Kinetics of freshly squeezed orange juice quality changes during ozone processing

J Agric Food Chem. 2008 Aug 13;56(15):6416-22. doi: 10.1021/jf800515e. Epub 2008 Jul 15.

Abstract

Freshly squeezed orange juice samples were ozonated with control variables of gas flow rate (0-0.25 L min (-1)), ozone concentration (0.6-10.0%w/w), and treatment time (0-10 min). Effects of ozone processing variables on orange juice quality parameters of pH, degrees Brix, titratable acidity (TA), cloud value, nonenzymatic browning (NEB), color values ( L*, a*, and b*), and ascorbic acid content were determined. No significant changes in pH, degrees Brix, TA, cloud value, and NEB ( p < 0.05) were found. L*, a*, and b* color values were significantly affected by gas flow rate, ozone concentration, and treatment time. The changes in lightness ( L*) values and total color difference (TCD) values were fitted well to zero-order kinetics, whereas a*, b*, and ascorbic acid degradation followed first-order kinetics. The rate constants for a*, b*, and TCD were linearly correlated with ozone concentration ( R (2) = 0.88-0.99), whereas the rate constants for L* and ascorbic acid were exponentially correlated ( R (2) = 0.94-0.98).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascorbic Acid / analysis
  • Ascorbic Acid / chemistry
  • Beverages / analysis*
  • Citrus sinensis / chemistry*
  • Food Handling / methods*
  • Fruit / chemistry*
  • Hydrogen-Ion Concentration
  • Kinetics
  • Maillard Reaction
  • Ozone*
  • Quality Control

Substances

  • Ozone
  • Ascorbic Acid