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ARS Home » Pacific West Area » Parlier, California » San Joaquin Valley Agricultural Sciences Center » Commodity Protection and Quality Research » Research » Publications at this Location » Publication #397236
Research Project: Improved Systems-based Approaches that Maintain Commodity Quality and Control of Arthropod Pests Important to U.S. Agricultural Production, Trade and Quarantine

Location: Commodity Protection and Quality Research

Title: Managing postharvest storage issues in ‘Shiranui’ mandarin

Author
item Obenland, David - Dave
item ARPAIA, MARY LU - UNIVERSITY OF CALIFORNIA

Submitted to: HortTechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/2/2022
Publication Date: 1/19/2023
Citation: Obenland, D.M., Arpaia, M. 2023. Managing postharvest storage issues in ‘Shiranui’ mandarin. HortTechnology. 33(1):118-124. https://doi.org/10.21273/HORTTECH05133-22.
DOI: https://doi.org/10.21273/HORTTECH05133-22

Interpretive Summary: Shiranui’ is a mandarin that is highly treasured for its unique and delicious flavor and that obtains premium prices in the marketplace. Although flavorful ‘Shiranui’ can sometimes lose flavor quality during storage. Waxes are often applied to mandarins to help maintain quality during storage but could be involved in making ‘Shiranui’ more prone to flavor loss under some situations. In this study a storage wax (SW) or no wax was applied just after harvest and then followed by a pack wax (PW) or a SW after storage. The effect of different wax combinations, storage times and temperatures on general quality and flavor was examined. Results indicated that the initial wax was not an important factor but the use of SW instead of either PW as the final coating led to higher internal oxygen levels in the fruit and less loss in flavor quality. This effect became more pronounced with increased storage time and when the final week was at 20°C. In a subsequent test the concentration of the final SW was increased from 1% to 5% and greater to lessen weight loss. Higher concentrations of SW, however, led to increased flavor loss. Use of SW as the final wax prior to marketing the fruit offers a way to reduce the risk of flavor loss in ‘Shiranui’.

Technical Abstract: ‘Shiranui’ is a mandarin that is highly treasured for its unique and delicious flavor and that obtains premium prices in the marketplace. Although flavorful ‘Shiranui’ has a tendency to develop off-flavor during storage. In this study we examined the use of different storage wax and shipping wax combinations to determine if flavor in ‘Shiranui’ can be improved after storage by adjusting wax coating protocols. In the initial test either shipping wax (SW) or no wax (NW) were applied after harvest or after 3 or 7 weeks of storage, and all were followed by application of either a SW or one of two types of pack waxes (PW) and then held 1 week at either 7°C or 20°C. Results indicated that the initial wax was not an important factor but the use of SW instead of either PW as the final coating led to higher internal oxygen levels in the fruit and less off-flavor formation. This effect became more pronounced with increased storage time and when the final week was at 20°C. Greater weight loss accompanied the use of SW as the final coating. In a second test SW with higher soluble solids concentrations (5%, 10% and 15%) were evaluated to attempt to reduce weight loss but this led to greater development of off-flavor and loss in acceptability than were observed when using the SW with 1% solids in test 1. ‘Shiranui’ is highly prone to developing off-flavor in storage, but this may be at least partially mitigated by using a SW as the final wax due to the increase in gas permeability that is obtained.