Effect of two types of ozone treatments on the quality of apple fruits

Abstract

The aim of this research was to demonstrate the effect of the ozonation process (exposure to ozone in gaseous form and rinsing in water saturated with ozone) on selected apple parameters. The scope of the study included: conducting the ozonation process under controlled conditions at a concentration of 1 ppm and exposure times of 1, 5 and 10 min (ozone in gaseous form) and 10, 15 and 30 min (ozonated water), respectively; polyphenols research; determining antiradical activity using ABTS radicals; and determining the influence of the applied method on the volatiles that give rise to odor chemicals (fragrance and aroma). In both cases, measurements were taken 24 hours after the ozonation process. Both exposure to ozone in gaseous form and washing in ozonated water did not adversely affect the appearance of the fruit. The rinsing process in ozonated water did not significantly affect the composition of the compounds responsible for the fruit’s odor. The proposed washing conditions affected the biochemical balance of the fruit. Differences in polyphenol content and antioxidant potential were noted. The mean content of polyphenols expressed as gallic acid equivalent in the control sample was determined to be 15.22 mg/100 g. In comparing the content of polyphenols with the control sample, insignificant changes in their content were noted, except for the sample with the longest ozonation. In the case of fruit washed within 30 minutes, a significant increase by 53% in antioxidant potential was noted. α- Farnesene was identified as the main component established by headspace solid-phase microextraction (HS-SPME) procedure. The proposed ozonation conditions made it possible to keep the volatile compounds influencing the sensory properties of apples unchanged.

Keywords

• apple
• ozone treatment
• antioxidant activity
• polyphenols
• essential oils
• hs-spme