Influence of cutting size and packaging materials on the quality of fresh-cut winter squash (var. Ajijimang)

Winter squash (var. Ajijimang) washed in 100 mg.L-1 chlorine water and cut into 4 and 8 parts was packed in different packaging materials, 35 μm micro-perforated P-Plus (MPP), 50 μm polyethylene (PE), 80 μm nylon/PE (Ny/PE), and 90 μm PE films separately. Fresh-cut samples were then stored at 10℃ for up to 17 days. The 35 μm MPP having a high oxygen transmission rate (OTR) has the most stable gas exchange ratio while the 80 μm Ny/PE was the most unstable. Firmness of the mesocarp remained acceptable until the end of storage regardless of the cutting size. Soluble solids content (SSC) remained stable and even slightly increased to a certain extent within 6 days. An increase in pH after 10-day storage suggested the activity of microorganisms within the packaging films. Strong off-odor was detected in samples packaged in 80 μm Ny/PE film after 13 days of storage. Mold was observed in all 1/4 cut samples on day 13 except the sample packaged with 80 μm Ny/PE film. However, no mold was found in all 1/8 cut samples except 35 μm MPP film on day 13. Severe mold invasion was apparent on the onset of the 17-day storage in 35 μm MPP film and 50 μm PE film. Samples cut into 8 parts and packed in 80 μm Ny/PE and 90 μm PE films had less mold incidence compared with other two packaging films. Fresh-cut winter squash packaged in 90 μm PE film maintained quality with shelf-life of 10 days at 10℃. Winter squash as fresh-cut commodity, with the right packaging material has the potential for longer period of storage in retail stores.

Effects of Carbon Dioxide Treatment and Modified Atmosphere Packaging on the Quality of Long Distance Transporting “Maehyang” Strawberry

This study was conducted to investigate the effects of carbon dioxide (CO2) and modified atmosphere (MA) packaging on the quality of strawberry during long distance transportation. “Maehyang” strawberries (Fragaria x ananassa Duch.) with red color on 70% of the fruit surface were harvested in Gyeongnam province, Korea. The samples were placed in gas-tight chamber with 30% CO2 concentration for 3 hours at 3°C. Strawberry samples were then packaged with modified atmosphere-modified humidity (MA/MH) packaging film. Samples treated with CO2 alone and combined CO2 with MA packaging were stored for one day at 1°C, transported for 10 days at 1°C, and distributed for 3 days at 4°C. Carbon dioxide alone or combination with MA packaging was effective in maintaining quality of “Maehyang” strawberries. Carbon dioxide treatment significantly increased firmness and reduced softening index and decay rate during 14 day transportation and distribution. Samples treated with CO2 + MA had higher overall score with low softening index and weight loss after 14 days of transportation and low temperature distribution compared to CO2 treatment only. The results indicated that a short term application of CO2 or combination treatment of CO2 and MA could be good postharvest handling for maintaining freshness of “Maehyang” strawberries during long distance vessel export.

Changes in Physicochemical and Sensory Qualities of “Goha” Strawberries Treated with Different Conditions of Carbon Dioxide

Harvested strawberry fruit is highly perishable because of its soft texture and microbial infestation during postharvest handling. The applications of carbon dioxide (CO2) gas on the quality parameters of strawberry harvested in winter season have shown better effects in several studies. However, very little information is available for the same in summer harvested strawberry. This study was aimed at finding an optimum concentration and duration of CO2 treatment in strawberry fruit var. “Goha” harvested in summer season to increase or maintain postharvest qualities. Fresh strawberries were treated with 15%, 30% and 50% CO2 for 1 or 3 h and then stored at 4?C for up to 13 days along with untreated control. Strawberry samples treated with 50% CO2 for 1 or 3 h and both 15% and 30% for 3 h had higher firmness than samples treated with both 15% and 30% for 1 h and control. In general, total soluble solids (TSS) slightly increased or maintained during storage in all samples except control. The values of pH slightly declined whereas titratable acidity showed opposite trends. However, there was no significant difference found among CO2 treated samples. Lightness (L*) of “Goha” samples with no CO2 treatment decreased gradually while it was almost maintained in CO2 treated strawberries. Strawberry samples treated with 15% CO2 for 3 h maintained better quality with higher scores of overall quality and visual texture until 9 days of storage. Samples treated with 15% CO2 for 3 h also received lower softening scores until 9 days of storage compared to other CO2 treated samples. These results showed that 15% CO2 for 3 h condition could be an effective postharvest treatment for maintaining quality of “Goha” strawberry.