Soluble solids (SS) content
As can be seen in Figure 3, the SS content for the control treatment does not change from the beginning to 30 days of storage, maintaining 10.9 ± 1.2 ºBrix. This value was found by Coelho et al. (2010) in immature fruits. According to this author, the SS content remained unchanged during the fruits ripening since they were harvested at adequate physiological stage. According to Azzolini (2002), the SS content depends on the maturity stage, and it generally increases progressively during the ripening process due to the hydrolysis of polysaccharides to maintain the respiration rate.
After 30 days of storage in controlled atmosphere, it was verified that, considering the atmospheres with lower CO2 level, the SS content was higher at atmosphere with 1% O2 and 0.03% CO2 (Figure 3). However, it did not differ from the fruits stored at 5% O2 and 15% CO2.
The SS content decreased intensively in all atmosphere treatments in the fruits evaluated after removal from the atmosphere chamber and storage during 9 days under refrigeration; excepted for the fruits stored at 5% O2 and 15% CO2 (Figure 3). In this atmosphere, it was observed a tendency of higher values compared to those of fruits stored at 1% O2 and 5% O2 with traces of CO2, and the value remained at the same level of that observed for the control sample after 30 days of storage. This indicates that the application of higher concentration of CO2 combined with low levels of oxygen reduced the decrease of SS after removal of atmospheres.