Degradation Kinetics of Anthocyanin in Blueberry Juice during Thermal Treatment

Abstract

The kinetics of anthocyanin degradation in blueberry juice during thermal treatment at 40, 50, 60, 70, and 80 degrees C were investigated in the present study. Anthocyanin degradation was analyzed up to the level of 50% retention using a pH differential method. The degradation of anthocyanin at each temperature level followed a first-order kinetic model, and the values of half-life time (t(1/2)) at temperatures of 40, 50, 60, 70, and 80 degrees C were found to be 180.5, 42.3, 25.3, 8.6, and 5.1 h, respectively. The activation energy value of the degradation of the 8.9 degrees Brix blueberry juice during heating was 80.4 kJ.mol(-1). The thermodynamic functions of activation (DeltaG, DeltaH, and DeltaS) have been determined as central to understanding blueberry degradation.

Kinetic analysis of anthocyanin degradation and polymeric colour formation in grape juice during heating

“…The determination coefficient values were higher than 0.98 indicating a good data fit to the first-order kinetic model. Our results are in agreement with those from the previous studies reporting the first-order reaction model for the thermal degradation of monomeric anthocyanins (Wang & Xu 2007;Kechinski et al 2010;Hillmann et al 2011).…”

“…Our E a value is lower than those reported for Bordo grape anthocyanins (72.74 kJ/mol) at 70-90°C (Hillmann et al 2011) and blueberry anthocyanins (80.4 kJ/mol) at 40-80°C (Kechinski et al 2010). Moreover, Wang and Xu (2007) reported a lower E a value (58.95 kJ/mol) for the degradation of blackberry anthocyanins at 60-90°C.…”

“…The t 1/2 values were determined as 10.03, 5.02, and 2.79 h at 70, 80, and 90°C, respectively. However, Hillmann et al (2011) (Kechinski et al 2010) and blackberry juice (8.8-2.9 h) at 70-90°C (Wang & Xu 2007). The dependence of the anthocyanins degradation on temperature was determined by calculating the activation energy (E a ) values from the Eq.…”

“…In order to predict the colour loss and minimise the undesired changes, the knowledge of the degradation kinetics including the reaction order, reaction rate, and activation energy is very important . The thermal degradation kinetics of anthocyanins has been studied in anthocyanin-containing juices such as from blackberry (Wang & Xu 2007), blueberry (Kechinski et al 2010), and grape (Hillmann et al 2011). However, to the best of our knowledge, no study exists on the formation kinetics of polymeric colour in anthocyanin-containing juices during heating.…”

Ricotta Cheese Whey-Fruit-Based Beverages: Pasteurization Effects on Antioxidant Composition and Color

“…Similarly to our results on the MAP content, studies on anthocyanin thermal degradation in blueberry juices have highlighted that the reaction follows a first-order kinetics process, and that the kinetic rate constant k value increases with temperature, i.e. that a greater degradation occurs at higher processing temperatures [42][43][44]. Since one of the most important reactions occurring during anthocyanin thermal degradation is polymerization, Martynenko and Chen [44] suggested the use of PC as a good indicator for anthocyanin degradation, as they found a strong negative exponential relationship between anthocyanin content and PC.…”