Modified humidity clamshells to reduce moisture loss and extend storage life of small fruits

Authors: Bai, Jinhe; Baldwin, Elizabeth - Liz; TSANTILI, ELENI - Agricultural University Of Athens; Plotto, Anne; Sun, Xiuxiu; WANG, LIBIN - Nanjing Agricultural University; KAFKALETOU, MINA - Agricultural University Of Athens; WANG, ZHE - Chinese Academy Of Sciences; NARCISO, JAN - Former ARS Employee; ZHAO, WEI - Former ARS Employee; XU, SAI - Guangdong Academy Of Agricultural Sciences; SEAVERT, CLARK - Oregon State University; YANG, WEIQIANG - Oregon State University

Submitted to: Journal of Food Packaging and Shelf Life
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/31/2019
Publication Date: 8/20/2019
Citation: Bai, J., Baldwin, E.A., Tsantili, E., Plotto, A., Sun, X.N., Wang, L., Kafkaletou, M., Wang, Z., Narciso, J., Zhao, W., Xu, S., Seavert, C., Yang, W. 2019. Modified humidity clamshells to reduce moisture loss and extend storage life of small fruits. Journal of Food Packaging and Shelf Life. 22:100376. 10.1016/j.fpsl.2019.100376.
DOI: https://doi.org/10.1016/j.fpsl.2019.100376

Interpretive Summary: Small fruits, such as strawberries, blueberries, raspberries, cranberries, sweet cherries and table grapes comprise a fresh market industry valued at $10.9 billion in the U.S. alone for 2016. The estimated waste for fresh fruit is 28.7% - equaling a $3.1 billion food loss. A simple replace of the clamshell packaging can reduce the loss substantially, without increase of the cost. The new clamshell maintained lightly higher humidity in the packaging, and reduced the fruit weight loss by 2.6-fold. Fruit in the new clamshells had less quality deterioration and longer storage life.

Technical Abstract: Water loss is one of the major causes for the food loss and waste of small fruits, both in the retail market and at the consumer level. A modified humidity (MH) one-pound (~454 g) clamshell was designed for small fruit packaging and was compared to a typical commercial (COM) clamshell for several small fruits held in cold (0 -6 °C), refrigerated shelf (10 °C) and room (19 -25 °C) temperatures, typical in the industry for shipment, storage and marketing. Water loss of litchis, sweet cherries, strawberries, blueberries, Chinese bayberries, apricots, loquats and cherry tomatoes packaged in the COM clamshells was 1.2-4.5-fold more than for MH clamshells. Quality attributes of the packaged fruits were generally better maintained in the MH clamshells, especially for those attributes susceptible to water deficit, such as shriveling, desiccation-induced browning and/or drying of pedicels in cherries, calyx of strawberries, pericarp of litchis, peel shriveling of cherry tomatoes and softening of blueberries and strawberries. In the MH clamshells, relative humidity (RH) was often saturated with condensation on the top lid frequently observed, especially at low temperature and when transferring the clamshells from low temperature to room temperature. However, the MH clamshells did not induce a significant increase in decay by natural infection, except in one strawberry test and in inoculated blueberries that showed higher decay incidence in the MH clamshells than in the COM clamshells. The modification of the internal clamshell atmosphere (O2 and CO2) was minor to moderate (mostly less than 1 kPa change, with a maximum change of 3.6 kPa which is still minor for O2, but is probably not so for CO2). MH clamshells could be problematic in some cases because it is more prone to condensation especially when raising temperature from cold storage to room temperature during marketing. Overall, the MH clamshells substantively reduced water loss, maintained fresh fruit quality and extended storage life of small fruits without excessively modifying the package atmosphere and inducing decay.