Journal of Agricultural and Food Chemistry vol:53 issue:8 pages:3081-3087
Detailed kinetic studies of [6S] and [6RS] 5-methyltetrahydrofolic acid (5-CH3-H(4)folate) degradation during thermal (from 60 to 90 degrees C) and high pressure/thermal (from 30 to 45 degrees C; from 200 to 700 MPa) treatments were carried out. The results confirmed that the temperature and pressure induced degradation kinetics of [6S] 5-CH3-H(4)folate were identical (within 95% confidence interval) with those of [6RS] 5-CH3-H(4)folate. Under equal processing conditions, the estimated degradation rate constants (k), activation energy (E-a), and activation volume (V-a) values of [6S] and [6RS] 5-CH3-H(4)folate were the same (95% confidence interval). The modified thermodynamic model proposed by Nguyen and co-workers (J. Agric. Food Chem. 2003, 51, 3352-3357) to describe the pressure and temperature dependence of the rate constant for folate degradation was reevaluated.