Quality assessment of strawberries packed with perforated polypropylene punnets during cold storage

Strawberries stored in polypropylene packages with different perforation surfaces were maintained for three weeks at 2degreesC simulating long refrigerated transport or long cold storage. After 3 days at 2degreesC, CO2 levels inside the packages were in the range of 1.5-2.6%, while O-2 contents were 17.8-18.9% for the three perforation surfaces under study. Gas levels remained practically unchanged for one week and then changed slowly such that at day 21 they were 7.2-8.8% and 13.6-14.9% for CO2 and O-2, respectively. There was a suitable fruit quality maintenance during the first 10 days at 2degreesC. After this period of time, there was an increased risk of fruit quality impairment, with an increasing marketable fruit loss and off-flavors development, and a slight decrease of sugar and organic acids content. There were practically no differences among the three microperforated packages studied in terms of fruit quality during this recommended 10-day period at 2degreesC with low levels of marketable fruit loss, no signal of Botrytis infection, and only a slight decrease in sucrose content. Comparison with control fruits during the first 10 days at 2degreesC showed practically no differences except for this microperforated packaging system being associated to lower anthocyanin content in the fruits.