Fruit Produce Facts English
Recommendations for Maintaining Postharvest Quality
Maturity & Quality
Flesh firmness is used as a maturity index as follows:
Other indices include corking of lenticels, pattern of starch content, and internal ethylene concentration.
Temperature & Controlled Atmosphere
-1 to 0°C (30 to 32°F); freezing temperatures are -1.5 to -2°C (29 to 28°F)
Rates of Respiration
To calculate heat production, multiply ml CO2/kg·hr by 440 to get Btu/ton/day or by 122 to get kcal/metric ton/day.
Rates of Ethylene Production
Low end for 'Anjou' and high end for 'Bosc' and 'Comice' pears.
Treating pears with 100 ppm ethylene for 1 to 2 days can substitute for cold storage [4 to 8 weeks at -1 to 0°C (30 to 32°F)] in enhancing ripening. Optimum conditions for ripening are 15-22°C (59-72°F; the higher the temperature the faster the ripening) and 90-95% relative humidity; CO2 should be kept below 1%.
Responses to Controlled Atmospheres (CA)
Optimum range: 1-2% O2 + 0-1% CO2
Physiological and Physical Disorders
Senescent scald. Dark-brown skin discoloration begins as small spots and develops into large areas of skin turning brown after long term storage; brown skin may slough off. Prompt cooling and maintenance of optimum fruit temperature minimize this disorder. Occurs when fruit become senescent.
Use of Materials
The UC Postharvest Technology Center grants users permission to download textual pages (including PDF files) from this World Wide Web site for personal use or to reproduce them for educational purposes, but credit lines and copyright notices within the pages must not be removed or modified.
Except for these specified uses, no part of the textual materials available on the UC Postharvest Technology Center Web site may be copied, downloaded, stored in a retrieval system, further transmitted or otherwise reproduced, stored, disseminated, transferred or used, in any form or by any means, except as permitted herein or with the University of California's prior written agreement. Request permission from UC Postharvest Technology Center. Distribution for commercial purposes is prohibited.
The information in this fact sheet represents our best understanding of the current state of knowledge at the time of the latest update, and does not represent an exhaustive review of all research results. Links to any of these UC Postharvest Technology Center pages are permitted, but no endorsement of the linking site or products mentioned in the linking page is intended or implied by such a link.
How to Cite
Author(s) names. Initial publication or update date (located at the top). Title. Link to the specific Produce Fact Sheet webpage (Accessed date)
Example: Cantwell, M. and T. Suslow. 2002. Lettuce, Crisphead: Recommendations for Maintaining Postharvest Quality.