The influence of different controlled atmosphere storage conditions on the storability and quality of blueberries cv. ‘Bluecrop’

摘要

Blueberries cv. 'Bluecrop' were harvested andstored on the same day at 0 :!: 0.5 °C on various controlledatmosphere (CA) conditions, which involve two oxygenconcentrations (18% and 2% 02) combined with fourC02-concentrations (6%, 12%, 18%, and 24%). Coldstorage in normal air represented 'control' treatment.After seven weeks in store, it was obvious that increasingC02-concentration led to a significat lower decay incidence.Furthermore, lowering 02-concentration, in combinationwith 12% and 18% CO2, led to a further reduction indecay incidence. Moderate CO2-concentration to 6% wasof no advantage compared to cold-stored fruits. However,it was also obvious that increasing C02-concentration, inparticular above 12%, accelerated the softening of berries,compared to berries stored under control or 6% C02 +2% 02. Changes and differences in the total soluble solidsvalues ( -sugar content) were non-significant betweenthe treatments, whereas significant differences in thetitritable acidity (TA) were observed. At harvest time,the TA value was already high, and increased steadily,in particular with berries stored under m()derate (6-12%)CO2-concentrations. Differences in the external quality,which was evaluated by a taste panel, between various CAstorageconditions were also non-significant, whereas majorsignificant differences were assessed in respect to internalquality. All storage conditions with 18% and 24% C02,irrespective of 02-concentration, received bad evaluation,mainly due to off-flavour. In contrast, berries stored under12% C02, but without lowering 02-concentration, wereperceived as good, whereas berries stored under the sameC02-concentration, but with a lowered 02-concentration,were scored as fruits of medium quality. In conclusion, it ispossible to store blueberries cv. .Bluecrop' up to six weeksunder 12% C02-concentration, but without any reduction in02-concentration, which wi1l guarantee the preservation ofthe fruit firmness, combined with low decay incidence leveland the absence of off-flavour and off-taste