR) spectroscopy revealed the color change was associated with the formation of CN bond in melanoidin. Simultaneously, the relationships of the color change of TTI with time and temperature were established. The activation energy value (Ea) of TTI was close to that of mackerel. There existed a good relevance (R² = 0.98) between the color change of TTI and the total volatile basic nitrogen content of mackerel, suggesting this novel TTI might have the potential to monitor the freshness of mackerel.

Development of a novel Maillard reaction-based time-temperature indicator for monitoring the fluorescent AGE content in reheated foods

Dietary advanced glycation end products (AGEs) are formed via the Maillard reaction in foods, especially in reheated foods, and can cause chronic diseases. In this study, a series of Maillard reaction-based time-temperature indicators (TTIs: TTI-1, TTI-2, and TTI-3) were developed with lysine and xylose for monitoring the dynamic formation of fluorescent AGEs in reheated foods. The discoloration kinetics of Maillard reaction-based TTIs and the dynamics of fluorescent AGE formation were explored. Formulas were derived to illustrate the relationship of the color change in the TTIs with time and temperature. The activation energies (E a values) for generating the TTIs were 96.17, 87.98, and 83.55 kJ mol-1, respectively. TTI-1 was the optimal indicator for instant soy milk powder because it showed the lowest activation energy difference in this study. The results show that this series of Maillard reaction-based TTIs can be used to monitor the AGE contents in various reheated foods.