Understanding the Distribution Damage of Chitosan-coated Strawberry (cv. Monterey) Packed in Corrugated Container Caused by Location on Pallet

Strawberry is a non-climacteric fruit and highly susceptible to water loss, softening, and fungal spoilage. Strawberry firmness is a very important quality criteria for consumers. However, strawberries soften easily during handling and transportation. Therefore, edible films and coatings are gaining popularity to meet consumer demands and prevent economic losses during transportation. One of the most commonly used edible film and coating for fresh produce is chitosan. It provides excellent film-forming properties and maintains postharvest quality of fruit and vegetables. Chitosan improves the textural quality of fruits and reduces the loss of firmness. This study was designed to compare the quality of coated and uncoated strawberry as related to the location (bottom, middle, and top) of the corrugated containers on the pallet after being subjected to International Safe Transit Association (ISTA) 3H procedure, which simulates an air-ride truck vibrations on a vibration table. Strawberries (cv. Monterey) were obtained from Apio Inc. (Guadalupe, CA) at commercial ripe stage. Strawberries were coated with 1%, 2%, and 3% chitosan solutions. Briefly, 10, 20, and 30 g of chitosan was dissolved in 1000 mL of water that contained acetic acid. Fruits were then air-dried at ambient temperature and placed in corrugated box. Corrugated boxes were 21 tiers high on pallets. Boxes at tiers 1, 11, and 21 were marked as bottom, middle, and top, respectively. Corrugated containers were then subjected to the ISTA 3H procedure. Following the procedure, firmness and weight loss of 10 strawberries for each group were measured. Uncoated and coated strawberries placed on the top of tier had lower firmness values than the samples placed on middle and bottom tiers. It is possible that transmitted vibration levels were higher on the top of the tier. Therefore, strawberries on the top were more damaged compared to other fruits. In addition, chitosan coatings maintained the firmness of strawberry better than the uncoated fruits on the same location of the pallet. Similar results were obtained for weight loss of samples. The weight loss of strawberries placed on the bottom and middle tiers were lower than the samples placed on top. Chitosan coatings were effective to control the weight loss of fruits compared with the uncoated ones. [M.S. Aday thanks the Scientific and Technological Research Council of Turkey (TUBITAK) BIDEP-2219 for postdoctorate support.]