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Delays in initiating the cooling of freshly harvested `Chandler' strawberries (Fragaria ×ananassa) were compared with prompt cooling to determine how such handling affected development of postharvest decays during subsequent storage and marketing. Strawberries at the three-quarter to full red ripeness stages were harvested four times between mid-June and late July, inoculated with Botrytis cinerea or Rhizopus stolonifer and then handled to simulate prompt or delayed precooling prior to storage. This was done by incubating fruit at 35 °C (95.0 °F) and 70% to 80% relative humidity (RH) for 1 or 6 hours. The fruit were then forced-air cooled to 5 °C (41.0 °F) in 1 hour and stored for 7 days at 2 °C (35.6 °F) and 85% to 95% RH, plus displayed in a simulated market at 20 °C (68.0 °F) and 85% RH for 1 day. Decay incidence increased as the season progressed. For non-inoculated fruit, prompt cooling reduced the incidence of decay by an average of 25% and the decay severity by ∼24%. With inoculated fruit, prompt cooling resulted in 15% and 29% decreases in the incidence and severity, respectively, of rhizopus rot compared to delayed cooling, and 5% and 22% decreases in the incidence and severity, respectively, of botrytis rot. Overall, the incidence of botrytis and rhizopus fruit rot averaged 60% and 85% in the prompt and delayed cooling treatments, respectively. Although prompt cooling is important for minimizing postharvest decay of strawberries, temperature management alone may not sufficiently control postharvest decay when decay pressure is high.

`Chandler' strawberries (Fragaria ×ananassa Duch.) harvested three-quarter colored or fully red were stored in air or a controlled atmosphere (CA) of 5% O₂ + 15% CO₂ at 4 or 10 °C to evaluate the influence of fruit maturity and storage temperature on the response to CA. Quality evaluations were made after 1 and 2 weeks in air or CA, and also after 1 and 2 weeks in air or CA plus 1 day in air at 20 °C. By 2 weeks, strawberries of both maturities stored in air at 10 °C were decayed, however, strawberries stored in CA at 4 or 10 °C or air at 4 °C had no decay even after 2 weeks plus 1 day at 20 °C. Three-quarter colored fruit stored in either air or CA remained firmer, lighter (higher L^* value) and purer red (higher hue and chroma values) than fully red fruit, with the most pronounced effect being on CA-stored fruit at 4 °C. CA was more effective than air storage in maintaining initial anthocyanin and soluble solids contents (SSC) of three-quarter colored fruit and fruit stored at 10 °C. Strawberries harvested three-quarter colored maintained initial hue and chroma values for 2 weeks in CA at 4 °C, becoming fully red only when transferred to air at 20 °C. Although three-quarter colored fruit darkened and softened in 10 °C storage, the CA-stored fruit remained lighter colored and as firm as the at-harvest values of fully red fruit. After 1 or 2 weeks in CA at either 4 or 10 °C plus 1 day at 20 °C, three-quarter colored fruit also had similar SSC levels but lower total anthocyanin contents than the initial levels in fully red fruit. CA maintained better strawberry quality than air storage even at an above optimum storage temperature of 10 °C, but CA was more effective at the lower temperature of 4 °C. Three-quarter colored fruit responded better to CA than fully red fruit, maintaining better appearance, firmness, and color over 2 weeks storage, while achieving similar acidity and SSC with minimal decay development.