Optimization of packaging and storage conditions of a freeze-dried Pantoea agglomerans formulation for controlling postharvest diseases in fruit.
OBJECTIVE
This study aimed to evaluate different packaging strategies to extend the shelf life of a freeze-dried formulation of the biocontrol agent Pantoea agglomerans strain CPA-2.


RESULTS
Different materials and atmosphere packaging conditions (vacuum and air) were analysed on formulated P. agglomerans cells stored at 25, 5 and -20°C. Results showed the viability of CPA-2 cells stored at 5 or -20°C was significantly higher than when stored at 25°C. The highest viabilities were observed with the plastic material designated as Bottle 1, in nonvacuum packaging in all storage temperatures: 50% after 3 months at 25°C, 100% after 8 months at 5°C and 100 and 74% after 12 and 18 months, respectively, at -20°C; the final concentration was 10(12) CFU g(-1), a good concentration for a commercial product. The efficacy to control blue and green mould on apples and oranges, respectively, of these packed and stored cells was similar to fresh CPA-2 cells.


CONCLUSIONS
This work showed a suitable packaging strategy for a freeze-dried formulation of the CPA-2, providing a good shelf life and efficacy against the major postharvest diseases of apples and citrus based on a plastic bottle stored at cold or frozen storage conditions.


CONCLUSIONS
The last phase of the commercial development process for biocontrol agents is presented in this work. A bacterium-based product that ensures the efficacy, stability and easy application of the antagonist to control postharvest fungal diseases on fruit was successfully obtained.
IRTA, XaRTA-Postharvest, Lleida, Catalonia, Spain.
R
R
Torres
C
C
Solsona
I
I
Viñas
J
J
Usall
P
P
Plaza
N
N
Teixidó
D061046:Biological Control Agents; D032084:Citrus sinensis / Q000382:microbiology; D018857:Food Packaging / Q000379:methods*; D061353:Food Storage / Q000379:methods*; D005612:Freeze Drying; D005638:Fruit / Q000382:microbiology*; D006801:Humans; D027845:Malus / Q000382:microbiology; D020636:Pantoea / Q000502:physiology*; D012034:Refrigeration
D061046:Biological Control Agents
apples; biological control; oranges; packaging conditions; pathogens; shelf life