MAINTAINING THE QUALITY OF STRAWBERRIES BY COMBINED EFFECT OF AQUEOUS CHLORINE DIOXIDE WITH MODIFIED ATMOSPHERE PACKAGING

ABSTRACT This study evaluated the efficiency of various concentrations (3, 6 and 9 ppm) of ClO2 and modified atmosphere packaging (MAP). Quality criteria of fresh strawberries were analyzed during storage. Highest CO2 and lowest O2 levels were observed inside the package for the control (without ClO2) group. ClO2 treatments were effective in retaining pH and titratable acidity. After 25 days, ClO2 groups exhibited low conductivity (3.4–3.5 µS/cm) and high L* values, around 30, compared with the control group. ClO2 was effective in maintaining the stability of anthocyanin. At day 6, the 9 ppm group had the highest a* value (30.06). Firmness values were in the range of 280–300 g for the ClO2-treated group and around 100 g for the control group at the end of storage. Fourier transform near-infrared spectra gave comprehensive information about the water and sugar contents of the strawberries. The overall results indicated that ClO2 treatment and MAP had significant effect on the postharvest quality of fresh strawberries. PRACTICAL APPLICATIONS Strawberries are highly perishable fruits due to high respiration rate, and require protection during storage. The present study demonstrated that combination of various ClO2 concentrations and modified atmosphere packaging technologies is capable of maintaining the shelf life of fresh strawberries and has been suggested as an interesting alternative to traditional sanitizers. Also, Fourier transform near-infrared measurements provided good estimates of the internal quality indices of the fresh strawberries.