Kinetics of Thiamin and Riboflavin Loss in Pasta as a Function of Constant and Variable Storage Conditions

The stability of thiamin and riboflavin in enriched pasta humidified to different water activities was measured at 25, 35, 45, and 55°C for periods of up to 1 yr. Riboflavin was shown to be extremely stable (dark reaction) whereas thiamin losses were significant. Thiamin loss increased with temperature (Q 10 of 4.5) and water activity. Predictions of thiamin loss for a square wave temperature fluctuation using steady state data were compared to actual losses found in storage for pasta held at equal alternating times at 25/45 and 25/55°C. The Hicks‐Schwimmer‐Labuza model provided an adequate method for predicting both the amount of loss and the effective temperature from steady state data.