the blueberries during storage (Fig. 3) and therefore the rise of SSC in the fruit. Because of the lack of slots in the PLA
containers, this increase in SSC was not observed in the fruit packed in these containers. At 10 C, the SSC was relatively
constant during storage. However, SSC decreased by 5% when the containers were stored at 23 C. This slight decline was because of the increase in the respiration rate of the fruit and therefore an enhanced consumption of soluble solids as respiration substrate. As mentioned earlier, the respiration rates of berries are directly related to storage temperature. Blueberries stored at 10 and 20 C have respiration rates of 23–35 and 52–87 mg CO2/kg h, respectively (http://usna.usda.gov/hb66/039blueberry.pdf). Mathooko (1996) suggested that enhancement of respiratory activity in fruits may result from an activation of enzymes at increasing temperature. Silva (1998) reported that low CO2 levels can reduce the rate at which sugars are utilized. Therefore, it can be speculated that a lesser amount of soluble solids was consumed because of the almost 4% CO2 in the PLA containers (Fig. 2). Rosenfeld et al. (1999) also reported that the SSC is affected by temperature and headspace composition. The lower the temperature, the higher the SSC.